A kind of calculation method and computing device of motor speed
阅读说明：本技术 一种电机转速的计算方法及计算装置 (A kind of calculation method and computing device of motor speed ) 是由 苗会彬 陶喆 刘海珍 朱心放 施雯 田佰辉 王建俊 于 2019-08-30 设计创作，主要内容包括：本发明实施例提供了一种电机转速的计算方法及计算装置,所述电机转动的计算方法包括：计算电机的第一转速；当第一转速小于预设转速时,根据电机转动设定转动角度的时间确定所述电机的第二转速,并以第二转速作为电机的实际转速。本发明实施例提供的电机转速的计算方法,解决了电机在低转速时转速计算不准的问题,提高了电机系统的控制精度,改善电动助力刹车装置的性能。(The embodiment of the invention provides a kind of calculation method of motor speed and computing device, the calculation method of the motor rotation includes: the first revolving speed for calculating motor；When the first revolving speed is less than preset rotation speed, the second revolving speed of the motor is determined according to the time that motor rotates setting rotational angle, and using the second revolving speed as the actual speed of motor.The calculation method of motor speed provided in an embodiment of the present invention solves the problems, such as that motor tachometer in the slow-speed of revolution is not calculated accurately, improves the control precision of electric system, improve the performance of electric boosted brake gear.)
1. a kind of calculation method of motor speed characterized by comprising
Calculate the first revolving speed of motor；
When first revolving speed is less than preset rotation speed, the motor is determined according to the time that motor rotates setting rotational angle Second revolving speed, and using second revolving speed as the actual speed of the motor.
2. calculation method according to claim 1, which is characterized in that when first revolving speed is less than preset rotation speed, root The second revolving speed of the motor is determined according to the time that motor rotates setting rotational angle, comprising:
When the first revolving speed v meets v < 50rpm, the second revolving speed of the motor is determined according to the time that motor rotates 45 °；
When the first revolving speed v meets 50rpm≤v≤300rpm, the motor is determined according to the time that motor rotates 180 ° The second revolving speed.
3. calculation method according to claim 2, which is characterized in that when the first revolving speed v meets v < 50rpm, root The second revolving speed of the motor is determined according to the time that motor rotates 45 °, comprising:
Based on magnetoresistive sensor obtain motor rotation when motor turn signal, the motor turn signal include sinusoidal signal and Cosine signal；
Determine that the motor rotates 45 ° of time Δ T according to the sinusoidal signal and cosine signal45°, using formula S pd2= 1000*60*(45/360)/ΔT45°Calculate the second revolving speed of the motor；
When the first revolving speed v meets 50rpm≤v≤300rpm, the motor is determined according to the time that motor rotates 180 ° The second revolving speed, comprising:
Motor turn signal when motor rotation is obtained based on magnetoresistive sensor, the motor turn signal includes sinusoidal signal And/or cosine signal；
Determine that the motor rotates 180 ° of time Δ T according to the sinusoidal signal and/or cosine signal180°, using formula S pd2 =1000*60* (180/360)/Δ T180°Calculate the second revolving speed of the motor.
4. calculation method according to claim 3, which is characterized in that the sinusoidal signal includes the first sinusoidal signal and the Two sinusoidal signals, the cosine signal include the first cosine signal and the second cosine signal；
Determine that the motor rotates 45 ° of time Δ T according to the sinusoidal signal and cosine signal45°, comprising:
Determine sine difference signal according to first sinusoidal signal and the second sinusoidal signal, according to first cosine signal and Second cosine signal determines cosine differential signal；
Determine that the motor rotates 45 ° of time Δ T according to the sine difference signal and the cosine differential signal45°；
Determine that the motor rotates 180 ° of time Δ T according to the sinusoidal signal and/or cosine signal180°, comprising:
Determine sine difference signal according to first sinusoidal signal and the second sinusoidal signal, according to first cosine signal and Second cosine signal determines cosine differential signal；
Determine that the motor rotates 180 ° of time Δ T according to the sine difference signal and/or the cosine differential signal180°。
5. calculation method according to claim 4, which is characterized in that poor according to the sine difference signal and the cosine Sub-signal determines that the motor rotates 45 ° of time Δ T45°, comprising:
First time T1 is determined according to the initial time of the sine difference signal and the cosine differential signal；
The second time T2 is determined according to the sine difference signal and the cosine differential signal time equal for the first time；
45 ° of time, i.e. Δ T are rotated using the difference between second time and the first time as the motor45°= T2-T1；Alternatively,
According to the sine difference signal and the cosine differential signal, the time equal for the first time determines first time T1 '；
According to the sine difference signal and the cosine differential signal again equal time as the second time T2 '；
The time that the motor rotates 45 °, i.e. Δ T are calculated with the difference between second time and the first time45°= (T2'-T1')/4；
Determine that the motor rotates 180 ° of time Δ T according to the sine difference signal and the cosine differential signal180°, packet It includes:
Third time T3 is determined according to the initial time of the sine difference signal；
According to the sine difference signal, the null time determines the 4th time T4 for the first time；
180 ° of time, i.e. Δ T are rotated using the difference between the 4th time and the third time as the motor180° =T4-T3；And/or
According to the cosine differential signal, the null time determines third time T3 ' for the first time；
The 4th time T4 ' is determined according to the time that the cosine differential signal is again equal to zero；
180 ° of time, i.e. Δ T are rotated using the difference between the 4th time and the third time as the motor180° =T4 '-T3 '.
