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| | YTDFWANGWEI- 积分:109861
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积分:109861 版主 | | | 还有他控制IC的1脚(相当于3842的 1脚)有一个与电感同样震荡频率的震荡波形,因此我认为是他的环路参数有问题。不知道对不对。 |
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| | xkw1cn- 积分:131377
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积分:131377 版主 | | | 懒的连图都不画;从数据表上扣个图就算完了?不知要蒙谁还是啥意思。 |
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| | | | | | | 不好意思啊 许工 我等下把所有的图给贴出来
抱歉啊。。。希望能给与指点 谢谢 |
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| | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | Rb1减到1K左右;且串个1N4148,CO/Cf加大到104左右,Rf短接;甩掉OP07;直接反馈试试。 |
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| | | | | YTDFWANGWEI- 积分:109861
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积分:109861 版主 | | | | | | 他的这个电路控制IC的地跟输出不是一个地,OP07甩不掉的。 |
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| | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | 甩不掉也要甩。OP07只有0.1M带宽,反映比PI还慢,不震就怪了 |
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| | | | | | | | | | | | | | | 或者我把开关频率减小到一定程度看看是否还有震荡,是不是也可以说明我的op07有问题呢??
因为现在是100K左右的一个震荡,如果op07的带宽是0.1M的话 那还真是它引起的震荡啊。。。 |
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| | | | | | | YTDFWANGWEI- 积分:109861
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积分:109861 版主 | | | | | | | | |
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| | | | | | | | | | | | | | | | | 但是从芯片手册看不出来这个带宽这么低的啊??
那难道真是这个带宽很低引起的我的那个100K的震荡吗 |
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| | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | 往下
IIIIIIII
IIIIIIII
IIIIIIII
IIIIIIII
IIIIIIII
IIIIIIIIIIIIIIIIII
IIIIIIIIIIII
IIIIII
II
LOOK!!!
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| | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | 100K 20dB都勉强啊! |
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| | | | | | | | | | | | | | | | | | | | | 天哪 那是我的运放选择的不行啊 那哟没有带宽高的运放呢?
还有就是我上面的PI您让我换成积分的原因是? |
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| | | | | | | | | | | | | | | | | | | 哦 那是我的新片手册不全。。。
那我估计就是因为运放的带宽引起的这个100K的震荡吧
那有没有带宽比较高的运放呢?? |
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| | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | |
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| | | | | | | | | | | | | | | | | | | | | | | 恩 就是现在板子上不大好换。。。唉
当时没选好。。。 |
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| | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | 对了 许工 我还有一个工程问题想请教
就是一般运放在用起来会加一个offset的电位器 这个您觉得在实际运用中关系大不大呢? |
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| | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | 除非你对精度有很高要求,否则;这东西只会增加故障率. |
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| | | | | | | | | | | | | | YTDFWANGWEI- 积分:109861
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积分:109861 版主 | | | | | | | | | | | | | | | 看很多好的电源,实际上很少用到电位器,都是通过不同阻值的电阻来分压。 |
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| | | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | | 遇到特别精密的地方,用激光调值。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 恩 了解了 呵呵 那就不用那些校正的电位器了 估计没什么影响的。。。 |
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| | | | | | | | | | | | | | | | YTDFWANGWEI- 积分:109861
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积分:109861 版主 | | | | | | | | | | | | | | | | | 许工又来了,估计论坛80%以上的人连激光调值都不知道是啥意思,更不用说用过了。 |
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| | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | | | | 我也是在厚模工厂见到的。 |
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| | | | | | | | | | | | | | | | | | YTDFWANGWEI- 积分:109861
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积分:109861 版主 | | | | | | | | | | | | | | | | | | | 我以为你不用电位器天天用激光调值的设备来调整输出呢。 |
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| | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | | | | | | |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 恩 都是经验之道啊。。。
还得象二位大哥多多学习啊。。。 |
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| | | | | | | | | | | | | | | | | | | | | | | 刚才去电子大楼买了几个TL081 换上去后减法器不正常工作
我正电源接10V 负电源接地 输入输出的范围都没超过十伏 不会是081是假的吧。。。 |
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| | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | 许工的表情好纠结啊 是有什么不对劲的地方吗??
