请教xkw1cn版主关于IRS2092的问题，亦欢迎大家指导讨论。。

       使用IRS2092S D类功放做交流恒流源，功放输出接升流器，升流器次级所接负载阻抗很低，相当于短路。在功放无输入信号的情况下，发现在某些时候，供电电源电压会被抬升，测试功放中点输出方波也由原来
50%占空比变成小于50%的占空比，而在功放输入加信号后，电源电压恢复正常。
IR技术文档里也有这么一段描述偏压的话：
Since the IRAUDAMP9 is a half-bridge configuration, bus pumping does occur. Under normal
operation during the first half of the cycle, energy flows from one supply through the load and into
the other supply, thus causing a voltage imbalance by pumping up the bus voltage of the receiving
power supply. In the second half of the cycle, this condition is reversed, resulting in bus pumping
of the other supply.
The following conditions worsen bus pumping:
– Lower frequencies (bus-pumping duration is longer per half cycle)
– Higher power output voltage and/or lower load impedance (more energy transfers
between supplies)
– Smaller bus capacitors (the same energy will cause a larger voltage increase)

问题一：请问我这个电源电压偏压的情况正常么，有什么好的解决办法呢

问题二：在功放输出电流20A，而输出电压很小时，测得功放输出中点波形有较大的过冲（波形如下图），这个电压看起来已经超过IRFP4227的耐压，有炸管危险吧，该如何减小呢
空载时功放输出中点波形

功放输出20A时的中点波形