6. calculation method according to claim 1, which is characterized in that calculate the first revolving speed of motor, comprising:
Obtain rotational angle Δ θ of the motor in certain time Δ T；
Using formula S pd1=1000*60* (Δ θ/360)/Δ T calculates the first revolving speed of the motor.
7. calculation method according to claim 6, which is characterized in that the calculation method further include:
When first revolving speed is greater than the preset rotation speed, using first revolving speed as the actual speed of the motor.
8. a kind of computing device of motor speed characterized by comprising
First revolving speed computing module, for calculating the first revolving speed；
Actual speed determining module, for rotating setting angle of rotation according to motor when first revolving speed is less than preset rotation speed The time of degree determines the second revolving speed of the motor, and using second revolving speed as the actual speed of the motor.
9. computing device according to claim 8, which is characterized in that the actual speed determining module includes first determining Submodule and second determines submodule；
Described first determines that submodule is used for when the first revolving speed v meets v < 50rpm, and 45 ° of time is rotated according to motor Determine the second revolving speed of the motor；
Described second determines that submodule is used for when the first revolving speed v meets 50rpm≤v≤180rpm, is rotated according to motor 180 ° of time determines the second revolving speed of the motor.
10. computing device according to claim 9, which is characterized in that described first determines that submodule includes the first reception Unit and the first computing unit；
First receiving unit is used to obtain motor turn signal when motor rotation based on magnetoresistive sensor, and the motor turns Dynamic signal includes sinusoidal signal and cosine signal；
First computing unit is used to determine that the motor rotates 45 ° of time Δ according to the sinusoidal signal and cosine signal T45°, using formula S pd2=1000*60* (45/360)/Δ T45°Calculate the second revolving speed of the motor；
Described second determines that submodule includes the second receiving unit and the second computing unit；
Second receiving unit is used to obtain motor turn signal when motor rotation based on magnetoresistive sensor, and the motor turns Dynamic signal includes sinusoidal signal and cosine signal；
Second computing unit be used to be determined according to the sinusoidal signal and/or cosine signal the motor rotate 180 ° when Between Δ T180°, using formula S pd2=1000*60* (180/360)/Δ T180°Calculate the second revolving speed of the motor.
Technical field
This reality inventive embodiments are related to the calculation method of automobile technical field more particularly to a kind of motor speed and calculate dress It sets.
Background technique
In electric boosted brake system, the calculating of motor speed is generally by (Δ T, unit before the deadline Ms), acquire the mechanical angle (Δ θ, unit Deg) that motor turns in the time and calculate motor speed.
Summary of the invention
The purpose of the embodiment of the present invention is to propose that a kind of motor speed calculates method and computing device, solves motor and exist In the case where the slow-speed of revolution, true problem is not calculated accurately to motor tacho.
For this purpose, in a first aspect, the embodiment of the invention provides a kind of calculation methods of motor speed, comprising:
Calculate the first revolving speed of motor；
When first revolving speed is less than preset rotation speed, the electricity is determined according to the time that motor rotates setting rotational angle Second revolving speed of machine, and using second revolving speed as the actual speed of the motor.
