CN201601643U - Controller for 120-degree non-square-wave type brushless direct-current motor - Google Patents

Abstract

The utility model discloses a controller for a 120-degree non-square-wave type brushless direct-current motor, which relates to a controller for a direct-current motor. The motor is easy to have torque fluctuation, and even have obvious running noise under the serious condition when the conventional controller controls the rotation of the motor. The controller for the 120-degree non-square-wave type brushless direct-current motor comprises a rotor position analyzing module for realizing the position analysis of the motor rotor, a control voltage calculating module which is connected with the rotor position analyzing module and used for calculating corresponding control voltage value obtained according to the position of the rotor, a PWM output module which is connected with the control voltage calculating module and used for generating corresponding 120-degree PWM control waveform according to the control voltage value, and a power driving unit which is positioned between the motor and the PWM output module and used for controlling the running of the motor according to the PWM control waveform. The value of control voltage in a control interval is adjusted in real time according to the position of the torque so as to reduce the fluctuation of torque, and simultaneously, the torque fall caused by the replacement of the control interval can be effectively weakened.

Description

120 degree non-square wave type brushless direct current motor controllers

[technical field]

The utility model relates to control of DC, refers to a kind of 120 degree non-square wave type brushless direct current motor controller and control methods especially.

[background technology]

In the control of brshless DC motor, 120 degree square wave brshless DC motor control modes are a kind of very common control modes at present.Determine the Electric Machine Control phase sequence according to rotor-position, an electric cycle is divided into six and claps control, and each bat is called a control interval.The factor that produces torque ripple during brshless DC motor control mainly is two: the one, and the moment torque that control interval causes when changing is fallen; Another is in the control interval because control voltage can not be adjusted the fluctuation that its numerical value causes torque in real time along with rotor-position.Because the motor opposite potential of actual production generally is sinusoidal wave shape or flat-topped waveform, or even saddle-shaped waveform, be difficult to the square-wave waveform of the standard of accomplishing, wherein comprise abundant harmonic wave, when adopting 120 degree square wave controls, can not carry out suitable adjustment along with the physical location of rotor owing to control the magnitude of voltage size in any one control interval, guarantee the stationarity of motor output torque, so cause motor torque ripple in running, to occur, tangible running noises can occur when serious; And same 120 degree square wave controlling schemes are by when controlling with the motor of a series of iron cores, different capacity grade, and the less motor running noises of power grade shows not obvious, and the motor running noises performance that power grade is high more is then obvious more.

[utility model content]

The technical assignment of the technical problems to be solved in the utility model and proposition is that the prior art scheme is improved and improved, provide a kind of 120 degree non-square wave type brushless direct current motor controllers, to reach the stationarity that improves each control interval internal torque output when the torque of changing generation because of control interval is fallen reducing.For this reason, the utility model is taked following technical scheme:

120 degree non-square wave type brushless direct current motor controllers, it is characterized in that: it comprises

The rotor-position parsing module is used to realize the motor rotor position parsing;

Control voltage computing module, it is connected with the rotor parsing module, is used for calculating corresponding control magnitude of voltage according to rotor-position;

The PWM output module, it is connected with control voltage computing module, is used for generating corresponding 120 degree pwm waveforms according to the control magnitude of voltage;

Power drive unit between motor and PWM output module, is used for according to pwm waveform control motor rotation.

Control voltage computing module calculates each interval magnitude of voltage according to rotor-position, improves motor current waveform effectively, the torque ripple when torque ripple when reducing the motor operation and commutation.

As the further of technique scheme improved and replenish, the utility model also comprises following additional technical feature:

Controller also comprises detection module, is used for the position of detection rotor, and it links to each other with the rotor-position parsing module.

Described detection module comprises the position brick sensor of being located in the motor, and the lead-out wire of described position transducer links to each other with the rotor-position parsing module.

The memory cell that control voltage computing module and is used to deposit the corresponding bucking voltage value of each control interval is connected, and described memory cell is connected with the PWM output module.

Controller also comprises output module, is used to show electric machine operation state.

Beneficial effect: the control voltage in control interval is adjusted its numerical value to reduce the fluctuation of torque in real time according to rotor-position, also can effectively weaken the torque that causes when control interval is changed simultaneously and fall.

[description of drawings]

Fig. 1 is the utility model structure principle chart;

Fig. 2 is the utility model workflow diagram;

Fig. 3 is the current waveform figure before the voltage compensation;

Fig. 4 is the current waveform figure behind the voltage compensation.

