CN111077357A - Current measuring device and method for motor control system and motor - Google Patents
Current measuring device and method for motor control system and motor Download PDFInfo
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- CN111077357A CN111077357A CN201911305614.XA CN201911305614A CN111077357A CN 111077357 A CN111077357 A CN 111077357A CN 201911305614 A CN201911305614 A CN 201911305614A CN 111077357 A CN111077357 A CN 111077357A
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- 238000000034 method Methods 0.000 title claims abstract description 13
- 238000004804 winding Methods 0.000 claims abstract description 60
- 238000012937 correction Methods 0.000 claims abstract description 6
- 238000012545 processing Methods 0.000 claims abstract description 4
- 238000005259 measurement Methods 0.000 claims description 13
- 230000001965 increasing effect Effects 0.000 description 6
- 238000013461 design Methods 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 230000020169 heat generation Effects 0.000 description 4
- 230000001939 inductive effect Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000001360 synchronised effect Effects 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/0092—Arrangements for measuring currents or voltages or for indicating presence or sign thereof measuring current only
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
- G01R15/14—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks
- G01R15/146—Measuring arrangements for current not covered by other subgroups of G01R15/14, e.g. using current dividers, shunts, or measuring a voltage drop
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
- G01R15/14—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks
- G01R15/20—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using galvano-magnetic devices, e.g. Hall-effect devices, i.e. measuring a magnetic field via the interaction between a current and a magnetic field, e.g. magneto resistive or Hall effect devices
- G01R15/202—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using galvano-magnetic devices, e.g. Hall-effect devices, i.e. measuring a magnetic field via the interaction between a current and a magnetic field, e.g. magneto resistive or Hall effect devices using Hall-effect devices
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Control Of Ac Motors In General (AREA)
Abstract
The invention provides a current measuring device and a method for a motor control system, which are used for measuring the current in the motor control system, wherein the motor is a single-phase, three-phase or multi-phase winding motor, and each phase winding comprises N parallel windings; the current measuring device comprises N current sensors corresponding to each phase winding of the motor, wherein N is more than or equal to 1 and less than N/2, and a single current sensor is used for measuring the current of any branch in N parallel windings; the current measuring device also comprises a signal processing module which is used for receiving the current signal { I detected by the current sensor1，I2，…InAnd calculating to obtain the current I of each phase windingR＝βN(I1+I2+…+In) N, wherein β is a correction factor, and the total current of the motorThe scheme solves the limitation problem that a small current measuring element is used for measuring large current in parallel in a motor control system.
Description
Technical Field
The invention relates to the field of motor equipment, in particular to a current measuring device and method for a motor control system and a motor with the current measuring device.
Background
In many integrated circuits, real-time observation of the current of each powered link is usually required. The measurement of the current is dependent on the current sensor. The current sensors are different in variety according to measurement principles, and can be mainly divided into: shunts, electromagnetic current transformers, electronic current transformers, and the like.
Taking a three-phase permanent magnet synchronous motor as an example, in a three-phase permanent magnet synchronous motor control system, the magnitude of input current (ac/dc) and the output current (ac) of each phase need to be observed simultaneously, so as to ensure the open-close loop control and state monitoring of the motor. In the existing technical scheme, the type of a current sensor is selected according to the current of each circuit, and one sensor corresponds to one circuit to observe. For example: the maximum current for the design of line 1 is 10 amps, then current observation would be a reasonable choice for current sensors using a range of 10 amps or more. In motor control systems, most of the existing solutions use a relatively inexpensive resistance current instead of a current sensor under low current demand, and use a hall current sensor under high current.
Because the working ranges of various current sensor components and the respective advantages and disadvantages are different, under many working conditions, the type selection of the current sensor will restrict the design and development of the control system, such as: cost, volume, weight, heat generation, etc.
For example, a hall sensor is compared with a resistive sensor. When measuring large current, the Hall sensor has the characteristics of low heat generation, large measuring range, high precision and the like. But in the middle and small measuring range links, the resistance sensor can also show the characteristics of low cost, small volume and other commercial convenience.
As shown in fig. 1(a) and (b), when measuring a large current, some designs also adopt a form of connecting multiple groups of resistance-type sensors in parallel, so that a single-phase large current is successfully shunted to each phase of current, thereby satisfying the range requirement of the resistance-type sensors and replacing the hall sensors. However, with this design, the number of sensors is increased, and the cost cannot be reduced excessively. Meanwhile, the difficulty of arranging the wiring of the components is increased due to the distributed sensor layout, so that the overall size is increased.
In the current measurementWhen the current is increased, the Hall sensor is expensive, the volume is greatly increased compared with the resistance sensor, but under the condition of large current, the resistance sensor which is connected in parallel too much is connected into a circuit in series according to the P-I2The R formula indicates that each resistor causes a serious heat generation problem.
Disclosure of Invention
The invention aims to provide a current measuring device and a current measuring method for a motor control system, which aim to solve the problem of limitation of measuring large current in parallel by using a small current measuring element in the motor control system.