Optionally, when first revolving speed is less than preset rotation speed, the time for rotating setting rotational angle according to motor is true Second revolving speed of the fixed motor, comprising:
When the first revolving speed v meets v < 50rpm, the second of the motor is determined according to the time that motor rotates 45 ° Revolving speed；
When the first revolving speed v meets 50rpm≤v≤300rpm, rotated according to motor described in 180 ° of time determination Second revolving speed of motor.
Optionally, when the first revolving speed v meets v < 50rpm, the motor is determined according to the time that motor rotates 45 ° The second revolving speed, comprising:
Motor turn signal when motor rotation is obtained based on magnetoresistive sensor, the motor turn signal includes sinusoidal letter Number and cosine signal；
Determine that the motor rotates 45 ° of time Δ T according to the sinusoidal signal and cosine signal45°, using formula S pd2 =1000*60* (45/360)/Δ T45°Calculate the second revolving speed of the motor；
When the first revolving speed v meets 50rpm≤v≤300rpm, rotated according to motor described in 180 ° of time determination Second revolving speed of motor, comprising:
Motor turn signal when motor rotation is obtained based on magnetoresistive sensor, the motor turn signal includes sinusoidal letter Number and/or cosine signal；
Determine that the motor rotates 180 ° of time Δ T according to the sinusoidal signal and/or cosine signal180°, using public affairs Formula Spd2=1000*60* (180/360)/Δ T180°Calculate the second revolving speed of the motor.
Optionally, the sinusoidal signal includes the first sinusoidal signal and the second sinusoidal signal, and the cosine signal includes the One cosine signal and the second cosine signal；
Determine that the motor rotates 45 ° of time Δ T according to the sinusoidal signal and cosine signal45°, comprising:
Sine difference signal is determined according to first sinusoidal signal and the second sinusoidal signal, is believed according to first cosine Number and the second cosine signal determine cosine differential signal；
Determine that the motor rotates 45 ° of time Δ T according to the sine difference signal and the cosine differential signal45°；
Determine that the motor rotates 180 ° of time Δ T according to the sinusoidal signal and/or cosine signal180°, comprising:
Sine difference signal is determined according to first sinusoidal signal and the second sinusoidal signal, is believed according to first cosine Number and the second cosine signal determine cosine differential signal；
Determine that the motor rotates 180 ° of time Δ according to the sine difference signal and/or the cosine differential signal T180°。
Optionally, according to the sine difference signal and the cosine differential signal determine the motor rotate 45 ° when Between Δ T45°, comprising:
First time T1 is determined according to the initial time of the sine difference signal and the cosine differential signal；
The second time T2 is determined according to the sine difference signal and the cosine differential signal time equal for the first time；
45 ° of time, i.e. Δ are rotated using the difference between second time and the first time as the motor T45°=T2-T1；Alternatively,
According to the sine difference signal and the cosine differential signal, the time equal for the first time determines first time T1 '；
According to the sine difference signal and the cosine differential signal again equal time as the second time T2 '；
The time that the motor rotates 45 °, i.e. Δ are calculated with the difference between second time and the first time T45°=(T2 '-T1 ')/4；
Determine that the motor rotates 180 ° of time Δ according to the sine difference signal and the cosine differential signal T180°, comprising:
Third time T3 is determined according to the initial time of the sine difference signal；
According to the sine difference signal, the null time determines the 4th time T4 for the first time；
180 ° of time, i.e. Δ are rotated using the difference between the 4th time and the third time as the motor T180°=T4-T3；And/or
According to the cosine differential signal, the null time determines third time T3 ' for the first time；
The 4th time T4 ' is determined according to the time that the cosine differential signal is again equal to zero；
180 ° of time, i.e. Δ are rotated using the difference between the 4th time and the third time as the motor T180°=T4 '-T3 '.
Optionally, the first revolving speed of motor is calculated, comprising:
Obtain rotational angle Δ θ of the motor in certain time Δ T；
Using formula S pd1=1000*60* (Δ θ/360)/Δ T calculates the first revolving speed of the motor.
Optionally, the calculation method further include:
When first revolving speed is greater than the preset rotation speed, turn using first revolving speed as the reality of the motor Speed.
