Development of active filter with compensation for unbalanced three-phase voltages

1. 产生了补偿三相不平衡电压的有源滤波器产生了补偿三相不平衡电压的有源滤波器。该系统主要由两个电路组成。一种是补偿电流谐波的有源滤波电路，另一种是补偿不平衡三相电压的电路。前一种电路与负载谐波电流合成反相电流，后一种电路与源电压负序电压合成反相电压。这些电路只有一个共同的能量存储电容器。因此，与其他单独使用有源滤波器和不平衡电压补偿器的系统相比，该系统对储能电容容量的要求较低。换句话说，我们可以使我们的有源过滤系统更紧凑。有源滤波电路的稳态分析一组19个同步差分cqu，导出了一个有源滤波电路的更多参数，并计算了电流的各种波形。分析结果与实验结果吻合。根据分析结果，设计了抑制有源滤波器PWM逆变器产生的谐波电流的无源滤波器。在分析结果的基础上，提出了一种双电流环有源滤波电路。采用双电流回路，既可以提高电流控制的响应，又可以提高系统的稳定性。补偿三相不平衡电压有源滤波器的稳态分析除第2节中的19个微分方程外。推导了新的13个不平衡电压补偿器的微分方程，并计算了电流和电压的各种波形。分析结果与实验结果吻合。分析结果和实验结果都表明，源电流的THD和三相电压的不平衡得到了改善。因此，指出了所提议的系统的可用性。少

1. Producing of active filter with compensation for unbalanced three-phase voltagesAn of active filter with compensation for unbalanced three-phase voltages was produced. This system mainly consists of two circuits. One is an active filter circuit to compensate for current harmonics and the other is a compensator for unbalanced three-phase voltages. The former circuit is operated to synthesize currents which are antiphase with the load harmonic currents and the latter is operated to synthesize voltages which are antiphase with the negative sequence voltages of the source voltages.Thses circuits have only one energy storage capacitor in common. Therefore, this system needs lower capacity of the energy storage capacitor in comparison with other system which an active filter and an unbalanced voltage compensator are operated independently. In other words, we can make our active filter system compact.2. Steady state analysis of active filter circuitA set of 19 simultaneous differential cqu … More ations for an active filter circuit was derived and various waveforms of currents were calculated. The analytic results coincided with the experimental. Next, a passive filter to suppress the harmonic current generated by the PWM inverter of the active filter was designed with the analytic results. On basis of the analytic results, an active filter circuit with double current loops was proposed. By using these double current loops, both response of current control and stability of the system can be improved.3. Steady state analysis of active filter with compensation for unbalanced three-phase voltagesIn addition to the 19 differential equations in the section 2. , new 13 differential equations for the unbalanced voltage compensator were derived and various waveforms of both currents and voltages were calculated. The analytic results coincided with the experimental. In both analytic and experimental results, improvement in THD for the source corrents and in unbalance of the three-phase voltages was shown. Consequently, the availability of the proposed system was indicated. Less