阅读说明：本技术 无刷直流电机转速指示装置及指示方法 (Brushless direct current motor rotating speed indicating device and indicating method ) 是由 梁裕 魏海峰 王浩陈 刘维亭 张懿 于 2019-10-17 设计创作，主要内容包括：本发明公开了一种无刷直流电机转速指示装置及指示方法,包括驱动模块、无刷直流电机的三相定子绕组、控制器,驱动模块与无刷直流电机的三相定子绕组连接；控制器的6个IO接口P1-P6分别和驱动模块的6个栅极输入相连；控制器的6个IO接口P7-P12在PWM无效时间内发送脉冲,改变电机转子瞬时的受力情况,用于电机相对于初始位置振动发音。其中使用方法包括：在控制器通过PWM控制电机转速时,利用PWM无效的时间,通过控制器的接口P7-P12提供给MOS管脉冲,使电机振动发音；且PWM无效时间越长,提供给MOS管的脉冲越宽,电机振动越强烈,产生的音量越大,继而起到转速指示的作用。(The invention discloses a brushless direct current motor rotating speed indicating device and an indicating method, comprising a driving module, a three-phase stator winding of a brushless direct current motor and a controller, wherein the driving module is connected with the three-phase stator winding of the brushless direct current motor; 6 IO interfaces P1-P6 of the controller are respectively connected with 6 grid inputs of the driving module; 6 IO interfaces P7-P12 of the controller send pulses in PWM dead time, change the instantaneous stress condition of the motor rotor, and are used for vibrating and sounding the motor relative to the initial position. The using method comprises the following steps: when the controller controls the rotating speed of the motor through PWM, the invalid PWM time is provided for MOS tube pulses through interfaces P7-P12 of the controller, so that the motor vibrates and sounds; and the longer the PWM invalid time, the wider the pulse provided for the MOS tube, the stronger the motor vibration, the larger the generated sound volume, and then the rotating speed indication function is played.)

1. The utility model provides a brushless DC motor rotational speed indicating device which characterized in that, includes drive module, brushless DC motor's three-phase stator winding, controller, wherein: the driving module is connected with a three-phase stator winding of the brushless direct current motor and is used for driving the motor to rotate and vibrate; 6 IO interfaces P1-P6 of the controller are respectively connected with 6 grid inputs of the driving module and used for sending PWM to the grids of 6 MOS tubes so that the motor can normally rotate; 6 IO interfaces P7-P12 of the controller send pulses in PWM invalid time, change the instantaneous stress condition of the motor rotor and are used for vibrating and sounding the motor relative to the initial position.

2. The device for indicating the rotating speed of the brushless direct current motor according to claim 1, wherein the driving module comprises a direct current power source VDC, a MOS tube S1, a MOS tube S2, a MOS tube S3, a MOS tube S4, a MOS tube S5, a MOS tube S6, a MOS tube S7, a MOS tube S8, a MOS tube S9, a MOS tube S10, a MOS tube S11, a MOS tube S12; the positive electrode of the direct-current power supply VDC is respectively connected with the drain electrode of the MOS tube S1, the drain electrode of the MOS tube S3, the drain electrode of the MOS tube S5, the drain electrode of the MOS tube S7, the drain electrode of the MOS tube S9 and the drain electrode of the MOS tube S11; the negative electrode of the direct current power supply is respectively connected with the source electrode of the MOS tube S4, the source electrode of the MOS tube S6, the source electrode of the MOS tube S2, the source electrode of the MOS tube S8, the source electrode of the MOS tube S10 and the source electrode of the MOS tube S12; the source of the MOS tube S1, the source of the MOS tube S7, the drain of the MOS tube S4, the drain of the MOS tube S8 and A in the three-phase stator winding of the brushless direct current motor are connected, the source of the MOS tube S1 is connected with the drain of the MOS tube S4, and the source of the MOS tube S7 is connected with the drain of the MOS tube S8; the source of the MOS tube S3, the drain of the MOS tube S6, the source of the MOS tube S9, the drain of the MOS tube S10 and the B in the three-phase stator winding of the brushless direct current motor are connected, the source of the MOS tube S3 is connected with the drain of the MOS tube S6, and the source of the MOS tube S9 is connected with the drain of the MOS tube S10; the source electrode of the MOS tube S5, the drain electrode of the MOS tube S2, the source electrode of the MOS tube S11, the drain electrode of the MOS tube S12 and the C in the three-phase stator winding of the brushless direct current motor are connected, the source electrode of the MOS tube S5 is connected with the drain electrode of the MOS tube S2, and the source electrode of the MOS tube S11 is connected with the drain electrode of the MOS tube S12.