Second aspect, the embodiment of the invention also provides a kind of computing devices of motor speed, comprising:
First revolving speed computing module, for calculating the first revolving speed；
Actual speed determining module, for being turned according to motor rotation setting when first revolving speed is less than preset rotation speed The time of dynamic angle determines the second revolving speed of the motor, and using second revolving speed as the actual speed of the motor.
Optionally, the actual speed determining module includes that the first determining submodule and second determine submodule；
Described first determines that submodule is used for when the first revolving speed v meets v < 50rpm, rotates 45 ° according to motor Time determines the second revolving speed of the motor；
Described second determines that submodule is used for when the first revolving speed v meets 50rpm≤v≤180rpm, according to motor The time of 180 ° of rotation determines the second revolving speed of the motor.
Optionally, described first determine that submodule includes the first receiving unit and the first computing unit；
First receiving unit is used to obtain motor turn signal when motor rotation, the electricity based on magnetoresistive sensor Machine turn signal includes sinusoidal signal and cosine signal；
First computing unit be used to be determined according to the sinusoidal signal and cosine signal the motor rotate 45 ° when Between Δ T45°, using formula S pd2=1000*60* (45/360)/Δ T45°Calculate the second revolving speed of the motor；
Described second determines that submodule includes the second receiving unit and the second computing unit；
Second receiving unit is used to obtain motor turn signal when motor rotation, the electricity based on magnetoresistive sensor Machine turn signal includes sinusoidal signal and cosine signal；
Second computing unit is used to determine that the motor rotates 180 ° according to the sinusoidal signal and/or cosine signal Time Δ T180°, using formula S pd2=1000*60* (180/360)/Δ T180°Calculate the second revolving speed of the motor.
The calculation method and computing device of motor speed provided in an embodiment of the present invention, progress motor calculation is pre- first Estimate, obtain the first revolving speed of motor, by the way that the first revolving speed to be compared with preset tachometer value, is less than in the first revolving speed default In the case where revolving speed, the second revolving speed of the motor is determined according to the time of motor rotational angle, using the second revolving speed as motor reality The revolving speed on border.Motor is avoided in the lesser situation of revolving speed, mechanical angle is due to fluctuating the generation for leading to calculate error.Pass through benefit Motor speed is determined with the time of motor rotational angle, improves the accuracy of calculating, improves electric boosted brake gear Performance.
Detailed description of the invention
Fig. 1 is the flow chart that motor speed provided in an embodiment of the present invention calculates method.
Fig. 2 is a kind of calculation method of motor speed provided in an embodiment of the present invention.
Fig. 3 is the calculation method of another motor speed provided in an embodiment of the present invention.
Fig. 4 is sinusoidal signal provided in an embodiment of the present invention and cosine signal difference processing schematic diagram.
Fig. 5 is that another motor speed provided in an embodiment of the present invention calculates method.
Fig. 6 is the schematic diagram of the computing device of motor speed provided in an embodiment of the present invention.
Specific embodiment
The technical issues of to solve the embodiment of the present invention, the technical solution of use and the technical effect that reaches are more clear Chu, below with reference to the accompanying drawings and specific embodiments to further illustrate the technical scheme of the present invention.It is understood that this Locate described specific embodiment to be used only for explaining the present invention rather than limiting the invention.It also should be noted that For ease of description, only some but not all contents related to the present invention are shown in the drawings.
Fig. 1 is the flow chart that motor speed provided in an embodiment of the present invention calculates method, as shown in Figure 1, a kind of motor turns Speed calculation method include:
S110, the first revolving speed for calculating motor；
The revolving speed of motor is substantially estimated, for the substantially range of speeds of lock out motor, corresponding motor is different to be turned Fast range flexibly treats the calculation method under different motor speeds using different calculation methods, improves motor at the low rotational speed Calculating accuracy rate.
S120, when the first revolving speed be less than preset rotation speed when, according to motor rotate setting rotational angle time determine motor The second revolving speed, and using the second revolving speed as the actual speed of the motor.
When the first revolving speed is less than pre-set revolving speed, so that it may think that motor is run at the low rotational speed, according to motor The time of a certain angle is rotated to determine the second revolving speed of motor, and using the second revolving speed as the actual speed of motor.It avoids Motor is in the lesser situation of revolving speed, since mechanical angle fluctuation leads to the generation for calculating error.By utilizing motor rotational angle Time determine motor speed, improve the accuracy of calculating, improve the performance of electric boosted brake gear.
