| | | | | 怎么发现漏感尖锋好大啊!
MBR20200肖特基二极管,二极管坏了,你有没有算出你的次级电压是多少?
vds未超过mos耐压值,你不加吸收电路,能保证生产时一致? |
|
|
|
| | | | | 如果测试方法没有问题,这种波形肯定是不能接受的。
怀疑你的测试方法有问题,探头被干扰了,将地线夹子取下来,用示波器自带的弹簧做地线试下。
若找不到地线环,也可以用细铜丝缠在探头地上测试。 |
|
|
| | | | | | | 恩,我从2110驱动波形之后都是用面包板插的电路,干扰应该挺严重,您看看四楼我回复的波形可以吗? |
|
|
| | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | |
|
|
|
| | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | |
|
|
|
| | | | | | | | | | | 遇到了一个新问题,我的开环半桥整流滤波的输出电压变化范围很小,请问这是怎么回事?
似乎接上整个开环电路以后,占空比调整的范围变小了 |
|
|
| | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | ?是个神马节奏?你的输入是啥?输出啥范围?电路啥样的? |
|
|
|
| | | | | | | | | | | | | | | | | 面包板有时候就是坑爹的
布线神马的引起各种奇葩问题 |
|
|
| | | | | | | | | | | | | | | [size=14.166666030883789px]许工,有个问题一直网上没查到,对称半桥有办法做软技术吗? |
|
|
| | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | 正常了有啥不好?半桥有很多方法做软开关。LLC/非对称都是不错的。 |
|
|
| | | | | | | | | | | | | | | | | | | [size=14.166666030883789px]哈哈,说的也是,还是正常的好 |
|
|
| | | | | | | | | | | | | | | | | | | [size=14.166666030883789px]再提一问,这应该是一张实际电路图,请问红色圈出来的部分是做什么用的啊?方便的话能解释详细点吗,然后我好理解理解,谢谢啦
|
|
|
| | | | | | | | | | | | | | | | | | | 不好意思,我想再问的具体一些,mosfet旁边的两个5W的电阻是什么作用呢,不是电容旁边采用并联均压电阻吗?那四个稳压管是什么作用呢,稳定输入电压?mosfet的吸收点入RCD上面为什么又各串联了一个电阻呢? |
|
|
| | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | 这是突波吸收电路,用来吸收功率管过电压的。对于这个电路,如果电流峰值小于50A;就没有必要用这个。 |
|
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | 请问一下,为什么说半桥mos体二极管的反向恢复特性可以抑制变压器的尖峰呢? |
|
|
| | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | 二极管电压钳位的结果。 |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | [size=14.166666030883789px]看了您的回复想了一下,上管导通时候因为体二极管的原因,使得输入电压和变压器那一端的电压,被钳位在0.7V,请问这么理解正确吗 |
|
|
| | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | 是的;理论上是这样。 |
|
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 请问一下,我想在半桥两个mos旁边加RCD,可是网上查到的都是反激的分析,我这种应该怎么分析呢?特别是电阻应该取多少阻值,多大功率的呢?我的输入是110V,我想因为二极管的原因电容应该不能去太小,103够吗? |
|
|
| | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 是否如果mos出来的电压波形尖峰值不超过mos的耐压值就不用吸收呢?总工,我看过你那篇吸收电路仿真贴,我想吸收还是对效率影响很大吧,电阻相当热,我现在只做个100W试一下,最后要做到1000W,可能是需要吧。 |
|
|
| | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | 是否需要;一方面看电流,另一方面看结构。如果设计的好;380V系统;400A出力也用不上RCD吸收。 |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [size=14.166666030883789px]嗯嗯,明白 |
|
|
| | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | 关于过压与吸收问题。
过压值高;自然需要吸收,由过压导致的电磁噪音大;也是需要吸收的。所以;不是测电压就能判断是否需要吸收,它是多方面因素决定的。
电流;结构;器件种类及EMI、输出噪音等都是影响条件。 |
|
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 请问开关电源变压器吱吱响是什么原因呢?开环的半桥,当占空比调小就不响了。
我是直流稳压电源限流后输入的主功率,变压器响后一开始没事,后来能够输入的电压急剧下降。
是因为变压器磁饱和吗?那是否不能在闭环的时候做到这么大的占空比? |
|
|
| | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | 很可能是变压器磁密取的比较高且有些发热。建议观察一下。 |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [size=14.166666030883789px]如果电路正常运行,变压器的响声不会造成电路损坏是吗? |
|
|
| | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | 短时间内没问题。直觉变压器温升比较高,高温会导致磁芯饱和磁感应强度降低而饱和。如是我说,你会发现,通一会儿电后,最高可工作电压会下降。 |
|
|
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | |
|
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | 才露馅,原来驱动的是三极管。 |
|