我现在减法器的功能运放出问题了 难不成真是芯片的问题吗 |
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| | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 这个跟在板子上区别大吗?因为板子上现在减法出来的电压居然比和还要大。。。
搞不懂 就换了个运放啊 其他都没动着 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 是不是我的运放输出饱和了??减法后的输出比加法还要大。。。 |
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| | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | | | 这款运放不能用在信号接近电源电压的输入状况。虽然它可以单电源工作,可毕竟是款双电源运放。
仔细在面包板上测试能用的范围;判断IC是好是坏。 |
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| | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | | | | | 愿意的话;不防一试
这个IC,6V就可以正常工作了。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 我现在正电源接的是10V 负电源接的是地 按道理说是没问题的啊。。。
乱了乱了、、、 |
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| | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | 还是仔细测一下吧!看看是运放的问题还是信号的问题。
输入可以用电位器给直流信号。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 许工 我测试了好几遍 在081正电源接10V 负电源接地的情况下
op07可以做减法器没问题的前提下 081就是有问题
我有疑问是参数不匹配的问题,可是两款运放的差距不在这上面的吧
搞不懂是不是我的运放真的有问题啊
我还从一家芯片商那要了几片TI的样片081 原装的 这两天到 到时候比较一下
但总是很疑惑。。。没找到什么问题的。。。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 对了 许工 我还有一个工程的问题请教一下;
就是峰值电流模式控制的补偿参数设定问题:
一般是不是我先把斜坡补偿那边确定一下,比如让补偿的斜率大于我的电感电流下降的一半
然后我再把电压环的PI零点设定在接近我的输出电容和负载电阻所构成的极点处
这样您看问题大不?或者在工程上说您一般是怎么补偿的呢?很想请教。。。 |
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| | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | 换片子 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 恩 呵呵 我要的几片样片今天或者明天回到 到时候换掉 真悲剧 以后再也不去电子大楼买芯片了。。。
对了 许工 关于控制环路补偿设计的问题 不知您能提供点工程上的建议不?? |
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| | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 是啊 就是觉得有时候计算起来很麻烦 而且有时候也不见得多对那种
所以才想能不能请教一些实际调试峰值模式的经验呢??
大概说几点吧 嘿嘿 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | 在这种DCDC里,我只用平均或卢棒控制模式。
由于控制余度及精度受限;峰值模式在这里基本无用。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 对鲁棒控制没怎么系统学过。。。那峰值模式的芯片3842什么的 不是很常见的芯片么 怎么会调不稳呢?而且按理说一个Buck电路是很容易稳的啊。。。
现在反倒开始有一些疑惑了。。。
还有就是一般运放芯片手册里标的带宽 我能不能用到它的六分之一左右呢? |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 电流断续时;384X很容易稳。一旦连续;就发散了!
384X也是可以做平均值控制的。
运放可用带宽;基本上是单位增益/放大倍数/6 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 恩 不会这么难稳吧。。。疯了
很多人都是说只要斜率补偿大一些 差不多调调控制环是能稳的啊。。。
那你发散的意思是这种模式根本就很难调稳吗??没有办法可以很好解决这个问题的吗? |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 斜率补偿
但是;想稳流就没门了。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 许工的意思是只能稳压是吗??那稳流的话就真的没办法了吗?
我尽快还上TL081试试
要稳流的话应该如何做一下 或者没其他办法了么?? |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 我是用的UCC3813啊 有电流内环的啊 只不过是峰值电流模式的。。。
那您之前说的想稳流没门是针对峰值电流模式说的么?? |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 显然自控没学好,打屁屁! |
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但是许工 很多人也是用这个芯片去做电流模式控制的呀 你不能说大家的都不能稳定电流 我觉得是不是太绝对了点呢。。。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 哦
那咋办呢
明明一个电压环就可以稳压输出的 我非得用峰值电流模式的
那我用峰值模式的话应该是稳流效果不好吧 不能说电路一定不能工作吧
因为我的稳定要求不高 因为这个只是我的一级而已 后面还有一级电路
所以我用峰值电流模式的话只要正常工作就好了啊。。。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 就你现在用的这些东西;足够做平均电流内环;电压外环的系统了。
千万别浪费啊! |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 怎么讲呢?你是说我现在用的电路足够可以改成平均电流模式控制的是吗??许工能说的具体详细点吗??最近为这个电流震荡的问题折腾惨了。。。
还想具体听听许工的建议和见解啊。。。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 先自己想想。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 因为采回来的开关管的电流直接给的是芯片 而芯片就是采用峰值电流模式控制的
还能改成平均电流模式的吗?