On the basis of the above embodiments, when the first revolving speed is less than preset rotation speed, setting angle of rotation is rotated according to motor The time of degree determines the second revolving speed of the motor, comprising:
When the first revolving speed v meets v < 50rpm, the second revolving speed of motor is determined according to the time that motor rotates 45 °；
When the first revolving speed v meets 50rpm≤v≤300rpm, that 180 ° of time determines motor is rotated according to motor Two revolving speeds.
When the first revolving speed of motor is less than 50rpm, it is determined that motor turns over 45 ° of time to determine second turn of motor Speed, when motor the first revolving speed be greater than or equal to 50rpm, be less than or equal to 300rpm when, then according to motor turn over 180 ° when Between determine motor the second revolving speed.45 ° or 180 ° of time is turned over to determine the second revolving speed of motor by acquisition motor, is avoided Because mechanical angle fluctuation leads to the generation for calculating error, calculating precision is improved.It should be noted that the embodiment of the present invention Merely exemplary property illustrates technical solution of the electrode under smaller revolving speed, can be with motor when the first revolving speed of motor is less than 50rpm 45 ° of time is turned over to determine the second revolving speed of motor, the time that any determination angle can also be turned over by motor determines electricity Second revolving speed of machine, the embodiment of the present invention is to this without limiting；Meanwhile when the first revolving speed of motor be greater than or equal to 50rpm, When less than or equal to 300rpm, then the second revolving speed of motor is determined according to the time that motor turns over 180 °, can also pass through motor The time for turning over any determination angle determines the second revolving speed of motor, and the embodiment of the present invention is to this without limiting.
Fig. 2 is a kind of calculation method of motor speed provided in an embodiment of the present invention, as shown in Fig. 2, optionally, first When revolving speed v meets v < 50rpm, the second revolving speed of the motor is determined according to the time that motor rotates 45 °, comprising:
Based on magnetoresistive sensor obtain motor rotation when motor turn signal, motor turn signal include sinusoidal signal and Cosine signal；
Determine that the motor rotates 45 ° of time Δ T according to sinusoidal signal and cosine signal45°, using formula S pd2= 1000*60*(45/360)/ΔT45°Calculate the second revolving speed of the motor.
Fig. 3 is the calculation method of another motor speed provided in an embodiment of the present invention, as shown in figure 3, in the first revolving speed v When meeting 50rpm≤v≤300rpm, the second revolving speed of the motor is determined according to the time that motor rotates 180 °, comprising:
Motor turn signal when motor rotation is obtained based on magnetoresistive sensor, motor turn signal includes sinusoidal signal And/or cosine signal；
Determine that the motor rotates 180 ° of time Δ T according to the sinusoidal signal and/or cosine signal180°, using public affairs Formula Spd2=1000*60* (180/360)/Δ T180°Calculate the second revolving speed of the motor.
When the first revolving speed meets v < 50rpm, motor when motor rotates is obtained using magnetoresistive sensor and rotates sinusoidal letter Number and cosine signal, time used when determining that motor rotates 45 ° by sinusoidal signal and cosine signal, to utilize formula meter Calculate motor revolving speed, when the first revolving speed meets 50rpm≤v≤300rpm, since revolving speed is slightly larger, motor turn over 45 ° when institute Time can be shorter, it is not easy to it captures, so acquisition motor time used when turning over 180 ° calculates the revolving speed of motor, Improve the precision that motor calculates motor speed in the case where low-speed running.
