Alternating current motor driving control system and control method capable of lowering direct current side capacitance

Abstract

The invention relates to an alternating current motor driving control system and control method capable of lowering direct current side capacitance. Stator current is subjected to coordinate transformation to obtain a current component under a two-phase static coordinate system; after a current detection value and a rotating speed feedback value are obtained under a two-phase synchronous rotating coordinate system according to an electrical angle, a torque instruction value is obtained; after an alternating current input voltage passes through a phase-locked loop to obtain a current voltage phase, a current capacitive voltage given value and capacitance compensation current are further obtained; a given bus current instruction is obtained according to the torque instruction value and the current input voltage phase; a current reference value is obtained through calculation by a capacitance voltage loop PI regulator; after the given bus current is obtained by summation of the given bus current instruction, the current reference value and the capacitance compensation current, d axis and q axis current instruction values are obtained; the d axis and q axis current instruction values are compared with the current detection value and then are used as the input of the q axis and d axis current loop PI regulator; and three-phase voltage is output to a permanent magnetic synchronous motor through an SVPWM module and an inverter to drive the permanent magnetic synchronous motor to operate. The alternating current motor driving control system and control method can be widely applied to the field of an alternating current motor control technology.

Description

technical field [0001] The present invention relates to an AC motor drive control system and control method, in particular to an AC motor drive control system and control method for reducing DC side capacitance applied in the technical field of AC motor control. Background technique [0002] In recent years, with the development of AC motor drive technology and power electronics technology, AC motors have been widely used in various fields such as industry, aerospace and home appliances. Such as figure 1 As shown, in order to maintain a constant bus voltage, the commonly used AC motor drive system generally has a large-capacity bus capacitor on the DC bus. However, the existence of large-capacity bus capacitors brings the following problems to the system: First, large-scale DC capacitors generally use electrolytic capacitors, and their life is generally short. Therefore, the existence of electrolytic capacitors seriously affects the life of the overall system. At present, ...

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Problems solved by technology

However, the existence of large-capacity bus capacitors brings the following problems to the system: First, large-scale DC capacitors generally use electrolytic capacitors, and their life is generally short. Therefore, the existence of electrolytic capacitors seriously affects the life of the overall system

However, in the inverter motor drive system, due to the switching characteristics of the inverter bridge, the bus current and power are not continuous

In addition, the above methods all need to filter the bus current and power with a lower cut-off frequency, so a large delay in the system is inevitable

At the same time, due to the lack of control over the current and voltage, the bus voltage is easy to become negative, which affects the reliability of the system

Therefore, there are still many problems in the research on the control strategy of the AC motor drive system that reduces or cancels the DC side capacitance, and there is a lack of practical solutions.

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