| The double line ripple current and harmonics introduced by the double line pulsation power and the reactive power resulting from the transient unbalance power between the AC and the DC side will threat the safety, stability and reliability of the power converter operation. DC-Link capacitor is always been used for the power decoupling, eliminating the DC-Link harmonics. However, resulting from the lower reliability of the DC-Link cap which may generate a lot of heat for the flowing harmonics through the ESR, the DC-Link capacitor has gradually been the important puzzle which can not be ignore for the improvement of the power converter. What's more, active power decoupling method in single phase power converter for DC-Link cap free to improve the reliability of the converter arouses hot discussion between engineering and researchers.In this paper, the mechanism of production and the flowing path of the double line pulsation power and reactive power has been lucubrated through building the mathematical model of the single phase converter. Based on the differential single phase converter, the paper propose a novel active power decoupling method by controlling the waveform of the differential capacitors' voltages which can generate the double line pulsation power and reactive power for the AC side without any extra hardware, reducing the flowing path of the pulsation power and the cost, improving the efficiency and the reliability of the converter through decoupling at the AC side. Moreover, considering the cost and the efficiency of the converter, the paper optimizes the configuration of the differential caps through resetting the capacitance.Considering the single phase power converter without the differential feature, based on the waveform control method in differential converter for power decoupling, this paper propose a power decoupling modular by structuring differential cap structure from the topology as a modular and deriving the waveform of the capacitors' voltages which is contains only AC signals without DC bias voltage in modular. This modular can decouple the unbalance power without changing the formal converter structure and control strategies. Compared with waveform control method in differential converter, this control strategy can reduce the cycle current for improving the efficiency and make full use of the capacitance for lower cost.In the end, the simulation model and the prototype for differential single phase power converter and H bridge converter with power decoupling modular in Simulink have been build. The results of the simulation and the experiment validate the correctness and effectiveness of the proposed methods. |
PDF Full Text Request