On the basis of the above embodiments, Fig. 4 is at sinusoidal signal provided in an embodiment of the present invention and cosine signal difference Schematic diagram is managed, as shown in figure 4, optionally, sinusoidal signal includes the first sinusoidal signal and the second sinusoidal signal, cosine signal include First cosine signal and the second cosine signal；
Determine that motor rotates 45 ° of time Δ T according to sinusoidal signal and cosine signal45°, comprising:
Sine difference signal is determined according to the first sinusoidal signal and the second sinusoidal signal, according to the first cosine signal and second Cosine signal determines cosine differential signal；
Determine that motor rotates 45 ° of time Δ T according to sine difference signal and cosine differential signal45°；
Determine that motor rotates 180 ° of time Δ T according to sinusoidal signal and/or cosine signal180°, comprising:
Sine difference signal is determined according to the first sinusoidal signal and the second sinusoidal signal, according to the first cosine signal and second Cosine signal determines cosine differential signal；
Determine that the motor rotates 180 ° of time Δ T according to sine difference signal and/or cosine differential signal180°。
The first sinusoidal signal, the second sinusoidal signal, the first cosine signal and the when magnetoresistive sensor obtains motor rotation First sinusoidal signal and the second sinusoidal signal are passed through difference processing, sine difference signal are obtained, by more than first by two cosine signals String signal and the second cosine signal pass through difference processing, obtain cosine differential signal, utilize sine difference signal and cosine difference Signal determines that motor rotates 45 ° of time Δ T45°, guarantee that motor rotates 45 ° of time accurate and effective, using sinusoidal sub-signal and Cosine differential signal determines that motor rotates 180 ° of time Δ T180°, guarantee that motor rotates 180 ° of time accurate and effective.
On the basis of the above embodiments, determine that motor rotates 45 ° according to sine difference signal and cosine differential signal Time Δ T45°, comprising:
First time T1 is determined according to the initial time of sine difference signal and the cosine differential signal；
The second time T2 is determined according to sine difference signal and the cosine differential signal time equal for the first time；
45 ° of time, i.e. Δ T are rotated using the difference between the second time and first time as the motor45°=T2- T1；Alternatively,
First time T1 ' is determined according to sine difference signal and the cosine differential signal time equal for the first time；
According to sine difference signal and cosine differential signal again equal time as the second time T2 '；
The time that the motor rotates 45 °, i.e. Δ T are calculated with the difference between the second time and first time45°= (T2'-T1')/4；
Determine that motor rotates 180 ° of time Δ T according to sine difference signal and cosine differential signal180°, comprising:
Third time T3 is determined according to the initial time of sine difference signal；
According to sine difference signal, the null time determines the 4th time T4 for the first time；
180 ° of time, i.e. Δ T are rotated using the difference between the 4th time and third time as the motor180°= T4-T3；And/or
According to cosine differential signal, the null time determines third time T3 ' for the first time；
The 4th time T4 ' is determined according to the time that cosine differential signal is again equal to zero；
180 ° of time, i.e. Δ T are rotated using the difference between the 4th time and the third time as the motor180° =T4 '-T3 '.
Since functional value is equal 45 degree at the time of for SIN function and cosine function, so working as sine difference signal and cosine When motor output valve corresponding to differential signal is equal for the first time, just illustrate that motor has turned over 45 degree, so from differential signal The time of beginning is counted, and the time equal for the first time to sine difference signal and cosine differential signal turns over used in 45 degree as motor Time.Alternatively, due to the periodicity of sine and cosine, to sinusoidal poor at the time of sine difference signal and cosine differential signal equal for the first time At the time of sub-signal is equal with second of cosine differential signal, 4 times of motors of just having passed by turn over 45 degree of time, so as to Determine motor turn over 45 degree used in the time.
Due to the characteristic of SIN function and cosine function, the time originated from differential signal is counted, and arrives sine difference signal The null time is the time that motor turns over 180 degree for the first time.And/or from cosine differential signal null time for the first time It counts, the time for being again equal to zero to cosine differential signal is the time that motor turns over 180 degree.By the determination of above-mentioned time, Using the feature of sine difference signal and cosine differential signal, the angle that accurate control motor turns over reduces error formation Possibility more accurately calculates the revolving speed of motor.
In conclusion the calculation method of motor speed provided in an embodiment of the present invention, in the lesser situation of motor speed, The actual speed of the motor is determined according to the time of motor rotational angle.Motor is avoided in the lesser situation of revolving speed, by Lead to the generation for calculating error in mechanical angle fluctuation.Motor speed is determined by the time using motor rotational angle, is improved The accuracy calculated, improves the performance of electric boosted brake gear.
On the basis of the above embodiments, Fig. 5 is that another motor speed provided in an embodiment of the present invention calculates method, figure 5 motor speed, which calculates method, can be adapted for the larger situation of motor speed.As shown in figure 5, optionally, calculating the of motor One revolving speed, comprising:
Obtain rotational angle Δ θ of the motor in certain time Δ T；
Using formula S pd1=1000*60* (Δ θ/360)/Δ T calculates the first revolving speed of motor.
