Research Of Applying Hybrid Active Filter To Compensate Harmonics In DC-link Of The Inverter

As the rapid development of power electronics technique, Lots of power electronics devices have been applied in many fields. However, it also arouses the serious harmonic pollution in the power system. Now, harmonics of the power electronics inverter have been the most important resource in that of the power system. Passive components in power electronics system, especially electrolytic capacitor, not only have not obvious improvement in its size, cost and reliability, but also will decrease working life when it works in high temperature environment. In a word, the electrolytic capacitor becomes the feeblest part in the power system. To eliminate the disturbance of the harmonics effectively, Power electronics engineers have applied active power filters (APF) to substitute the electrolytic capacitor. But as a new device of harmonics compensation, APF has much shortcoming it couldn't overcome itself.Now, that APF associate with passive power filters (PPF) to compensate harmonics is the most effective method. With this method, system's capacity can be enlarged, cost can been decreased and performance can been improved. This paper apply shunt active-passive hybrid filter replacing the electrolytic capacitor to the dc-link of the inverter to realize the "silicon solution" of the electrolytic capacitor. Meanwhile the proposed scheme describe the new method that the hysteresis control system and the digital fuzzy logic control system is united to control whether the switch work or not. We apply MATLAB software to emulate the system. On this basis, we build the system based on the TMS320F240 chip so that we can improve the performance of the system by modifying software. The emulation and the experiment results verify the validity of the proposed scheme.