A switching device for motor wide speed

Abstract

The invention discloses a switching apparatus for a motor wide speed. The switching apparatus comprises a dynamic power supply module, a serial-parallel switching module and a PWM modulation and power driving module, wherein the serial-parallel switching module comprises N switching units, each switching unit comprises a first diverter switch, a second diverter switch and a third diverter switch, and the PWM modulation and power driving module is connected with the dynamic power supply module and the serial-parallel switching module. According to the invention, what is needed is only one independent dynamic power supply, the structure is simple, the cost is quite low, and the diverter switches are not damaged. Through controlling switching-on and switching-off of the diverter switches in the serial-parallel switching module, multiple serial-parallel states can be realized. Under the condition of quite a lot of motor windings in particular, the high-efficient rotating speed area of a motor can be enlarged by times, and the performance of the motor is greatly improved.

Description

technical field [0001] The invention relates to the field of motors and their controls, in particular to a switching device for wide-speed motors. Background technique [0002] As we all know, the maximum efficiency speed range of the motor has a range. When it exceeds this range, the efficiency of the motor will drop sharply. In most cases, the motor can only be designed at a certain speed with the longest working time in the working condition. Moreover, in order to take into account the motor torque at low speed and the efficiency at low speed, the maximum speed of the traditional single-winding motor is often limited. [0003] The low efficiency of the motor at low speed is caused by comprehensive factors, mainly for the following reasons: [0004] 1. Existing various types of motors use current to generate a magnetic field through a conductive coil, and use this magnetic field to interact with another magnetic field or magnetic circuit to generate torque to drive the mo...

AI Technical Summary

Problems solved by technology

[0015] 1. Requires n independent power supplies for power supply, which is costly and complicated in practical applications

Especially in battery-powered systems, multiple battery packs are used, which is a big trouble for charging and battery management

[0016] 2. The battery pack needs to be switched in parallel by a switch. If it is a battery-powered system, the voltage of the battery cannot be completely equal due to individual differences, and the internal resistance of the battery is very small, so there is a large difference in the process of parallel connection. Inrush current, it is easy to damage the switch and cause unreliability to the system

[0017] 3. In the case of windings with n greater than 2, there can only be two states of all in parallel or all in series, and there is no intermediate transition state, resulting in unsmooth switching of the motor

In the case of a large number of n, since the windings are all connected in series, the induced electromotive force of the winding itself will be added together, and the working speed range of the motor becomes very narrow when it is fully connected in series, and the purpose of widening the speed range of the motor cannot be achieved.

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