First revolving speed of motor is calculated by the angle that motor in acquisition a period of time turns over, and which is at motor It is calculated in high-revolving situation relatively precisely, but it is first the motor slow-speed of revolution the case where, since motor turns over mechanical angle low It is easy to happen fluctuation under speed conditions, causes mechanical angle angle calculation inaccurate, to influence the accuracy of motor speed.Example Property, θ can be acquired1To θ2Between motor the time Δ T, Δ θ=θ that turn over2-θ1, so that the first revolving speed of motor is calculated, First revolving speed is compared with preset value, the case where whether motor is in the slow-speed of revolution determined, so that adaptability takes difference Mode calculates motor speed, and guarantee accurately calculates the revolving speed of motor.
Optionally, calculation method further include:
When the first revolving speed is greater than the preset rotation speed, using the first revolving speed as the actual speed of motor.
When the first revolving speed of motor is greater than preset value, it can determine that motor is running at high speed, since motor is running at high speed In the case where, mechanical angle is not susceptible to fluctuate, so the first revolving speed can represent the reality of motor in the case where running at high speed Revolving speed.The process of motor speed calculating is saved, and ensure that the accuracy that motor speed calculates.
Based on same inventive concept, the embodiment of the invention also provides a kind of computing device of motor speed, Fig. 6 is this The computing device schematic diagram for the motor speed that inventive embodiments provide, as shown in fig. 6, the computing device of motor speed can wrap It includes:
First revolving speed computing module 1, for calculating the first revolving speed；
Actual speed determining module 2, for rotating setting angle of rotation according to motor when the first revolving speed is less than preset rotation speed The time of degree determines the second revolving speed of motor, and using the second revolving speed as the actual speed of the motor.
Optionally, actual speed determining module 2 may include that the first determining submodule 3 and second determines submodule 4；
First determines that submodule 3 is used for when the first revolving speed v meets v < 50rpm, and 45 ° of time is rotated according to motor Determine the second revolving speed of the motor；
Second determines that submodule 4 is used for when the first revolving speed v meets 50rpm≤v≤180rpm, is rotated according to motor 180 ° of time determines the second revolving speed of the motor.
When the first revolving speed v meets v < 50rpm, first determines that submodule 3 rotates 45 degree of time using motor to determine Second revolving speed of motor, since motor speed is lower, the time that acquisition motor rotates 45 degree facilitates calculating process.At first turn When fast v meets 50rpm≤v≤180rpm, since motor speed is very fast, the time of 45 degree of acquisition is less susceptible to, so acquisition electricity The time of machine rotation 180 degree calculates the second revolving speed of motor, ensure that the precision that motor speed calculates.
Optionally, first determine that submodule 3 may include the first receiving unit 5 and the first computing unit 6；
First receiving unit 5 is used to obtain motor turn signal when motor rotation, motor rotation based on magnetoresistive sensor Signal includes sinusoidal signal and cosine signal；
First computing unit 6 is used to determine that the motor rotates 45 ° of time Δ according to sinusoidal signal and cosine signal T45°, using formula S pd2=1000*60* (45/360)/Δ T45°Calculate the second revolving speed of motor；
Second determines that submodule 4 includes the second receiving unit 7 and the second computing unit 8；
Second receiving unit 7 is used to obtain motor turn signal when motor rotation, motor rotation based on magnetoresistive sensor Signal includes sinusoidal signal and cosine signal；
Second computing unit 8 is used to determine that the motor rotates 180 ° of time according to sinusoidal signal and/or cosine signal ΔT180°, using formula S pd2=1000*60* (180/360)/Δ T180°Calculate the second revolving speed of motor.