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 工作频率不高!我这长用这类管子搞100KHz。频率高不是理由,多是旁边并了4007这类的捣蛋 |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 基极的加速二极管是4007,集电极-发射极反向并联二极管是FR157···我看到这类电动车充电器电路都是这样的··· |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
|
|
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 请教,半桥输出波形干扰严重,基本上出现的尖峰和开关频率相同。我用的是LC低通滤波电路,47u电感,电容用的是104+147U电容。还试过470U电容,并联两个470U电容,470u+470u+104,470u+470u+104+103等等一系列电容尝试。。。都没什么太多改善,请问如何是好? |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | 这种是典型的PCB不良或驱动策略错误问题,需要依原理及PCB找问题。 |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 嗯,许工,应该是pcb的问题,已经解决啦。之前变压器吱吱响的事情,确实如您所说,输入电压急剧降低,我用热成像仪大概温度有30多摄氏度,应该不是在不正常的范围吧?请问一般怎么解决呢?换磁芯? |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 不是不是,刚测了一下,五十多瓦,占空比百分之八十多 |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
|
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 您好,我之前那个变压器问题暂时还没解决,按boss要求先实现功能,我就先做了个五六十瓦的电源。我们之所以要做这个电源是因为输入是蓄电池供电,开关电源可以稳定降压,所以一般是输入电压变化比较大。我现在用直流电源做输入,调节直流电源以后负载输出电压变化很慢。请问一般用什么仪器测试闭环的响应,可以给反馈补偿参数调整做参考? |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
|
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [size=14.1666660308838px]许工,请问在哪能找到好的关于开关电源布局布线的资料呢?书或者文章都行。我的pcb感觉布的不大好,尖峰很大 |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 这是艰难的工作,我自己也没找到合适的书,全是一点点试出来的。 |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [size=14.1666660308838px]向您请教一个实际问题。我做反馈的时候,一开始发现输出分压之后几乎没有电压了,后来明白是阻抗问题,我就把分压电阻改小了,误差放大器的输入电阻改大了,确实分压了,但是现在同相端几乎没有电压(我用tl494的,应该是同相端接反馈电压吧),都被那10K电阻弄去了。请问我应该怎么修改呢?
|
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 不知是图画反了还是真这么接了。。。 |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [size=14.1666660308838px]总工,我真这么接了哎,494应该是误差放大器的输出值越大,芯片输出的占空比越小,所以我想应该接到“+”吧。嘿嘿 |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [size=14.1666660308838px]我发现一个问题,电源在某些占空比的时候变压器会响,新换的变压器占空比小的时候响大的时候反而不响,您有这方面的经验吗? |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 那我应该在设定占空比的时候把这些占空比避开就行了是吗? |
|
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [size=14.1666660308838px]哈,了解 |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 看到您2008年回答的一篇帖子。。。关于噪音的。。。好详细的经验 |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [size=14.0740737915039px]请问一下,航空电源反馈回路不能用光耦隔离(应该是光耦抗噪性不好,温漂也大)[size=14.0740737915039px],除了磁反馈的方式(方案负载,面积很大啊),还要别的反馈方式吗?最近想我的半桥直接输出和前面的地接一起得了,最大输出1000W,三十多安培电流,最后做出来的电路能用吗?会用哪些问题(我能想到的一个是超过安全电压36V,一个是前后地不隔离以后共模噪声对前面的控制波形和输出纹波有影响) |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 隔离运算放大器!那可是超现方案的极品哈! |
|
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [size=14.0740737915039px]请问总工,我自己绕的变压器,连接上信号发生器的正弦交流信号,用示波器测试发现幅值特别小,但是用变压器厂家寄过来的变压器就没问题。我什么地方弄错了呢? |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [size=14.0740737915039px]额额,我重绕 |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [size=14.0740737915039px]我又绕了一个,可能不是短路问题。。。
[size=14.0740737915039px]我在变压器其中一个接头焊接了一个4.7k的电阻输入就正常了,我觉得可能是信号发生器驱动能力不足,您觉得呢? |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 也是啊,而且打样的就不存在这个问题。还是我弄的不对,唉 |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 遇到两个情况:
一个是高端mos导通的时候,在低端驱动波形上耦合出一个大约5V的尖峰,好像导致了有点同时导通,有什么方法可以解决呢?
