Abstract: The invention relates to an electrical subsystem to power a vehicle refrigeration system. The electrical subsystem includes an AC drive electrically coupled to a high voltage DC bus. The AC drive provides “refrigeration compressor AC power” responsive to a cooling demand. The electrical subsystem also includes a “low voltage DC bus”. The low voltage DC bus powers a plurality of low voltage refrigeration components including refrigeration fans. A microcontroller sets the compressor AC voltage and the compressor AC frequency. A method of preventing vehicle refrigeration system compressor stall includes the step of limiting the electrical AC power to the compressor such that the AC voltage does not droop causing a compressor stall. Also, an electrical subsystem for powering a compressor in a vehicle refrigeration system includes “V/f” operating information for the compressor, and a microcontroller commands the AC voltage and the AC frequency to the compressor.

Abstract: A refrigerant system is provided where the functions of an economizer heat exchanger and liquid-suction heat exchanger are combined. The two configurations are disclosed with a single common heat exchanger construction. In a first configuration, a series of valves selectively routes only one of two possible refrigerant flows through a common heat exchanger such that a control can selectively activate either an economizer heat exchanger circuit or a liquid-suction heat exchanger function. In a second configuration, both refrigerant flows are passed to the common heat exchanger through separate fluid lines and are selectively activated by the control. Variations of the second configuration are also disclosed.

Abstract: A refrigerant system is provided where the functions of an economizer heat exchanger and liquid-suction heat exchanger are combined. The two configurations are disclosed with a single common heat exchanger construction. In a first configuration, a series of valves selectively routes only one of two possible refrigerant flows through a common heat exchanger such that a control can selectively activate either an economizer heat exchanger circuit or a liquid-suction heat exchanger function. In a second configuration, both refrigerant flows are passed to the common heat exchanger through separate fluid lines and are selectively activated by the control. Variations of the second configuration are also disclosed.