TW201425947A - Motor monitoring system and current detecting device thereof - Google Patents

Abstract

An embodiment of the present invention discloses a motor monitoring system and a current detecting device thereof. The current detecting device includes a current capturing module, a calculating module, and a control module. The current capturing module detects the operation current of an electrical device, and outputs a current measuring signal. The calculating module adjusts the current measuring signal and provides a first adjusted current signal according to an offset parameter and a scale parameter outputted from the control module. The offset parameter and the scale parameter are calculated by the control module in a calibration process. Therefore, the present invention can reduce the heat which is generated during large-scale current detecting process.

Description

Motor monitoring system and current detecting device

The present invention relates to a motor monitoring system and a current detecting device thereof, and more particularly to a motor monitoring system and a current detecting device thereof that can accurately estimate an operating current of a motor.

In general, a motor is an electronic device that converts electrical energy into mechanical energy to drive other devices. In order to achieve a variety of precision operations or in order to adapt to various operating environments, the output power or speed of the motor often needs to be accurately controlled, and adjusting the drive current of the motor is a common means. However, before adjusting the drive current of the motor, it is first necessary to confirm the actual current value of the drive current in the motor to avoid errors in subsequent operations.

Traditionally, the actual current value of the drive current is often measured by a Hall sensor, but when the drive current in the motor is high, such as in an electric vehicle or other large mechanical equipment, it needs to be larger. The Hall sensor can effectively measure the drive current, which increases the manufacturing cost. At the same time, in the case of large driving current, if the resistance value or impedance value of the measuring device is high, a large amount of energy will be consumed through heat energy or other forms, which is not only too wasteful of energy, but also the operation of the motor may be safe. Doubt.

Accordingly, the industry needs a small-volume, low-cost motor monitoring system and its current sensing device to improve the conventional Hall sensor. Therefore, when applied to a lithium battery, a lead acid battery or other suitable power supply device, the motor monitoring system and its current detecting device can be simple and accurate The actual current value of the large drive current is surely detected, and a large amount of energy can be prevented from being dissipated through heat or other forms.

In view of this, the present invention provides a current detecting device that can calibrate the detected current value and reduce the inaccuracy of the detected current value due to component errors at the factory. Moreover, the current detecting device can detect a large driving current, and can avoid a large amount of energy being consumed by heat energy or other forms.

The embodiment of the invention provides a current detecting device, which includes a current capturing module to be tested, an operation module and a control module. The current sampling module to be tested detects an operating current in the electronic device, and outputs a current signal to be measured according to the current. The computing module adjusts the current signal to be tested according to at least the offset parameter and the magnification parameter to generate a first modified current signal. The control module provides an offset parameter and a magnification parameter. The control module calculates the offset parameter and the magnification parameter by a calibration procedure.

In an exemplary embodiment of the present invention, when the control module performs the calibration procedure, the electronic device fixes the operating current to at least one preset current value, and the current sampling module to be tested outputs the calibration current according to the preset current value. The signal, the operation module adjusts the calibration current signal to generate a second correction current signal, and the control module compares the actual current value and the preset current value indicated by the second correction current signal, thereby calculating the offset parameter and the magnification parameter.

In another exemplary embodiment of the present invention, the current extraction module to be tested includes a copper plate, and the copper plate is coupled to the electronic device, and the current to be tested is captured. The group detects the voltage difference generated by the working current flowing through the copper plate, and outputs the current signal to be tested according to the voltage difference. In addition, the electronic device coupled to the current sampling module to be tested is a motor. When the control module performs a calibration procedure, the electronic device to which the current extraction module to be tested is coupled is a power supply.

In still another exemplary embodiment of the present invention, the control module includes an offset calibration unit and a magnification calibration unit. In the calibration procedure, the power supply fixes the operating current to a zero current value, and the current extraction module to be tested is based on zero. The current value outputs a zero current signal, and the operation module adjusts the zero current signal according to the first preset parameter and the second preset parameter to generate an equivalent zero current signal, and the offset calibration unit compares the actual indicated by the equivalent zero current signal. The magnitude of the zero current value and the zero current value are used to adjust and record the offset parameter. On the other hand, after the offset calibration unit is adjusted in the calibration procedure, the power supply further fixes the operating current to the fixed current value, and the current sampling module to be tested outputs a fixed current signal according to the fixed current value, and the operation module is based on The adjusted offset parameter and the second preset parameter adjust the fixed current signal to generate an equivalent fixed current signal, and the magnification calibration unit compares the actual fixed current value and the fixed current value indicated by the equivalent fixed current signal, To adjust and record the magnification parameter.

The invention provides a motor monitoring system capable of calibrating the detected current value and reducing the problem that the detected current value is inaccurate due to component errors at the factory. Moreover, the current detecting device can detect a large driving current, and can avoid a large amount of energy being consumed by heat energy or other forms.

Embodiments of the present invention provide a motor monitoring system including a motor and a current detecting device. The current detecting device includes a current capturing module to be tested, an operation module, and a control module. The current to be tested The group is coupled to a motor or a power supply, detects an operating current in the motor or the power supply, and outputs a current signal to be measured. The computing module is coupled to the current measuring and capturing module, and adjusts the current signal to be tested according to at least the offset parameter and the magnification parameter to generate a first modified current signal. The control module is coupled to the computing module to provide offset parameters and magnification parameters. When the control module is calibrated, the current detecting device is coupled to the power supply, and the power supply fixes the working current to at least one preset current value, and the current sampling module to be tested outputs the calibration according to the preset current value. The current signal, the operation module adjusts the calibration current signal to generate a second correction current signal, and the control module compares the actual calibration current value indicated by the second correction current signal with the preset current value, thereby calculating the offset parameter With the magnification parameter.

