Study on Cooperative Control Strategy of Back-to-Back Dual-PWM Converter based on power Feedforward

摘要

In traditional back-to-back dual-PWM converter system, DC-bus voltage is affected by load and grid impact of fluctuations, threating the safe operation of the system. In order to reduce the DC voltage fluctuation, a power feedforward control strategy was proposed according to the instantaneous active power balance. In this strategy, the load active power was directly fed-forward to the grid-side given instantaneous active power node through a constructed load state feedforward channel, which avoided the slower process of indirect power adjustment through outer voltage loop. So, the system response speed was greatly accelerated, the DC-bus voltage fluctuation was inhibited effectively, and the dynamic performance of the system had improved. Simulation results demonstrate the effectiveness of the proposed strategy.