VEHICLE HEAT PUMP DEVICE AND ELECTRIC-POWER SEMICONDUCTOR OVERHEAT PROTECTION METHOD

摘要

PROBLEM TO BE SOLVED: To provide a vehicle heat pump device and an electric-power-semiconductor overheat protection method capable of both protecting the overheat of a drive circuit of a high-temperature-side water pump and maintaining an air conditioning capability in a case of using two types of cooling liquid as secondary refrigerant.SOLUTION: This vehicle heat pump device is configured to increase a rotational speed of a fan of a radiator radiating heat of first cooling liquid to an outside of a vehicle if a temperature of an electric-power semiconductor for supplying electric power to a first water pump that transports the first cooling liquid making heat exchange with high-temperature and high-pressure refrigerant exceeds a predetermined temperature during a cooling operation.