Cooling system of electric automobile and electric motor used therefor

A cooling system for an electric vehicle, comprising

• an electric motor for producing driving force,
• a controller for controlling said electric motor,
• a battery,
• a main cooling circuit including a pump and a radiator for forcibly recirculating coolant by said pump through said controller, said electric motor and said radiator to cool said controller and said electric motor, wherein said controller and said electric motor forms a heat source:
• a battery heat retaining circuit fluidly connectable to said main cooling circuit between said heat source and said radiator such that the coolant having passed through said heat source flows to heat said battery;
• a by-pass circuit fluidly connectable to said main cooling circuit such that the coolant bypasses said radiator;
• and
• means for selectively effecting connection or disconnection between said main cooling circuit and at least one of said battery heat retaining circuit and said bypass circuit according to outside temperature;
• wherein means is provided for changing an operation of said pump to recirculate the coolant at a predetermined minimum flow rate when the coolant, which has passed through said electric motor and said controller and is raised in temperature, is passed through said battery heat retaining circuit to heat said battery.