Cooling system for hybrid power system

A cooling system comprising:

• an engine;
• an engine cooling circuit to deliver coolant to the engine, the engine cooling circuit including a radiator and a main fan to draw air through the radiator of the engine cooling circuit;
• an inverter;
• an inverter cooling circuit to deliver coolant to the inverter, the inverter cooling circuit including a coolant pump operatively coupled to a heat exchanger, the coolant pump to drive coolant though the inverter cooling circuit, the heat exchanger located such that the main fan draws air through the heat exchanger when the main fan is active;
• a secondary fan to selectively draw air through the heat exchanger of the inverter cooling circuit;
• a controller configured to control operation of the secondary fan;
• the main fan and optionally the secondary fan being configured to draw cooling air across the heat exchanger of the inverter cooling circuit during modes when the engine is running, and the controller being configured to operate the secondary fan to selectively draw air through the heat exchanger of the inverter cooling circuit during modes when the engine is not running, and
• the controller being configured to turn the secondary fan of the inverter cooling circuit on whenever the coolant pump is active.