The novel digital control restraining circulating currents strategy based on tracing the transient average current in parallel inverter system

The conventional method by power regulation to restrain the circulating current is affected by the parallel impedance and has other disadvantages in the response speed and harmonic component of circulating current, etc. The strategy to restrain circulating current based on tracing transient average current feedback was proposed in the paper by the combination of tracing transient average current feedback control and power regulation strategy. The mathematical model of the strategy based on tracing the transient average current was analyzed. It is discussed that is the characteristic of the power regulation after introducing to tracing the transient average current and new digital simplified power detection technique in the parallel inverter system. The relevant experiments on the novel strategy by the combination of tracing transient average current were verified the better characteristic of restraining the circulating current by the results of the experiment in two-parallel-inverter system.