Multi-channel grid-connected power generation system and control method therefor

A control method for a multi-channel grid-connected power generation system, wherein in the multi-channel grid-connected power generation system, multi-channel energy conversion devices are connected in parallel, each of the multi-channel energy conversion devices is connected to a same collector line through a corresponding step-up transformer, one end of the collector line is connected to a power grid through one switching device, and the switching device is controlled to be switched on or switched off by one control unit;

• the control method comprises:
• sending, by the control unit, a switch-off command to the switching device in a case that the control unit determines that each of the multi-channel energy conversion devices is in a non-operational state;
• and
• in a switch-off state of the switching device:
• starting at least one energy conversion device to operate as a voltage source to establish an alternating current (AC) voltage in a case that a start-up condition is met, so that a phase difference and an amplitude difference of a voltage across the switching device are both stabilized within an allowable error range;
• sending, by the control unit, a switch-on command to the switching device;
• and
• starting other energy conversion devices in the multi-channel energy conversion devices other than the at least one energy conversion device to operate as a current source to transfer energy to the power grid;
• wherein meeting the start-up condition indicates that an energy value of a front-stage power supply of an energy conversion device is not lower than a preset value required by said energy conversion device and said energy conversion device is not prohibited by a centralized control room, and the other energy conversion devices include energy conversion devices of which a corresponding start-up condition is met.