A first object of the present invention is to provide a current measuring device for use in a motor control system, the motor being a single-phase, three-phase or multi-phase winding motor, each phase winding comprising N parallel windings; the current measuring device comprises N current sensors corresponding to each phase winding of the motor, wherein N is more than or equal to 1 and less than N/2, and a single current sensor is used for measuring the current of any branch in N parallel windings; the current measuring device comprises a signal processing module, wherein the signal processing module is used for receiving a current signal { I ] detected by the current sensor1，I2，…InAnd calculating to obtain the current I of each phase windingR＝βN(I1+I2+…+In) And/n, wherein β is a correction factor and the total current of the motor.
Optionally, the current sensor is a non-contact sensor, including but not limited to a hall sensor.
Optionally, the current sensor is an access current sensor, including but not limited to a resistive current sensor.
Optionally, the motor is a dc motor or an ac motor.
Preferably, the current sensors corresponding to each phase winding of the motor are configured to be n-1.
A second object of the present invention is to provide a current measuring method for use in a motor control system, the motor being a single-phase, three-phase or multi-phase winding motor, each phase winding including N parallel windings, the method comprising the steps of:
s1, measuring N branch currents in the N parallel windings by using a current sensor, wherein N is more than or equal to 1 and is less than N/2;
s2, obtaining the current I of each phase winding of the motor according to the measurement result of the current sensorR＝βN(I1+I2+…+In) And/n, wherein β is a correction factor and the total current of the motor.
Further, in step S1, N is equal to 1, and the current sensor is used to measure the current of a single branch in the N parallel windings.
A third object of the present invention is to provide an electric machine, which is a single-phase, three-phase or multi-phase winding electric machine, each phase winding comprising N parallel windings, the control system of the electric machine being configured with a current measuring device according to the first object of the present invention.
The invention has the following beneficial technical effects:
the scheme of the invention can replace the existing mode of measuring the large current by adopting a Hall sensor or connecting a plurality of groups of resistance sensors in parallel, and the small current measuring element is used in the motor control system to measure the large current in parallel, thereby reducing the use cost and the use number of the current sensor, reducing the loss and the heat brought by the current sensor, and on the other hand, increasing the possibility of circuit design to meet the requirements of special occasions.
Drawings
Fig. 1 is a schematic diagram of two conventional modes for measuring a large current.
Fig. 2 is a schematic diagram of a conventional measurement scheme and a new architecture scheme for branch current measurement.
Fig. 3 is a schematic diagram of a conventional three-phase motor current measuring method.
Fig. 4 is a schematic diagram of a current measuring method of a three-phase motor according to an embodiment of the present invention.
Detailed Description
For a further understanding of the invention, reference will now be made to the preferred embodiments of the invention by way of example, and it is to be understood that the description is intended to further illustrate features and advantages of the invention, and not to limit the scope of the claims.
Aiming at the problems of large number of required components, high wiring difficulty, serious heat generation and the like in the current measurement mode of the traditional parallel multi-group resistance type sensor shown in fig. 2(a), the invention provides a new architecture scheme shown in fig. 2 (b). On the basis of the original framework, the new scheme is that the current sensors 2-N are removed, the current sensors 1 are reserved, and the magnitude of each branch current is calculated through the relation among the branch currents and based on the measurement result of the branch current 1, so that the magnitude of the total current is calculated.
If the current sensor adopts a non-contact sensor, such as a Hall sensor, under the ideal condition, the architecture of the new scheme can be directly used. However, in practical applications, the branch current is a pure wire, and the uncertainty of the welding point can generate unbalanced distribution of resistance and inductance, thereby affecting the current estimation accuracy. If an access sensor, such as a resistive current sensor, is used, the resistance value of the measurement branch is much larger than the branch current due to the resistance and inductance of the access device, and thus the estimation result is invalid. Therefore, the architecture of the new scheme cannot be directly used for measurement in the circuit regardless of the measurement mode.
In conventional motor control (here, a three-phase star-connected motor winding is taken as an example), as shown in fig. 3, a measurement circuit is directly connected to a winding of a UVW phase of a motor, and a motor winding is the largest resistance and inductive load in the whole circuit, and the magnitude of the resistance and the inductive load is far higher than the resistance value of a resistance sensor or unstable resistance caused by welding points in the circuit.
Thus the parallel nature of the parallel-wound branches of the motor windings in current can be exploited by splitting the parallel-wound windings 1-N in each phase of the UVW into parallel current groups 1-N, with the winding 1 (or more windings) in each phase of the UVW connected to the current sensor. Because the resistance value of the motor winding is far larger than the extra resistance generated by the current sensor, the influence of the resistance value on the current detection can be ignored.
Based on the above description of the principles, embodiments of the present invention provide a current measurement apparatus and method for use in a motor control system.
As shown in fig. 4, again taking the star connection winding of the three-phase motor as an example, each phase winding of the star connection winding comprises N parallel windings, and parallel current groups 1-N are formed. A current sensor is connected to winding 1 (or more windings N, 1. ltoreq. N < N/2) in each phase of UVW to measure the current in winding 1 (or N windings). Furthermore, the current of each phase of UVW can be deduced from the measured current in winding 1 (or n windings) based on the parallel nature of the parallel winding branches in current. The current of each phase can be specifically calculated by the following formula:
IR＝βN(I1+I2+…+In)/n
wherein β is a correction factor when only the current I in winding 1 is measured1Time phase current IR＝βNI1。
And then, obtaining the total current according to the measured current of each phase of UVW.
