Frequency variable speed-adjusting device for both end power supplying multi-phase AC motor

Abstract

The invention discloses a double-end-electrified multi-phase alternating current motor variable-frequency control device, which comprises a multi-phase alternating current motor, wherein the m head ends and the m tail ends of the stator winding of the multi-phase alternating current motor are led out to respectively connect with a multi-phase univertor, and the multi-phase univertor is formed by a direct current power supply, a filter capacitance, a multi-phase inverter and a variable-frequency controller, and the phase number m of the multi-phase alternating current motor is equal to that of the multi-phase inverter, wherein m>=5. The double-end-electrified multi-phase alternating current motor variable-frequency control device of the invention not only can realize large power by using a power electronic component with limited single-tube capacity in a larger range, but also has higher reliability as having redundancy on phase units and a system.

Description

technical field [0001] The invention relates to a variable-frequency speed-regulating device for an AC motor, in particular to a frequency-variable speed-regulating device for a multi-phase AC motor with more than three phases. Background technique [0002] Three-phase AC frequency conversion speed control device has been widely used in small and medium power motors. Its basic structure is as follows: figure 1 shown. 1 in the figure is an AC motor (synchronous or asynchronous); one end of the stator winding of the three-phase AC motor 1 leads to a three-phase inverter 2, and the three-phase inverter 2 is composed of three bridge arms; C is a filter capacitor; E is DC power is generally obtained through rectification. [0003] In the small and medium power frequency conversion speed regulation system, the structure of the bridge arm is as follows: figure 2 shown. The switching device in the figure adopts fully controlled power electronic devices such as IGBT or IGCT. Du...

AI Technical Summary

Problems solved by technology

The limitation of this scheme is that due to the manufacturing process and other reasons, the number of phases cannot be very large (the number of phases used in general is m≤15), so the power range that can be realized is also limited; the second is that although this scheme is in the motor There is redundancy at the level of phase numbers output by the frequency converter, but there is no redundancy at the system level. Once the DC power supply E or the controller of the inverter fails, the system cannot continue to run

Images