基于柔性励磁功率控制的载波同步策略

Carrier Synchronization Strategy Based on Flexible Excitation Power Control

基于绝缘栅双极型晶体管(IGBT)电力电子元件的柔性励磁功率控制系统响应速度快,满足现今发电机大电感励磁回路的场合,但因功率回路并联引发的环流问题会导致输出电流畸变,增加系统损耗甚至造成系统崩溃。为此提出一种柔性载波同步策略抑制并联型功率控制器的环流问题。在功率控制并联模型的基础上,设置一个同步信号输出单元和若干个并联的功率控制器模块。同步信号输出单元向功率控制器模块内部的模拟载波发生器发出同步脉冲信号,模拟载波发生器同步清零,产生从零开始的锯齿波信号;实际载波发生器与模拟载波发生器同步清零,产生从零开始的三角波信号;通过模拟载波发生器的同步达到实际载波发生器的同步。此外,上述方法无需增加额外的硬件,提高了系统效率。实验验证了载波同步方法能够在不同功率点下实现很好的环流抑制效果,同时输出电流波形质量得到很大改善。

The flexible excitation power control system based on insulated gate bipolar transistor(IGBT)power electronic components has a fast response speed and meets the requirements of today’s generator large-inductance excitation circuit.However,the circulation current problem caused by the parallel connection of power circuits may cause output current distortion,increase system loss and even cause system collapse.To this end,a flexible carrier synchronization strategy to suppress the circulating current problem of parallel power controllers is proposed.Based on the power control parallel model,a synchronous signal output unit and several parallel power controller modules are set up.The synchronization signal output unit sends a synchronization pulse signal to the analog carrier generator inside the power controller module,and the analog carrier generator is synchronously cleared to generate a sawtooth signal starting from zero,the actual carrier generator is synchronized with the analog carrier generator,and is cleared.A triangular wave signal from zero is generated,synchronization of the actual carrier generator is achieved by synchronization of the analog carrier generator.In addition,the above method does not require additional hardware to improve system efficiency.The experiment verifies that the carrier synchronization method can achieve good loop suppression effect at different power points,and the output current waveform quality is greatly improved.