초록 ▼

An electronic motor drive for vector control of an induction motor controls slip and operating frequency in response to changes in stator voltage. The drive includes a torque control loop, a flux control loop and a frequency control loop which includes slip control in response to a voltage differenc

An electronic motor drive for vector control of an induction motor controls slip and operating frequency in response to changes in stator voltage. The drive includes a torque control loop, a flux control loop and a frequency control loop which includes slip control in response to a voltage difference. In the constant horsepower range, above base speed, slip is controlled in response to an error between a d-axis reference voltage that is sampled at base speed and a d-axis feedback voltage that is sensed when the motor is operating above base speeed. Flux-weakening is provided in response to an error between a q-axis reference voltage that is sensed when the motor is operating at base speed and a q-axis feedback voltage that is sensed when the motor is operating above speed.

대표청구항 ▼

A method for controlling slip in an induction motor having a stator and rotor, the method comprising: controlling stator voltage in response to a difference between commanded stator current and actual stator current, and in response to a stator operating frequency command; determining a rotor freque

A method for controlling slip in an induction motor having a stator and rotor, the method comprising: controlling stator voltage in response to a difference between commanded stator current and actual stator current, and in response to a stator operating frequency command; determining a rotor frequency that is responsive to the rotational speed of the rotor; determining the stator operating frequency command from the rotor frequency and a slip frequency command; generating a stator voltage command in response to a preset parameter; determining voltage feedback representative of actual stator voltage; determining a voltage error as a difference between the stator voltage command and the voltage feedback representative of actual stator voltage; applying a control function to the voltage error to generate a slip multiplier for torque-producing current; multiplying the slip multiplier by a command for torque-producing current to control the slip frequency command; changing the slip multiplier in response to the voltage error to control the slip frequency command; and algebraically summing the slip frequency command and the rotor frequency to control the stator operating frequency command.