PV POWER CONVERTER AND CONTROL METHOD AND PV POWER PLANT USING THE SAME

摘要

A PV power converter (4a, 4b, 4c, 4d), its control method and a PV power plant, the PV power converter includes: output terminals, input terminals being configured to be electrically coupled to output ends of PV array (2a, 2b, 2c, 2d), a power conversion circuit being configured to convert power supplied from the PV array (2a, 2b, 2c, 2d), and output the converted power at the output terminals, having at least one power switch being electrically inserted between the input terminals for bypassing a flow of the converted power around the output terminals, and a local controller (9a, 9b, 9c, 9d) being configured to close the power switch in response to an occurrence of a fault external to the PV power converter (4a, 4b, 4c, 4d) and keep the power switch closed for a predetermined time interval longer than a switching period of the power conversion circuit. This is helpful for decreasing the DC short circuit value while not relying on the conventional fault clear devices, such like fuses and circuit breaker. Consequently, this makes the system cheaper by not using the sorts of fault protection devices.