Active Frequency Support Control of Energy Storage Power Station Based on Photovoltaic and Energy-storage Microgrid

When the photovoltaic and energy-storage microgrid(PV-ESM) operate under a conventional droop or virtual synchronous generator(VSG) control, the system frequency will be unstable if the load is disturbed violently. To solve the problem, the feedback loop control strategy of the ESPS with a first order differential control links of high-pass filter is proposed from the aspect of optimizing energy storage power station(ESPS) dynamic power response, and the adaptive selection basis of damping coefficient and inertia time constant is given. An improved VSG frequency adjustment strategy based on feedforward power is proposed in order to support power frequency actively by EPSP power adjustment. Taking a typical off-grid PV-ESM scenario in an industrial park as an example, the simulation results show that the proposed strategy could support frequency recovery rapidly when frequency instability induced by load mutation and ensure the quality of power supply.