Abstract: A method for controlling an induction motor using an equivalent circuit model, the equivalent circuit having a real component and an imaginary component, is disclosed. The method instead of measuring a plurality of induction motor parameters, the real and the imaginary component of the induction motor impedance are calculated based on the measured phase currents and voltages. The invention calculates a first control function based on the real component of the induction motor impedance, and a second control function based on the imaginary component of the induction motor impedance, and adjusts the induction motor excitation frequency until the first control function is approximately equal to the second control function. After the excitation frequency is determined, the motor torque is calculated by taking the square of motor voltage in the d-q reference frame.

Abstract: An electric air conditioner sustain system is disclosed. The electric air conditioner sustain system includes a compressor, an engine and an electric motor. The engine and the electric motor selectively rotate the compressor. When the engine is rotating the compressor and the engine stops, the electric motor is synchronously activated to maintain continuous rotation of the compressor.

Abstract: A method for controlling a hybrid compressor system is disclosed. The hybrid compressor system includes a variable displacement hybrid compressor that is selectively driven by one of an engine and an electric motor to cool a passenger compartment of a vehicle. The method includes the steps of transmitting a demand signal to activate an electric motor drive mode of the hybrid compressor system, whereby the electric motor drives the hybrid compressor, transmitting a compressor displacement signal to the hybrid compressor to set a displacement of the compressor to a minimum level, waiting a predefined time period, activating the electric motor to drive the compressor, determining a suction pressure of a suction chamber of the hybrid compressor, determining whether the displacement of the hybrid compressor is sufficient based on the suction pressure determination, and changing the displacement of the compressor if the displacement is insufficient.

Abstract: A system for driving a compressor is disclosed. The system includes an internal combustion engine in communication with the compressor for selectively driving an input shaft of the compressor; an electric motor in communication with the compressor for selectively driving the compressor when the compressor is not being driven by the engine; and a gear assembly operatively connected to a motor output of the electric motor shaft for changing a rotational speed of the motor output shaft.

Abstract: A method for controlling an induction motor using an equivalent circuit model, the equivalent circuit having a real component and an imaginary component, is disclosed. The method instead of measuring a plurality of induction motor parameters, the real and the imaginary component of the induction motor impedance are calculated based on the measured phase currents and voltages. The invention calculates a first control function based on the real component of the induction motor impedance, and a second control function based on the imaginary component of the induction motor impedance, and adjusts the induction motor excitation frequency until the first control function is approximately equal to the second control function. After the excitation frequency is determined, the motor torque is calculated by taking the square of motor voltage in the d-q reference frame.

Abstract: A method for controlling a hybrid compressor system is disclosed. The hybrid compressor system includes a variable displacement hybrid compressor that is selectively driven by one of an engine and an electric motor to cool a passenger compartment of a vehicle. The method includes the steps of transmitting a demand signal to activate an electric motor drive mode of the hybrid compressor system, whereby the electric motor drives the hybrid compressor, transmitting a compressor displacement signal to the hybrid compressor to set a displacement of the compressor to a minimum level, waiting a predefined time period, activating the electric motor to drive the compressor, determining a suction pressure of a suction chamber of the hybrid compressor, determining whether the displacement of the hybrid compressor is sufficient based on the suction pressure determination, and changing the displacement of the compressor if the displacement is insufficient.

Abstract: A system for driving a compressor is disclosed. The system includes an internal combustion engine in communication with the compressor for selectively driving an input shaft of the compressor; an electric motor in communication with the compressor for selectively driving the compressor when the compressor is not being driven by the engine; and a gear assembly operatively connected to a motor output of the electric motor shaft for changing a rotational speed of the motor output shaft.

Abstract: A fuel cell power generation system is disclosed which includes a primary fuel cell stack for generating a first quantity of electric power, an auxiliary fuel cell stack for generating a second quantity of electric power, a fuel handling subsystem for feeding a fuel containing hydrogen to the primary fuel cell stack and the auxiliary fuel cell stack, an oxidant handling subsystem including a compressor for feeding an oxidant containing oxygen to the primary fuel cell stack, and a controller electrically connected to the primary fuel cell stack, the auxiliary fuel cell stack, the fuel handling subsystem and the oxidant handling subsystem for controlling operation of the fuel cell power generation system.

Abstract: A fuel cell power generation system is disclosed which includes a primary fuel cell stack for generating a first quantity of electric power, an auxiliary fuel cell stack for generating a second quantity of electric power, a fuel handling subsystem for feeding a fuel containing hydrogen to the primary fuel cell stack and the auxiliary fuel cell stack, an oxidant handling subsystem for feeding an oxidant containing oxygen to the primary fuel cell stack, and a controller electrically connected to the primary fuel cell stack, the auxiliary fuel cell stack, the fuel handling subsystem and the oxidant handling subsystem for controlling operation of the fuel cell power generation system.

Abstract: An electric air conditioner sustain system is disclosed. The electric air conditioner sustain system includes a compressor, an engine and an electric motor. The engine and the electric motor selectively rotate the compressor. When the engine is rotating the compressor and the engine stops, the electric motor is synchronously activated to maintain continuous rotation of the compressor.