还请许工明示啊。。。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 采回来电感电流 给芯片处理 一样是电流峰值模式的啊。。。
你之前说的发散的问题还是没法避免的吧。。。??? |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 就别再用峰值检测功能脚了,行不? |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 问题是不用那个脚的话芯片的工作是不大正常的啊 那个脚必须得由一个信号
我可以把斜率补偿的信号给他。。。
但问题是你的PWM产生芯片内部是跟这个脚相连的啊。。。
这样的话 你可以外面加个运放构成电流误差放大器 给定是你的1脚输出 但是你电流误差放大器的输处给谁呢? |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 终于有点象样的思路了。不着急,好好想通了就成了。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 我很着急啊。。。许工 很希望能得到你的进一步指点啊。。。
可是想通了还是实现不出来啊。。。
这样的话我下面都找不到下手的点了唉。。。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 你的意思是说3813可以稳流。。。不需要外接你说的电流内环的情况下。。。???
许工真是惜字如金啊。。。期待你的高见啊。。。
我现在因为头疼工作的事和自己的各种纠结 老是试验做得不好。。。老出问题
都快毕不了业了唉。。。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 是这样的许工 我在做一个500W的宽范围输入通信电源 36-75V输入 12V输出 要求效率和功率密度 我采用两级来做 第一级是变形的Buck 输入36-48时输出36-48 输入48-75V时输出48V 第二级是全桥LLC电路 把36-48V变为12V输出
总体电源构架是这样的 现在第二级调的还可以 第一级老是出现震荡解决不了 后来从你的帖子中了解到峰值电流模式可能就稳流不行
现在在想着怎么往下继续做的问题。。。因为板子已经出来了 暂时不想做太多的改动。。。
许工你的建议呢?? |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 这就好办了。反正你不用稳流。取消电流反馈就可以了。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 但是需要过流保护的啊。。。
而且只用电压环的话那我的电流检测端怎么处理比较好呢? |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 许工的意思是我只用一个环 然后我不用电流反馈了 只需要把我的斜率补偿电路的输出给我的电流检测端子就行是把?其实我的全桥LLC也是没过流保护的
因为芯片的缘故 我用全桥的话过流保护要加个采样电阻 暂时没做这个 损耗什么的都由 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 许工 我现在还是用着op07做查分采样 然后把电流采样电阻短接掉 斜率补偿电路依然存在 然后母线加到应该调压的时候就开始系统不稳定 我电压环采用把PI的零点放在LC谐振点的三分之一左右的地方去补偿的。。。
您看这样电路还有什么问题么 或者又是op07带宽不够的问题引起的我的系统不稳定震荡呢?? |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | OP07在这里弄出了很大的移相。建议加大PI时间。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 我的TI的样片到了 待会吃完饭回来试试
我想就是把电压环PI的零点放在LC谐振点的三分之一处左右 然后调一下
还有就是需不需要在PI之外加个滤波 也就是在芯片1 2脚之间再加个电容 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 许工 我换上TL081之后 减法器依然是不对 本来运放的输出是两个电压之差 现在的输出比和还要大 而换作op07就没有这个问题 所以我想是不是TL081的供电不应该这么供电呢??因为我现在是正电源十伏 负电源接地 是不是一定要双向电源供电啊 因为减法器的原理没问题 有没有超出其电压范围 没有理由啊 唯一的解释是tl081的供电不对了、、、???
还有如果继续用OP07 的话 我的PI时间常数应该加大到多少合适呢??因为我还要补偿我的输出滤波的谐振点的啊???您怎么看这个问题呢??
等着许工指点一下啊。。。拜托了 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | TL06/7/8X系列都有这样的问题。当信号接近电源电压时;输出是正饱和。昨天要你测;却死活不做,今天头大了吧
如果OP07可以用,那就换OP27吧。全兼容,就是速度快点,价格高点。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 是这样的许工 我的输入信号其实离正电源还有距离的 输入1V左右,而电源是十伏 也算不上接近吧 只是最后可能会接近十伏 一开始没接近时都正向饱和了唉。。。
可以 那我就买两个OP27 那个是好贵 先去整芯片了。。。
一会就可以试验了 这几天为运放的事头打死了 尽量晚上向许工回报战况 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1V还不近啊!看看数据表是咋说的
晚上听你的好消息! |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 许工
我快疯了 我换上op27之后输出仍然是饱和的 怎么只有op07不饱和呢???
那如果只能用OP07的话,我的系统该咋办呢?? |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 是啊 我也搞不懂是咋回事 运放都这么容易饱和的吗??
我现在已经把采样电阻短接了,然后3813的电流检测端子只接了斜率补偿的输出端啊 现在就是只考虑稳压了啊 因为之前我的电路也贴出来了 电压的采样是要用到运放的啊 因为是差分采样。。。
咋办啊???。。。真头疼。。。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 既然只电压反馈;就甩掉外运放,直接用3813的误差放大器吧! |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 不是啊 我的输出电压反馈回来需要先做一个电压差然后再给我的3813的误差放大器的啊 所以运放可能还甩不掉。。。
我之前贴出的电路图上可以看到这一点的 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 电流反馈都没了;还要差分干嘛。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 什么意思啊 没听明白呢???
