The Simulation And Research On Shunt Active Power Filter

As various power electronic products are widely used in many fields, especially those inverter with large capacity, the pollution from these nonlinear products to power grids are becoming more serious. And the requirements of modern life and industry on power quality are becoming more demanding. The problem of harmonic pollution has attracted much attention, so there come to being many kinds of equipments correspondingly to eliminate the harmonics. Compared with passive power filter (PF), active power filter (APF) has advantages in the performance of dynamic and passive power compensation, and so a better perspective.Referring to many related technology, as to the harmonic detection part in APF, p-q and ip-iq method based on the instantaneous reactive power theory was detailed, and an improved harmonic current detection method was proposed for three-phase three-wire system. The low pass filter in traditional ip-iq method was replaced by an average-value-algorithm within one sixth fundamental period in this method, which can reduce time delay and calculation time.A novel double hysteresis current control (DHCC) method based on the voltage space vector modulation (SVM) was used as current tracking method. It combines the advantages of both SVM technology and the hysteresis current control technology. The outer loop hysteresis can ensure fast dynamic response and precision. The optimal voltage space vector is introduced to the inner loop hysteresis to decrease the switching frequency, and the switching loss is decreased too. The utilization of the DC bus voltage was also improved. Meantime, The demand of the precision and real-time are guaranteed with all these efforts. Meanwhile a soft-start control method was used to suppress over-current and over-voltage effectively while APF was just started.The simulation model by MATLAB/Simulink realized the proposed approaches, and the simulation and experiment results do validate the feasibility and performance of the proposed approaches.At last, the hardware circuit and the software based on the DSP TMS320LF2407 were developed. The peripheral circuits were elaborated in this thesis.