Secondary ripple current suppression method for direct current micro-grid two-way energy storage converters

The invention discloses a secondary ripple current suppression method for direct current micro-grid two-way energy storage converters. The secondary ripple current suppression method mainly comprises three parts, namely a droop control, an outer loop PI control of introducing a capacitor voltage fed back by a band-pass filter and an inner loop P control of introducing an inductive current fed back by the band-pass filter, wherein the droop control obtains a direct current side reference voltage of an outer voltage loop; the outer voltage loop introduces the capacitor voltage feedback of the band-pass filter to enhance the secondary ripple suppression effect; and an inner current loop introduces the inductive current feedback of the band-pass filter to solve the problem of a low dynamic response speed caused by limitation on the cutoff frequency of the voltage of the outer loop in the conventional voltage and current double closed-loop control. According to the secondary ripple current suppression method, the deviation of output voltages between the energy storage converters is reduced; the parallel current equalizing effect is improved; the service lifetime of a power electronic device is prolonged; and the current stress and the conduction losses of a switching tube are reduced.