我是说我的电压采样需要一个减法器,因为我的输出的两点电压跟输入的地都不是一个地啊,所以电压采样是需要一个减法器采样的啊
所以差分采样跟电流反馈没关系吧。。。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 那个电阻我板子上接的是0欧的啊。。。还要端接吗??
而且这个跟我的差分采样关系大吗? |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 这还要运放做差分吗?
直接用3813的误差放大器吧! |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 许工 我晚上还是用op07 然后采样电阻还是加上了 0.09欧
电流波形是有这么个震荡的:
黄色的是占空比波形 我在想占空比是在震荡的啊 那我能不能直接通过补偿环路来做到稳压呢??
因为我总觉得电流模式的话至少可以稳吧。。。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 许工还没来么??
我在等着许工的救援啊。。。。。。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | OP07都成延迟环节了,还把它忽略啊!
赶紧大家PI时间! |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 我不是把他忽略
是不知道应该怎么处理PI呢?是应该把PI的零点位置放在哪合适呢?
而且现在主要是换用081和op27之后的减法器输出老是饱和那一种,所以没办法还是用op07。。。
但是不知要怎么改啊。。。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 许工 我现在按照参数上去由一个四K左右的震荡 是因为我的低频增益不够吗?
那我运放的延迟环节应该怎么样加环节去补偿呢?? |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 许工你好
我这两天试了好几种思路:
1.使用op07,但是担心的是带宽不够,系统一直也存在一个震荡问题
2.期间试了好多种环路的补偿方式和参数 都效果不好 系统一直没有很好的稳住
3.试过将电流环去掉改成电压单环,依然没有很好的改善。。。
3.换上op27,因为op27的差模最大输入是0.7V,所以我把减法器的各个参数都改了一下,可是依然采样的结果不好
4.刚刚试了一下你给我的建议,把Rf短接,也就是电压环是一个积分环节 我的电容是105的,但是刚刚母线上到开始调节占空比的时候板子就炸了,两个开关管和驱动芯片都炸了(因为小示波器的电流探头不在,没看电流),还没分析出来原因。。。(我猜的一个是忘了吹风扇,过热,但是理论上很轻的载时管子应该不会很热吧。。。),没头绪了。。。
很感谢许工这几天陪我帮我分析问题,可是现在我真的是能想到的都试过了,效果依然不行,所以能否恳请帮忙分析一下电路的问题到底是出在哪了?? |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 即便震荡也不该立马炸啊!
建议先抛开震荡;将占空比固定去来;使后级电路吧! |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 许工又来麻烦你了 嘿
我现在改成电压模式控制了 这个占空比的调节是一定要靠前级来做的
现在由一个很尖锐的噪声,就是在占空比一开始调节的时候(其实后来没敢再继续家母线)
你觉得这个噪音一定是控制环的问题么?? |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 我现在第一级和第二级是分别调试的 所以的话跟第二级还没关系 还没有连调 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 比例反馈怎么去掉啊。。。我的拓扑已经是这样的了,输出电压反馈肯定要有差分的啊。。。
难道这样就不能稳么??
实在搞不懂了。。。Buck电路峰值电流模式控制占空比大于0.5的时候一定不能稳么?? |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 短路Rf |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 许工说的Rf是哪个电阻啊? 我图中的rf 是PI零点的那个电阻啊 短路不就只有一个积分环节了么? |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 而且确实之前试过短接Rf的时候炸了管子和驱动芯片。。。
原因没有找到。。。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 绕了一圈;又回来了。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 因为怎么着都稳不了 我想还是用峰值电流模式吧
想再试试
许工说的是电压模式补偿器用积分环节是吧??
那我还有没有其他的路可以走啊??许工指条路吧。。。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 对于电流连续模式;用平均电流法更现实一些。大家那么多年,都是这样用的。
再就用单周期控制模式,比较新;但也很稳定(其实;就是完全斜率补偿反馈 )。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 那所谓的单周期补偿是不是我直接把我的三极管补偿电路的输出给三脚,然后不需要电流反馈,然后去补偿电压环是这样吗?
那我这么做是不是可以呢? |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 单周期;是三环控制。最内是斜率;中间是电流;外环是电压。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 那不是越来越复杂了么
我现在可能来不及做 现在最关键的是先调稳。。。
不知什么好的路可以走呢??现在比较着急。。。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 还是建议单环做起。烧的关键不是控制。一般;自激是不会烧管的。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 许工的意思是先改成单环 然后电压环用一个积分环节是吧???
