CONTROL SYSTEM AND METHOD FOR PHOTOVOLTAIC MEDIUM-VOLTAGE DISTRIBUTED CONTROL SYSTEM

摘要

A control system and method for a photovoltaic medium-voltage distributed control system. The photovoltaic medium-voltage distributed control system comprises N photovoltaic modules, N direct current-direct current converters (1), a direct current-alternating current converter (2), and an industrial frequency transformer (3), wherein output ends of the N direct current-direct current converters (1) are connected to a direct current bus in parallel; the direct current bus is connected to the direct current-alternating current converter (2); the industrial frequency transformer (3) is adapted to be connected to a medium-voltage alternating current power grid. The control system comprises a bus voltage sampling circuit and N direct current-direct current converter control circuits (4) in one-to-one correspondence with the N direct current-direct current converters (1), wherein each direct current-direct current converter control circuit (4) comprises a bus voltage sampling circuit, a photovoltaic sampling circuit, a droop controller, a maximum power point tracking controller, an input voltage loop regulator, and a pulse width modulation wave generation circuit. Communication is carried out by using a direct current bus voltage to replace a signal line, a communication system is greatly simplified, and reliability of the control system is improved.