Energy-saving control method of asynchronous motor

Abstract

The invention discloses an energy-saving control method of an asynchronous motor. The method comprises the following steps: supplying power to the asynchronous motor through an inverter, and controlling the asynchronous motor through a rotating speed regulator, wherein the inverter comprises a power module and a control module which is provided with a digital signal processor (DSP); sending the difference between a given motor angular speed omega<*> and a measured actual motor angular speed omega into the rotating speed regulator, wherein the output quantity of the rotating speed regulator is a given electromagnetic torque Te<*> of a motor, and omega s<*> represents an optimum slip angle frequency under which the asynchronous motor operates; performing calculation according to the given electromagnetic torque Te<*> and the optimum slip angle frequency omega s<*> to obtain a torque current component Isq of the motor under a two-phase rotating coordinate system; performing calculation according to the torque current component Isq and the optimum slip angle frequency omega s<*> to obtain an exciting current component Isd of the asynchronous motor; performing calculation according to the torque current component Isq and the exciting current component Isd of stator current to respectively obtain stator two-phase voltages Usd and Usq under a steady operation state; performing ipark operation to obtain two-phase voltage components Us alpha and Us beta of the asynchronous motor under a two-phase static coordinate system, and further controlling the inverter through space vector pulse width modulation so as to realize the energy-saving control on the asynchronous motor.

Description

technical field [0001] The invention relates to motor control technology, in particular to an energy-saving control method for an asynchronous motor. Background technique [0002] Asynchronous motors are the most widely used in various motors due to their simple structure and high reliability. Since the 1980s, their frequency conversion speed control systems have gradually gained popularity, and their energy-saving effect is remarkable in the speed control drives of fans and pumps. . [0003] When the asynchronous motor powered by the inverter is running in a non-rated state, the efficiency is often lower than the rated operation, especially in the low-speed and light-load state, and the motor in actual operation often works in a light-load state, which is the so-called " This is an old problem encountered when the motor is running, and the motor also encounters this problem after frequency conversion and speed regulation, especially when the fan and water pumps account for...

AI Technical Summary

Problems solved by technology

However, when the asynchronous motor is running, the core loss accounts for about 20%-40% of the total loss of the motor. Therefore, the energy-saving control method that ignores the core loss will inevitably have a greatly reduced energy-saving effect.

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