我试试 做一下。。。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 怎么就是稳不住呢?一调占空比就开始有尖锐的噪音了。。。
我用的是积分调节器了现在 把Rf短接了。。。
系统根本就不能稳啊。。。疯了、、、
我积分电容是105的 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 许工 我发现母线从五十几伏刚开始调占空比那会到接近六十伏左右的时候占空比不稳,而且还有比较低的噪音,然后从六十伏一直到75V占空比都可以稳住了。。。
我现在用的是电压单环。。。
我现在仍然是轻载1A的情况下,
你觉得我有没有必要变成峰值电流模式的,现在电压模式也应该算稳住了吧?
还没有上功率,轻载稳住的话再上功率应该问题不大吧。。。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 还不算稳!加大PI时间/加大电容试试。电源要在全状况下稳定。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 我现在的PI相串联的两个参数是51K电阻和105的电容,电容都1UF了啊
要继续加吗??会不会太大了点呢??
那一开始调节占空比不稳的原因我猜想:
我的电路从36-52V输入时,上管输出最大占空比,因为我的控制芯片后面还加了4451和驱动芯片,这之间的延时造成下管此时占空比为0,一开始调节的时候出现不稳定现象呢?
另外就是系统还不稳定?? |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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- 主题:37517
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- 帖子:55621
积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 老忘不了Rf!真服死你啦!
建议用IR2011驱动。 |
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许工批评的是。。。
你的意思是Rf短接是吗?
我试过的,在五十几伏到接近六十伏会有尖锐的噪音,105的电容,难道我应该换上更大的电容然后只用一个积分环节吗?
用2011不行的 我的驱动芯片需要单输入双输出的那种的,当时找了很久才找到这一款安森美的 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | IR2183/IR20124/IR20955
后头两个IC还带可编程保护。20955还有过载延时保护功能。
IXYS也有一堆对应型号。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 师弟;我可没打击你哦。谁让你提前不沟通啊!象王兆安老师/杨旭教授/斐老师。。。都是大家啊!
守这这些专家不问不闻,那就是你的错啦! |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 老板最近忙的很 每周只有小组会才见 。。。
其实还蛮丢脸的,有些问题其实应该理解的 问老板的话自己都讲不清楚 越问越乱的
恩 我继续调试了,希望可以搞定。。。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 不会/不理解没啥丢人的。很正常!你要都会了;就是老师啦
许多头绪是要自己慢慢理的,理清就成功了! |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 小弟是新手,理想是做个工程师,但现在太菜了,请问大侠,你所说的“面包板”是什么暗语呀?是什么东西来的 |
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| | | | | | | | | | | | | | | | YTDFWANGWEI- 积分:109861
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积分:109861 版主 | | | | | | | | | | | | | | | | | 理想不错,要学会利用网络,你去BAIDU或淘宝搜索一下自然就有直观的认识。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | 难道我的供电不对??081用10V的供电不可以吗??应该可以的吧。。。
是一定要15V吗?? 这个应该没关系吧? |
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| | | | | | | | | | | | | | xkw1cn- 积分:131377
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积分:131377 版主 | | | | | | | | | | | | | | | |
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| | | | | | | | | | | | | | | 这么说来确实是没注意过的问题,在电源设计的时候好多说系统带宽在1/4-1/5,有的说考虑芯片的带宽,要设置在1/6-1/10。这个请许工讲解一下,呵呵 或者说一般的PWM芯片带宽多大呢?谢谢了 |
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| | | | | | | | | | | Co/Cf 加大到104,Rf短接 是说我只用一个积分环节是吗?可是我的op07甩不掉啊 因为输出是差分采样的啊...?直接反馈的话可能是有问题的?
或者有没有跟op07 pin to pin的运放,带宽可以高的 我可以用的那种试试的呢?? |
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| | | | | | | | | | | 我是做了一个差分采样啊。。。
一个减法器啊。。。应该不需要把。。。 |
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| | | | | | | 仍然由一个96K左右的震荡。。。
是不是我的环路补偿参数有问题呢??
还请许工指点啊。。。
图您能看得清楚吗??
或者您方便的话把QQ给我吧
我的是 362884550 |
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| | | | | | | 电路实际是一个Buck的变形结构:(采样用了一个减法器 差分采样) 电感和电容参数以我上面帖子中的为主 |
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| | | | | | | 驱动是有一个左右的震荡的。。。之前看过的 振荡频率的话不好判断。。。
那你的想法是? |
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