3. The apparatus of claim 2, wherein the controller comprises interfaces P1, P2, P3, P4, P5, P6, P7, P8, P9, P10, P11, P12; the gate of the MOS tube S1 is connected with the interface P1 of the controller, and the gate of the MOS tube S7 is connected with the interface P7 of the controller; the gate of the MOS tube S2 is connected with the interface P2 of the controller, and the gate of the MOS tube S12 is connected with the interface P12 of the controller; the gate of the MOS tube S3 is connected with the interface P3 of the controller, and the gate of the MOS tube S9 is connected with the interface P9 of the controller; the gate of the MOS tube S4 is connected with the interface P4 of the controller, and the gate of the MOS tube S8 is connected with the interface P8 of the controller; the gate of the MOS tube S5 is connected with the interface P5 of the controller, and the gate of the MOS tube S11 is connected with the interface P11 of the controller; the gate of the MOS transistor S6 is connected to the interface P6 of the controller, and the gate of the MOS transistor S10 is connected to the interface P10 of the controller.

4. A method for indicating a rotational speed indicating apparatus of a brushless dc motor, using the rotational speed indicating apparatus of a brushless dc motor according to claim 3, comprising the steps of: the method comprises the following steps: setting a PWM period and PWM effective time of a controller; step two: and sending pulses through an IO interface of the controller in the PWM invalid time, wherein the pulse duration accounts for 3% -8% of the PWM invalid time, and the width H of the sent pulses can be calculated by the following formula:(ii) a Where T is the PWM period, K is the PWM duty cycle, and C is the percentage of the pulse sent to the PWM dead time.

Technical Field

The invention belongs to the technical field of brushless direct current motors, and particularly relates to a rotating speed indicating device and a rotating speed indicating method of a brushless direct current motor.

Background

Brushless dc motors have been widely used in recent years, and have the characteristics of simple control, high efficiency, good speed regulation performance, and large output torque. The application and research of the brushless direct current motor are widely regarded in occasions and fields with high requirements on the performance and the control precision of the motor, such as robots, aerospace, precise electronic instruments and equipment, and the like.

At present, for some devices which adopt three-stage rotating speed control like water pumps, fans and the like to operate by direct current motors in the market, the operation state of the brushless direct current motor cannot be judged mostly, and the rotating speed state of the motor cannot be known qualitatively.

In order to solve the problem, the conventional method is to add a sensor on a rotating shaft of a brushless direct current motor to realize speed measurement or paste reflective paper on the rotating shaft and then use a photoelectric speed meter to measure, but the former increases hardware cost, and the latter can bring larger rotating speed measurement errors. And only the brushless direct current motor body is used for vibrating and sounding, so that the state of the rotating speed can be qualitatively determined, and based on the state, the PWM for controlling the motor can be used for sending pulses in the PWM invalid time, changing the tone and the voice frequency of the generated voice, and designing a three-section rotating speed indicating device.

Disclosure of Invention

The invention aims to solve the problem that three-stage rotating speed indication of a brushless direct current motor is difficult in the prior art.

In order to achieve the purpose, the invention discloses a three-stage rotating speed prompting device and an indicating method of a brushless direct current motor, and the specific technical scheme is as follows: a brushless direct current motor rotating speed indicating device comprises a driving module, a three-phase stator winding of a brushless direct current motor and a controller; the driving module is connected with a three-phase stator winding of the brushless direct current motor and is used for driving the motor to rotate and vibrate; 6 IO interfaces P1-P6 of the controller are respectively connected with 6 grid inputs of the driving module and used for sending PWM to the grids of the 6 MOS tubes so that the motor can normally rotate; 6 IO interfaces P7-P12 of the controller send pulses in PWM dead time, change the instantaneous stress condition of the motor rotor, and are used for vibrating and sounding the motor relative to the initial position.

In a further improvement of the invention, the driving module comprises a direct current power supply VDC, a MOS tube S1, a MOS tube S2, a MOS tube S3, a MOS tube S4, a MOS tube S5, a MOS tube S6, a MOS tube S7, a MOS tube S8, a MOS tube S9, a MOS tube S10, a MOS tube S11 and a MOS tube S12; the positive electrode of the direct-current power supply VDC is respectively connected with the drain electrode of the MOS tube S1, the drain electrode of the MOS tube S3, the drain electrode of the MOS tube S5, the drain electrode of the MOS tube S7, the drain electrode of the MOS tube S9 and the drain electrode of the MOS tube S11; the negative electrode of the direct current power supply is respectively connected with the source electrode of the MOS tube S4, the source electrode of the MOS tube S6, the source electrode of the MOS tube S2, the source electrode of the MOS tube S8, the source electrode of the MOS tube S10 and the source electrode of the MOS tube S12; the source electrode of the MOS tube S1, the source electrode of the MOS tube S7, the drain electrode of the MOS tube S4 and the drain electrode of the MOS tube S8 are connected with A in the three-phase stator winding of the brushless direct current motor, the source electrode of the MOS tube S1 is connected with the drain electrode of the MOS tube S4, and the source electrode of the MOS tube S7 is connected with the drain electrode of the MOS tube S8; the source electrode of the MOS tube S3, the drain electrode of the MOS tube S6, the source electrode of the MOS tube S9 and the drain electrode of the MOS tube S10 are connected with B in a three-phase stator winding of the brushless direct current motor, the source electrode of the MOS tube S3 is connected with the drain electrode of the MOS tube S6, and the source electrode of the MOS tube S9 is connected with the drain electrode of the MOS tube S10; the source electrode of the MOS tube S5, the drain electrode of the MOS tube S2, the source electrode of the MOS tube S11 and the drain electrode of the MOS tube S12 are connected with the C in the three-phase stator winding of the brushless direct current motor, the source electrode of the MOS tube S5 is connected with the drain electrode of the MOS tube S2, and the source electrode of the MOS tube S11 is connected with the drain electrode of the MOS tube S12.

