A Position Sensorless Control Technology for Four-Phase Doubly Salient Motor

Abstract

The invention discloses a position sensor-free control method for a four-phase doubly salient motor. During electric running of the four-phase doubly salient motor, counter potential vectors differ from each other by 90 degrees in sequence in a d-q coordinate system. The control method comprises the following steps of: partitioning N (N is a natural number of more than 2) rotating speed ranges for designing wave filters of corresponding cut-off frequencies, only acquiring the terminal voltages of any two adjacent phases, entering a subtractor for removing direct current bias, judging the rotating speed of a motor according to a potential zero crossing point at a certain moment, deciding to enter a wave filter of a certain cut-off frequency through the rotating speed ranges, and acquiring the waveform of potential passing through the wave filter by using a DSP (Digital Signal Processor); establishing a phase shift angle comparison table of a wave filter which corresponds to a certain range specific to different rotating speeds in the range for performing DSP inquiry and corresponding accurate phase shift; and obtaining a practical phase change position through a zero crossing comparator, performing DSP computation, and outputting a driving signal to a switch tube by using an FPGA (Field Programmable Gate Array) to complete phase change. The four-phase doubly salient motor can work in a wide rotating speed range.

Description

Technical field

[0001] The invention relates to a position sensorless control method for a four-phase double salient motor, which belongs to motor control technology. Background technique

[0002] With the development of motor design and control technology, accurate detection of rotor position has become one of the research hotspots in the field of motors at home and abroad. There are many kinds of control technologies. The conventional motor position detection technologies include: (1) direct position detection method; (2) conducting phase winding detection method; (3) non conducting phase winding detection method; (4) additional electrical Component detection method; (5) Detection method based on intelligent technology. In these methods, except for the direct position detection method, which directly detects the rotor position through special detection elements such as Hall sensors, the other methods are to find a parameter information that can be obtained to obtain the rotor ...

Examples

Embodiment Construction

[0053] The system structure diagram of this patent is as follows figure 1 As shown, it is mainly composed of five parts: (1) four-phase full-bridge power circuit module; (2) four-phase double salient motor; (3) subtractor module; (4) low-pass filter module; (5) Control module composed of DSP and FPGA.

[0054] Among them, the low-pass filter module includes N (N is a natural number greater than 2) kinds of low-pass filters with different cut-off frequencies. Every three filters with the same cut-off frequency are connected in series to form a three-stage filter, that is, a sixth-order filter pair. The collected back EMF is filtered. The main functions of the control module composed of DSP and FPGA are: (1) Calculate the speed at any time according to the zero-crossing voltage point of the phase A potential waveform; (2) Store a look-up table composed of angles that need to be compensated for different speeds in the same speed range, And select the angle to be compensated accord...

Technical field

[0001] The invention relates to a position sensorless control method for a four-phase double salient motor, which belongs to motor control technology. Background technique

[0002] With the development of motor design and control technology, accurate detection of rotor position has become one of the research hotspots in the field of motors at home and abroad. There are many kinds of control technologies. The conventional motor position detection technologies include: (1) direct position detection method; (2) conducting phase winding detection method; (3) non conducting phase winding detection method; (4) additional electrical Component detection method; (5) Detection method based on intelligent technology. In these methods, except for the direct position detection method, which directly detects the rotor position through special detection elements such as Hall sensors, the other methods are to find a parameter information that can be obtained to obtain the rotor ...

Examples

Embodiment Construction

[0053] The system structure diagram of this patent is as follows figure 1 As shown, it is mainly composed of five parts: (1) four-phase full-bridge power circuit module; (2) four-phase double salient motor; (3) subtractor module; (4) low-pass filter module; (5) Control module composed of DSP and FPGA.

[0054] Among them, the low-pass filter module includes N (N is a natural number greater than 2) kinds of low-pass filters with different cut-off frequencies. Every three filters with the same cut-off frequency are connected in series to form a three-stage filter, that is, a sixth-order filter pair. The collected back EMF is filtered. The main functions of the control module composed of DSP and FPGA are: (1) Calculate the speed at any time according to the zero-crossing voltage point of the phase A potential waveform; (2) Store a look-up table composed of angles that need to be compensated for different speeds in the same speed range, And select the angle to be compensated accord...

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