Motor speed control device and household appliances

Abstract

The present invention discloses a motor speed regulation device and a household electric appliance. The motor speed regulation device comprises: a first switch module connected in parallel with a motor, the first switch module consisting of a first charging module, a first diode, a first voltage stabilization module and a first switch tube which are connected in series; a second switch module connected in series with the motor, the second switch module consisting of a second charging module, a second diode, a second voltage stabilization module and a second switch tube which are connected in series; a first driver configured to drive the first switch module; a second driver configured to drive the second switch module; and a control module configured to control the first driver through a first PWM signal and control the second driver through a second PWM signal, the first PWM signal and the second PWM signal are subjected to mutual self locking. The motor speed regulation device of the embodiment of the invention is able to improve the reliability of controlling speed regulation and simplify the direct current power supply circuit in a motor speed regulation circuit, so that the cost is reduced and the corresponding package size is decreased.

Description

technical field [0001] The invention relates to the field of motor control, in particular to a motor speed regulating device and a household appliance. Background technique [0002] related technologies, such as figure 1 As shown, it is modulated by "single-phase AC switching circuit" PWM (Pulse WidthModulation, pulse width modulation). Specifically, the voltage at both ends of the motor is turned on and off at high speed, so as to adjust the average voltage at both ends of the motor to achieve the purpose of speed regulation. When the "motor inductive current discharge circuit" is a switch circuit, figure 1 can be simplified to figure 2 . Such as figure 2 As shown, the switching dead time between K1 and K2 (ie: the time from K1 off to K2 on and the time from K2 off to K1 on) is controlled according to the voltage generated when K2 switches, and the dead time is uncontrollable. And it is greatly affected by the difference in time characteristics of K1 and K2 devices,...

AI Technical Summary

Problems solved by technology

like figure 2 As shown, the switching dead time between K1 and K2 (ie: the time from K1 off to K2 on and the time from K2 off to K1 on) is controlled according to the voltage generated when K2 switches, and the dead time is uncontrollable. And it is greatly affected by the difference in time characteristics of K1 and K2 devices, which may cause temporary short circuit of K1 and K2, resulting in temperature rise of K1 and K2, or even burning; and it needs a separate DC power supply circuit, which is costly and expensive. Complex, it is difficult to miniaturize the packaging volume

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