System and method for connection of photovoltaic arrays in series and parallel arrangements

A photovoltaic (PV) power system comprising:

• a plurality of PV arrays each configured to generate a direct current (DC) output from received solar irradiation;
• a PV inverter electrically coupled to the plurality of PV arrays to receive the DC output therefrom and invert the DC output to an AC output usable by a load connected to the PV inverter, the PV inverter including a DC link that operates at a variable DC link voltage that is determined by the PV inverter according to a global maximum power point tracking (MPPT) algorithm;
• a contactor arrangement positioned between the plurality of PV arrays and the PV power inverter and including a plurality of contactors that are switchable between an on state and an off state to selectively connect the plurality of PV arrays to the DC link and so as to control a level of DC voltage received by the PV inverter from the plurality of PV arrays;
• a controller in operable connection with the contactor arrangement, the controller being programmed to control operation of the contactor arrangement so as to cause the DC output provided from the plurality of PV arrays to the PV inverter to exceed a minimum PV inverter operation voltage value;
• and
• an arrangement of secondary contactors and resistors configured to load the plurality of PV arrays when the plurality of contactors are switched between the on state and the off state, so as to reduce a level of voltage on the DC link;
• wherein the controller is further configured to switch the secondary contactors when the plurality of contactors are switched between the on state and the off state to reduce the level of voltage on the DC link.