[embodiment]

Below in conjunction with Figure of description the technical solution of the utility model is described in further detail.

As shown in Figure 1, the utility model comprises: the rotor-position parsing module is used to realize the motor rotor position parsing; Control voltage computing module, it is connected with the rotor parsing module, is used for calculating corresponding control magnitude of voltage according to rotor-position; The PWM output module, it is connected with control voltage computing module, is used for generating corresponding 120 degree pwm waveforms according to the control magnitude of voltage; Power drive unit between motor and PWM output module, is used for according to pwm waveform control motor rotation; Detection module is used for the position of detection rotor, and it links to each other with the rotor-position parsing module, and detection module can comprise the position transducer of being located in the motor, and the lead-out wire of position transducer links to each other with the rotor-position parsing module.Certainly controller also can be set up a memory cell that is used to deposit the corresponding bucking voltage value of each control interval, its with control voltage computing module and PWM output module and be connected, and set up the output module that is used to show electric machine operation state.The rotor-position parsing module is realized the motor rotor position parsing, obtain rotor angle accurately, and this angle value sent to control voltage computing module, calculate control magnitude of voltage required to should rotor angle the time, produce corresponding 120 degree pwm waveforms by the PWM output module, the output of power controlling driver element reaches the purpose of controlling motor.

As shown in Figure 2,120 degree non-square wave type brushless direct current motor control methods may further comprise the steps:

1) position probing step is used for the detection rotor position;

2) analyzing step is resolved the rotor position information that detection obtains;

3) calculation control voltage module, according to the rotor position information calculation control voltage of resolving, the control voltage module is with sinusoidal waveform electromotive force calculation control voltage, with formula:

Or with fitting formula:

$u=\underset{n=N_0}{\overset{n=N_1}{\mathrm{\Σ}}}{A}_{n}f\left({\sin }^n\left(\mathrm{\θ}\right)\right)+\underset{n=N_2}{\overset{n=N_3}{\mathrm{\Σ}}}{B}_{n}f\left({\cos }^n\left(\mathrm{\θ}\right)\right)$

Calculate;

4) computed duty cycle is calculated required PWM duty ratio size according to control voltage, generates corresponding 120 degree pwm waveforms;

5) actuation step turns round by the power cell drive motors according to pwm waveform.

Before calculation control voltage, any opposite potential waveform is carried out fourier decomposition, obtain different harmonic component ratios, the control voltage module is calculated control voltage according to the different humorous proportional meters that involves.

As shown in Figure 3, adopt the utility model preceding actual measurement electric machine phase current waveform and dc bus current oscillogram, second channel is a phase current waveform, and visible electric current has tangible spike, and this is the root that causes torque ripple.First passage is the bus current waveform, and the electric current drop-out time was longer when visible control interval was changed, and is bigger to the torque influence.As shown in Figure 4, behind enforcement the utility model, the electric current crest of the phase current waveform of first passage reduces greatly, and current waveform is done the waveform adjustment along with angle changes, and meets the compensated torque requirement.The bus current waveform of second channel electric current when commutation falls part and obviously reduces.

Claims (5)

1.120 the degree non-square wave type brushless direct current motor controller is characterized in that: it comprises

The rotor-position parsing module is used to realize the motor rotor position parsing;

Control voltage computing module, it is connected with the rotor parsing module, is used for calculating corresponding control magnitude of voltage according to rotor-position;

The PWM output module, it is connected with control voltage computing module, is used for generating corresponding 120 degree pwm waveforms according to the control magnitude of voltage;

Power drive unit between motor and PWM output module, is used for according to pwm waveform control motor rotation.

2. 120 degree non-square wave type brushless direct current motor controllers according to claim 1, it is characterized in that: controller also comprises detection module, is used for the position of detection rotor, it links to each other with the rotor-position parsing module.

3. 120 degree non-square wave type brushless direct current motor controllers according to claim 2, it is characterized in that: described detection module comprises the position transducer of being located in the motor, and the lead-out wire of described position transducer links to each other with the rotor-position parsing module.

4. according to the described 120 degree non-square wave type brushless direct current motor controllers of the arbitrary claim of claim 1-3, it is characterized in that: the memory cell that control voltage computing module and is used to deposit the corresponding bucking voltage value of each control interval is connected, and described memory cell is connected with the PWM output module.

5. 120 degree non-square wave type brushless direct current motor controllers according to claim 4, it is characterized in that: controller also comprises output module, is used to show electric machine operation state.

Images