基于DSP的三相四线制有源滤波器的研究

Study based on three-phase four-leg APF of FBD method

针对配电网三相四线制系统的谐波、零线抑制以及有源电力滤波器补偿的实时性问题,提出了双DSP控制的三相四桥臂有源电力滤波器方案。主电路采用三相四桥臂结构的逆变器,由其产生的补偿电流与负载的有害电流分量大小相等,方向相反,从而使经该滤波器补偿后,电源电流的谐波和零线电流得到很好的抑制。数字控制方面主要由两片TMS320F2812DSP芯片完成。一片DSP主要负责信号数据采集;另一片DSP主要负责指令电流的运算。这样可以大大提高系统的运行速度,保证了有源电力滤波器补偿的实时性。本文介绍了三相四桥臂有源电力滤波器的数学模型、工作原理、检测和控制方式,并对系统的硬件构成和软件主程序流程作了阐述。通过MATLAB软件仿真验证了此方案的可行性。

A three-phase four-leg active power filter controlled by dual-DSP program was proposed for the problem of harmonicsi ￠neutral current suppression in the three-phase four-wire system of distribution network and real-time on active power filter compensation. Three-phase four-leg inverter was applied as the main circuit structure and it can generate the compensation current which has the same size and the opposite direction of the harmful current component from the load. So that the supply current harmonics and the zero line current were well inhibited. The digital control task was mainly executed by the two TMS320F2812 DSP chip. One piece of DSP is mainly responsible for the collection of the signal data. The other one is mainly responsible for the command current operation. This can greatly improve the system speed and guarantee the real-time compensation of the active power filter. The mathematical model、 works、 detection and control methods of the three-phase four-lag active power filter were described in the paper, the hardware structure and the main program flow of software was elaborated at the same time. Simulation and experimental results verified the feasibility of the system.