A pulse width modulation control method and system for a switched reluctance motor
A switched reluctance motor and pulse width modulation technology, which is applied in the direction of speed/torque control of a single motor, can solve the problems of increased motor torque ripple, increased motor winding current ripple, and decreased speed stability. The effect of small specific gravity, protection of IGBT, and avoidance of short turn-on time
Inactive Publication Date: 2016-03-30
NIDEC BEIJING DRIVE TECH CO LTD
View PDF6 Cites 0 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Although the above method can prevent the IGBT conduction time from being too short, the current pulsation of the motor winding will increase when the load is no-load or the load is small, so that the torque pulsation of the motor will increase, resulting in a decrease in the speed stability when the load is no-load or the load is small.
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0029] The invention realizes that when the switched reluctance motor is controlled by the pulse width modulation technology PWM, under the condition of no load or very small load, the conduction time of the IGBT is maintained within a certain time by means of frequency conversion, and the no-load or load is reduced. When the load is small, the proportion of IGBT switching loss is not increased, and the torque ripple of the motor is not increased when the load is small or the load is small.
[0030] The present invention realizes that under the condition of no load or very small load, the conduction time of IGBT is greater than the minimum allowable value, as shown in the accompanying drawing Figure 5 As shown, T1 and T2 are the PWM cycles before and after frequency conversion respectively. Before frequency conversion, ton1 is the minimum allowable IGBT turn-on time. After frequency conversion, the PWM cycle becomes T2, and the IGBT turn-on time becomes ton2. At this time, ton...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
Login to View More Abstract
The invention discloses a method and system for pulse width modulation control of a switched reluctance machine. The method includes the steps of firstly, acquiring duty cycle output by a current regulator; secondly, performing hysteresis comparison to the duty cycle output by the current regulator, outputting a PWM (pulse width modulation) control signal with a first frequency when the duty cycle output by the current regulator drops from a second preset value to a first preset value; and outputting a second PWM control signal with a second frequency larger than the first frequency when the duty cycle output by the current regulator rises from the first preset value to the second preset value; and thirdly, controlling torque of the switched reluctance machine through an actuator according to the PWM control signals. On time of an IGBT (insulated gate bipolar translator) is kept within an appropriate time range, and accordingly proportion of switching loss of the IGBT during no-load or small load is reduced, on time of the IGBT is avoided being too short, and the IGBT is protected.
Description
technical field [0001] The invention relates to the field of switched reluctance motor control, in particular to a pulse width modulation control method and system for a switched reluctance motor. Background technique [0002] At present, pulse width modulation (PWM) is often used in the control mode of switched reluctance motors. In the existing control mode, the frequency of PWM is fixed. By adjusting the duty ratio of PWM, the control of the motor winding current is realized, thereby Realize the control of the torque of the switched reluctance motor. However, when fixed-frequency PWM is used for control, the PWM duty cycle will be very small when no-load or load is small, and the conduction time of the insulated gate bipolar transistor (IGBT) is very short, and the IGBT is almost in the entire conduction time In the transition state of turn-on and turn-off, a large part of the energy is consumed in the switching loss of the IGBT, and it has a great impact on the life of ...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More Patent Type & Authority Patents(China)
IPC IPC(8): H02P6/08
Inventor 蒋哲周海亮彭永强
Owner NIDEC BEIJING DRIVE TECH CO LTD