Optionally, sinusoidal signal includes the first sinusoidal signal and the second sinusoidal signal, and cosine signal is believed including the first cosine Number and the second cosine signal；First computing unit 6 includes that the first differential signal determines subelement 61 and determines that son is single at the first time Member 62；First differential signal determines subelement 61 for determining that sine difference is believed according to the first sinusoidal signal and the second sinusoidal signal Number, cosine differential signal is determined according to the first cosine signal and the second cosine signal；Determine that subelement 62 is used for root at the first time Determine that motor rotates 45 ° of time Δ T according to sine difference signal and cosine differential signal45°；Second computing unit 8 includes second Differential signal determines that subelement 81 and the second time determine subelement 82；Second differential signal determines subelement 81 for according to the One sinusoidal signal and the second sinusoidal signal determine sine difference signal, more than the first cosine signal and the determination of the second cosine signal String differential signal；Second time determined subelement 82 for determining motor according to sine difference signal and/or cosine differential signal The time Δ T of 180 ° of rotation180°。
Determine that subelement 61 forms sine difference signal and cosine differential signal by the first differential signal, at the first time really Stator unit 62 determines that motor rotates 45 degree of times used using sine difference signal and cosine differential signal；It is poor by second Sub-signal determines that subelement 81 forms sine difference signal and cosine differential signal, and the second time determined subelement 82 using sine Differential signal and/or cosine differential signal determine the time used in motor rotation 180 degree, turn over 45 by being accurately obtained motor Degree or 180 time, the revolving speed of accurate calculation motor, improve motor speed calculating precision.
Optionally, determine that subelement 62 is specifically used for according to sine difference signal and cosine differential signal at the first time Time beginning determines first time T1；Determined for the second time according to sine difference signal and the cosine differential signal time equal for the first time T2；45 ° of time, i.e. ,=T2-T1 are rotated using the difference between the second time and first time as the motor；Or first Time determines that subelement 62 is specifically used for determining first according to sine difference signal and the cosine differential signal time equal for the first time Time T1 '；According to sine difference signal and cosine differential signal again equal time as the second time T2 '；When with second Between difference between first time calculate the time that the motor rotates 45 °, i.e. ,=(T2 '-T1 ')/4；Second time determined Subelement 82 is specifically used for determining third time T3 according to the initial time of sine difference signal；For the first time according to sine difference signal The null time determines the 4th time T4；Using the difference between the 4th time and third time as motor rotate 180 ° when Between, i.e. Δ T180°=T4-T3；And/or second the time determine that subelement is specifically used for according to cosine differential signal being equal to zero for the first time Time determine third time T3 '；The 4th time T4 ' is determined according to the time that cosine differential signal is again equal to zero；With the 4th Difference between time and the third time rotates 180 ° of time, i.e. Δ T as motor180°=T4 '-T3 '.
By the calculating of the first revolving speed to motor, the actual speed of motor is estimated, when motor speed is less than preset rotation speed When, judge that motor is in low speed operation, turns over the time of 45 degree or 180 degree using motor to determine the second revolving speed of motor, and Using the second revolving speed as the actual speed of motor, reduce motor low speed operation in, as mechanical angle fluctuation and caused by motor Revolving speed calculates error.
Optionally, the first revolving speed computing module 1 may include rotational angle acquisition submodule 9 and the first tachometer operator mould Block 10；Rotational angle acquisition submodule 9 is for obtaining rotational angle Δ θ of the motor in certain time Δ T；First revolving speed calculates Submodule 10 is used to use formula S pd1=1000*60* (Δ θ/360)/Δ T calculates the first revolving speed of the motor.
The rotational angle of motor within a certain period of time is obtained by rotational angle acquisition submodule 9, and utilizes the first revolving speed Computational submodule 10 calculates the first revolving speed, predefines the range of speeds of motor, judges whether motor is in slow-speed of revolution situation Under.Actual speed determining module be used for the first revolving speed be less than preset rotation speed when, using motor rotation set angle time come It determines the second revolving speed of motor, and the second revolving speed is determined as to the actual speed of motor；When the first revolving speed is greater than preset rotation speed, with Actual speed of first revolving speed as the motor.The precision for improving motor speed calculating reduces motor and transports in low speed Turn in the case where, collection machinery angle as fluctuation caused by error.
Note that the above is only a better embodiment of the present invention and the applied technical principle.It will be appreciated by those skilled in the art that The invention is not limited to the specific embodiments described herein, be able to carry out for a person skilled in the art it is various it is apparent variation, It readjusts, be combined with each other and substitutes without departing from protection scope of the present invention.Therefore, although by above embodiments to this Invention is described in further detail, but the present invention is not limited to the above embodiments only, is not departing from present inventive concept In the case of, it can also include more other equivalent embodiments, and the scope of the invention is determined by the scope of the appended claims.