还有一个,我调驱动波形的占空比的时候,驱动波形占空比是变的,但是两个mos中间输出的电压占空比不变,一直是个同样的方波,就是直到低端驱动波形来的时候才会变低电平。不正常啊。。。
在家暂时不方波上波形,能帮我想想办法吗 |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [size=14.399999618530273px]我想请问一下,mos旁边的两个稳压二极管的作用,是当高电平来的时候稳压在18V+另一个稳压二极管的正向压降,低电平来的时候,提供一个-(3.3V+稳压二极管压降)吗?
另外,和mos管并联的那个后画上去的二极管起什么作用呢?是什么原理呢?一直没分析明白啊 |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 想请教您两个问题,我做的半桥电路无论是开环还是闭环输出电压都会有一定程度的下降。比如说我想稳在输出10V,但是经过一定时间后,闭环下降到了9.968V(是用电子负载直接显示出来的电压值),这是什么原因呢?
[size=14.0000009536743px]另一个是一个关于反馈原理的问题。是否反馈电压和基准电压本身就应该有一定的差值,我的思考是三种类型型的反馈电路本质还是一个电压放大电路,所以这个电压的差值就和低频的放大倍数有关了。我这样想正确吗?
|
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 还有一个问题是,我做的闭环,占空比确实随输入的改变而改变,但是输出仍然变化,这样做闭环不就没有意义了吗,是否闭环只是针对小信号的扰动有很好的调节作用? |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PWM能调节下;输出有变,可能有几种原因:
1)开环增益小。
2)基准漂移。
3)输出线阻抗太高。
4)PCB地线有交调干扰。
建议查一下或清楚描述一下你的系统,最好有PCB图。 |
|
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ?功率管上咋有电位器?建议两管面对面安装,保证桥臂连线最短。 |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 电位器是驱动电阻,怕波形不好,实测可以调一调。
明白,改成面对面的。
地线这么布可以吗? |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 你这是多圈电位器,寄生电感比较大且电阻线很细。建议换标贴的。 |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [size=14.0000009536743px]收到 |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 再有疑问,变压器次级振铃现象严重,应该是我没加RC,阻抗比较低的缘故吧,因为整流二极管和电感离变压器挺近的,应该不是寄生参数的影响吧。
[size=14.0000009536743px]如过整流二极管扛得住,这个振铃需要想办法弄掉吗,哪种效率高些? |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [size=14.0000009536743px]我能这样理解吗?对于硬开关的振铃,其实是能量区域稳定的过程,强行吸收会使效率降低,但是软开关是谐振,所以振铃对软开关是有影响的 |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [size=14.0000009536743px]嗯,谢谢,有些想法不知道对错,有许工确认,十分感谢 |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 加大功率后,驱动波形变成这个鸟样了。。。。这是我驱动引线太长的原因吗?我把驱动电阻换成24欧姆的,希望能把下管开通时候上管耦合出来的那个尖峰变小,也没有什么用。。。。
|
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 不好意思啊,蓝色那个下管波形震荡是因为我示波器探头的地线没接上。
但是下管开关的时候确实使得上管耦合出一个尖峰,形成直通了。。。。
|
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 下官下降沿在上管耦合出来的那个尖峰已经十几伏了。。。我怎么记得以前没这问题。。。是不是应该在驱动信号线的下面走个地线? |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 不要走地线。建议示波器探头和地线夹短一起后接到你的电源测试地,看看有没有毛刺。
|
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 许工,这个是两个MOS中间对地的波形,出现这种波形是不是我带载带的太轻了?我试了重载确实好不少,不知道怎么理解这种现象?
|
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xkw1cn- 积分:131455
- |
- 主题:37517
- |
- 帖子:55635
积分:131455 版主 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
|
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 哈哈,解决了,原来是控制芯片有问题,同相端的阻抗不正常,换个就好了 |
|
|
|
|