In a further development of the invention, the controller comprises: interfaces P1, P2, P3, P4, P5, P6, P7, P8, P9, P10, P11, P12; the gate of the MOS tube S1 is connected with the interface P1 of the controller, and the gate of the MOS tube S7 is connected with the interface P7 of the controller; the gate of the MOS tube S2 is connected with the interface P2 of the controller, and the gate of the MOS tube S12 is connected with the interface P12 of the controller; the gate of the MOS tube S3 is connected with the interface P3 of the controller, and the gate of the MOS tube S9 is connected with the interface P9 of the controller; the gate of the MOS tube S4 is connected with the interface P4 of the controller, and the gate of the MOS tube S8 is connected with the interface P8 of the controller; the gate of the MOS tube S5 is connected with the interface P5 of the controller, and the gate of the MOS tube S11 is connected with the interface P11 of the controller; the gate of the MOS transistor S6 is connected to the interface P6 of the controller, and the gate of the MOS transistor S10 is connected to the interface P10 of the controller.

The invention also provides an indication method of the brushless direct current motor rotating speed indication device, which comprises the following specific steps:step 1: setting a PWM period and PWM effective time of a controller; step 2: the pulse is sent through an IO interface of the controller within PWM invalid time, the pulse duration accounts for 3% -8% of the PWM invalid time, and with the difference of the PWM invalid time, the pulse width sent by the IO interface is different, and sounds with different loudness are generated; alternatively, the width H of the transmitted pulse may be calculated by the following equation:. Where T is the PWM period, K is the PWM duty cycle, and C is the percentage of the pulse sent to the PWM dead time.

Optionally, the duration of the sent pulse accounts for 3% -8% of the PWM dead time, so that the motor generates clear sound in the pulse duration, when the rotating speed is reduced, the PWM dead time is shortened, the dead time is lengthened, the pulse width provided for the MOS tube accounts for 3% -8% of the PWM dead time, and the motor vibrates to generate sound; on the contrary, when the rotating speed is increased, the PWM effective time is prolonged, the invalid time is shortened, the pulse width provided for the MOS tube accounts for 3% -8% of the PWM invalid time, the pulse is narrower than that when the rotating speed is reduced, the motor vibration is weakened, the generated volume is smaller than that when the rotating speed is reduced, and therefore the rotating speed indicating effect is achieved.

The beneficial effect of this hair: 1. under the condition of not using an additional rotating speed detection device, PWM and pulse are sent out only by different IO interfaces of the controller, so that the motor vibrates and pronounces when running normally, and the effect of rotating speed indication is realized by a very simple method; 2. the pulse duration time of the given pulse accounts for 3% -8% of the PWM invalid time by utilizing the PWM invalid time to pulse the corresponding MOS transistor, and the effect is achieved as follows: the slower the rotating speed is, the longer the PWM invalid time is, the wider the pulse sent by the IO interface is, and the larger the generated volume is; conversely, the rotation speed is increased, the PWM dead time is shortened, and the narrower the pulse sent by the IO interface is, the smaller the generated sound volume is.

Drawings

Fig. 1 is a schematic circuit diagram of a rotation speed indicating device of a brushless dc motor according to the present invention.

Fig. 2 is a flow chart of an indicating method of the rotating speed indicating device of the brushless dc motor according to the present invention.

Fig. 3 is a diagram showing the relationship between the PWM inactive time and the single pulse condition a of the apparatus for indicating the rotation speed of a brushless dc motor according to the present invention.

Fig. 4 is a diagram illustrating the relationship between the PWM inactive time and the single pulse condition B of the apparatus for indicating the rotational speed of a brushless dc motor according to the present invention.

Detailed Description

For the purpose of enhancing the understanding of the present invention, the present invention will be described in further detail with reference to the accompanying drawings and examples, which are provided for the purpose of illustration only and are not intended to limit the scope of the present invention.