Analysis of the Crossover Distortion Problem of Current Waveform

Through analysis, the fundamental reason for the distortion of the two-way total current waveform is that the frequency of the DC module I used is inconsistent, which causes the waveforms of the two currents on the bus to be out of sync in timing, resulting in incomplete superposition of the two waveforms. In this way, attenuation occurs at the intersection of the two currents, causing waveform distortion. However, the waveforms at the overlapped parts are normal.

 

As shown above, when testing the single-channel current waveform, the waveform is normal. Therefore, it can be determined that the distortion on the bus does not affect the stability and EMI of the power system. In this process, the inductive impedance caused by the inductance of the multi-core wire used in the large current and long transmission process was considered. After switching to a single-core copper wire for testing, it was found that the current and voltage ripple performance was better, but there was no improvement effect on the current crossover phenomenon.

 

The conclusion is that the waveform distortion of the bus current has little effect on the LED and the entire power system. Of course, if it is possible to consider the situation, the frequency of each module should be kept consistent to achieve timing synchronization. But in fact, due to the discreteness of each component in the process, it is impossible to achieve consistency. Therefore, maintaining consistency under the premise of controllability will be better for product quality.