When the measuring framework is adopted, the current sensor can be a non-contact sensor, such as a Hall sensor; or an access current sensor, such as a resistive current sensor.
The motor suitable for the motor can be a single-phase, three-phase or multi-phase winding motor with a parallel winding, and can be a direct current motor or an alternating current motor.
The above description of the embodiments is only intended to facilitate the understanding of the method of the invention and its core idea. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.
Claims (8)
1. A current measuring device for use in a motor control system, the motor being a single phase, three phase or multi-phase winding motor, each phase winding comprising N parallel windings, wherein: the current measuring device comprises N current sensors corresponding to each phase winding of the motor, wherein N is more than or equal to 1 and less than N/2, and a single current sensor is used for measuring the current of any branch in N parallel windings; the current measuring device further comprises a signalA processing module for receiving the current signal { I ] detected by the current sensor1，I2，…InAnd calculating to obtain the current I of each phase windingR＝βN(I1+I2+…+In) And/n, wherein β is a correction factor and the total current of the motor.
2. A current measuring device for use in a motor control system according to claim 1, wherein: the current sensor is a non-contact sensor, including but not limited to a hall sensor.
3. A current measuring device for use in a motor control system according to claim 1, wherein: the current sensor is an on-type current sensor, including but not limited to a resistive current sensor.
4. A current measuring device for use in a motor control system according to claim 1, wherein: the motor is a direct current motor or an alternating current motor.
5. The current measuring apparatus for use in a motor control system according to any one of claims 1 to 4, wherein: the current sensors corresponding to each phase winding of the motor are configured to be n-1.
6. A current measuring method for use in a motor control system, said motor being a single phase, three phase or multi-phase winding motor, each phase winding comprising N parallel windings, comprising the steps of:
s1, measuring N branch currents in the N parallel windings by using a current sensor, wherein N is more than or equal to 1 and is less than N/2;
s2, obtaining the current I of each phase winding of the motor according to the measurement result of the current sensorR＝βN(I1+I2+…+In) And/n, wherein β is a correction factor and the total current of the motor.
7. The current measuring method for use in a motor control system according to claim 6, wherein in step S1, N is 1, and a single branch current in N parallel windings is measured using a current sensor.
8. An electric machine, which is a single-phase, three-phase or multi-phase winding machine, each phase winding comprising N parallel windings, characterized in that the control system of the machine is provided with a current measuring device according to any of claims 1-5.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201911305614.XA CN111077357A (en) | 2019-12-17 | 2019-12-17 | Current measuring device and method for motor control system and motor |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911305614.XA CN111077357A (en) | 2019-12-17 | 2019-12-17 | Current measuring device and method for motor control system and motor |
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| CN111077357A true CN111077357A (en) | 2020-04-28 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113884741A (en) * | 2021-09-09 | 2022-01-04 | 广东福德电子有限公司 | Large current detection sensor |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6528960B1 (en) * | 2000-11-08 | 2003-03-04 | Bae Systems Controls, Inc. | Cost effective measurement of high currents |
| US20040239335A1 (en) * | 2003-05-29 | 2004-12-02 | Switched Reluctance Drives Limited | Current measurement in electrical machines |
| CN105453413A (en) * | 2013-08-15 | 2016-03-30 | 罗伯特·博世有限公司 | Method and device for determining phase currents and an excitation current of an electrical machine, and motor system |
| CN211826208U (en) * | 2019-12-17 | 2020-10-30 | 埃威(杭州)科技有限责任公司 | Current measuring device for motor control system and motor |
-
2019
- 2019-12-17 CN CN201911305614.XA patent/CN111077357A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6528960B1 (en) * | 2000-11-08 | 2003-03-04 | Bae Systems Controls, Inc. | Cost effective measurement of high currents |
| US20040239335A1 (en) * | 2003-05-29 | 2004-12-02 | Switched Reluctance Drives Limited | Current measurement in electrical machines |
| CN105453413A (en) * | 2013-08-15 | 2016-03-30 | 罗伯特·博世有限公司 | Method and device for determining phase currents and an excitation current of an electrical machine, and motor system |
| CN211826208U (en) * | 2019-12-17 | 2020-10-30 | 埃威(杭州)科技有限责任公司 | Current measuring device for motor control system and motor |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113884741A (en) * | 2021-09-09 | 2022-01-04 | 广东福德电子有限公司 | Large current detection sensor |
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Effective date of registration: 20220105 Address after: 310012 No. 23, Xixi villa, Xihu District, Hangzhou City, Zhejiang Province Applicant after: Shi Bowen Address before: 311121 room 406A, building 5, No. 998, Wenyi West Road, Wuchang Street, Yuhang District, Hangzhou City, Zhejiang Province Applicant before: Everway (Hangzhou) Technology Co.,Ltd. |