Brushless double-fed motor super-synchronization speed control system and motor field orientation vector control method and motor direct torque control method for brushless double-fed motor super-synchronization speed control system

Abstract

The invention discloses a brushless double-fed motor super-synchronization speed control system and a motor field orientation vector control method and motor direct torque control method for the brushless double-fed motor super-synchronization speed control system. The speed control system comprises a power supply source, a motor stator, a motor rotor, a transformer, a rectifier, a converter, a starting resistor, a drive unit, a controller, a switch K1 and a switch K2, wherein a primary winding and a secondary winding are arranged in the stator; the primary winding is connected with the power supply source; the secondary winding is connected with the power supply source through the switch K2, the converter, the rectifier and the transformer; in the motor starting process, the switch K1 is closed, the secondary winding is connected to the starting resistor in series, the switch K2 is opened and connection of the converter and the secondary winding is cut off; when the rotating speed of the motor is close to a synchronous rotating speed, the switch K1 is opened, the switch 2 is closed and the secondary wining cuts off the starting resistor and communicates with the converter. The brushless double-fed motor super-synchronization speed control system carries out super-synchronization one-way speed control above the synchronous rotating speed by adopting the motor field orientation vector control method and the direct torque control method, and the cost of the required converter is relatively low.

Description

technical field [0001] The invention relates to an AC motor speed regulation system, in particular to a super synchronous speed regulation system of a brushless double-fed motor, a motor field-oriented vector control method, and a motor direct torque control method. Background technique [0002] There are two main types of existing AC motor speed regulation methods, one is to adjust the motor speed through the variable frequency power supply for the stator winding, this speed regulation method is suitable for synchronous motors (electrically excited synchronous motors, permanent magnet synchronous motors, reluctance motors) etc.) and cage induction motor; the other is the double-fed speed regulation method in which the stator winding and rotor winding of the wound rotor induction motor are respectively powered by a fixed power frequency power supply and a variable frequency power supply; the advantage of the first speed regulation method is versatility Strong, flexible contr...

AI Technical Summary

Problems solved by technology

[0005] ② From the perspective of frequency converter and control technology, the control technology of "two-way speed regulation" from sub-synchronous to super-synchronous for brushless doubly-fed motors is relatively complicated, and a frequency converter with two-way variable current is required, and the cost is relatively high

Regardless of the operation mode of the motor and the generator of the brushless doubly-fed motor, the phase sequence and power flow direction of the three-phase current in the auxiliary winding (control winding) in the sub-synchronous speed zone and the super-synchronous speed zone are opposite, so from sub-synchronous to super-synchronous The "two-way speed regulation" needs the power supply of the "two-way variable current" inverter, and its hardware and software structure and control technology are much more complicated than those that only need "one-way speed regulation".

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