In summary, the motor monitoring system and the current detecting device provided by the embodiments of the present invention are small in size and simple in design, and can easily and accurately detect the operation at a large driving current without using a conventional Hall sensor. The actual current value underneath. In addition, the conventional Hall sensor needs to use a coil, and when detecting the large driving current, a large amount of thermal energy is generated, and the motor monitoring system and the current detecting device provided by the embodiments of the present invention are more effectively reduced. Energy is dissipated through heat or other forms.

The detailed description of the present invention and the accompanying drawings are to be understood by the claims The scope is subject to any restrictions.

Please refer to FIG. 1A, which illustrates an exemplary implementation of the present invention. A functional block diagram of a current detecting device. As shown in FIG. 1A, the current detecting device 1 includes a current capturing module 10 to be tested, a computing module 12, and a control module 14. The current sampling module 10 to be tested has at least two connection terminals A and A. The other electronic device 16 can be coupled to the current extraction module 10 to be tested by the connection terminals A and A'. In addition, the current sampling module 10 and the control module 14 are respectively coupled to the computing module 12, and the computing module 12 can calculate the current sampling module 10 to be tested according to the control of the control module 14. The current level of the working current.

The connection end points A and A′ of the current sampling module 10 to be tested are coupled to the current path of the working current in the electronic device 16 , so the current extraction module 10 to be tested can be outputted according to the magnitude of the working current. Measuring the current signal. In practice, the current draw module 10 to be tested equivalently has a sufficiently precise resistance value between the two connection terminals A, A', and the resistance value can be selected in advance. When the connection terminals A and A' are coupled to the electronic device 16, the operating current of the electronic device 16 flows through the current-capturing module 10 to generate a voltage difference, and the current-capture module 10 to be tested can be based on The voltage difference outputs a current signal to be measured. In order to make the current-sampling module 10 to be tested according to the present invention more clear to those skilled in the art, an embodiment of the current-capturing module 10 to be tested is specifically described below, but the invention is not limited thereto. .

Please refer to FIG. 1A and FIG. 1B together. FIG. 1B is a functional block diagram of a current extraction module to be tested according to an exemplary embodiment of the invention. As shown in FIG. 1B, the current extraction module 10 to be tested may have a fixed resistance element 102 and a signal generating element 104. The two ends of the fixed resistance element 102 are respectively two connection terminals A, A', and the fixed resistance element 102. The current path is coupled to the operating current in the electronic device 16. Signal generating component The two ends of the fixed resistance element 102 are coupled to the two connection terminals A, A' as viewed from the circuit. Here, the signal generating component 104 is configured to detect a voltage difference between the connection terminals A, A', and output a current signal to be tested according to the voltage difference, and the connection terminal B is coupled to the operation module 12. Preferably, the signal generating component 104 can filter and amplify the voltage difference, and then output the current signal to be tested from the connection terminal B.

In practice, the resistance value of the fixed resistance element 102 can be precisely calibrated first, and the resistance value of the fixed resistance element 102 can be recorded in advance and stored in a suitable storage medium, while the operating current flow in the electronic device 16 Through the fixed resistive element 102, both ends of the fixed resistive element 102 have a voltage difference proportional to the value of the operating current. For example, the constant resistance element 102 may be a piece of metal plate. For better conductivity or cost considerations, a copper plate may be used, but not limited to a copper plate. The sheet metal is coupled to the external electronic device 16 via two connection terminals A, A'. Further, the signal generating element 104 can be assembled by the operational amplifier OP, the resistors R1, R2, and the capacitor C1. Thereby, the output terminal B of the signal generating component 104 can output the filtered and amplified voltage difference, that is, output the current signal to be tested to the computing module 12.

It should be noted that those skilled in the art can understand from FIG. 1B that the operational amplifier OP and the resistors R1 and R2 are used to amplify the voltage difference between the fixed resistance elements 102. The capacitor C1 has a filtering function. It is also possible to selectively replace other electronic circuit components that produce the same functions and effects as needed. In addition, the connection terminal B of the signal generating component 104 can also pass through The isolation unit (not shown) is coupled to the computing module 12, so that the reference grounds of the current capturing module 10 and the computing module 12 can be independent of each other, so that the current sampling module 10 is to be tested. In the case of carrying a large current, it still does not affect or interfere with the normal use of the computing module 12. In other words, the current draw module 10 to be tested can operate in a high voltage (eg, hundreds of volts) environment, and the computing module 12 can operate in a low voltage (eg, a few volts or tens of volts) environment.

Referring to FIG. 1A , the computing module 12 is coupled to the current measuring module 10 and the control module 14 , and is adjusted according to at least an offset parameter and a scale parameter provided by the control module 14 . The current signal is measured to generate a first corrected current signal. In practice, since the current signal to be tested is used to indicate the operating current in the electronic device 16, it may be indicated by the current signal to be tested due to a slight error in each component at the time of shipment or due to unstable quality during assembly. The operating current is not necessarily accurate. Therefore, the computing module 12 needs to properly calibrate the current signal to be tested, so that the calibrated current signal to be tested (ie, the aforementioned first modified current signal) can indicate the most accurate working current value.

In a practical example, the control module 14 is used to determine the degree of error of the measured operating current, and to provide appropriate offset parameters and magnification parameters to the computing module 12, and to allow the computing module 12 to be based on the offset parameters. The two parameters with the magnification parameter correct the current signal to be measured. Accordingly, how to store the most appropriate offset parameter and magnification parameter calibration in the control module 14 at a preliminary stage (for example, at the time of shipment, before sale, or before use) is a very critical issue.

This embodiment will demonstrate a calibration procedure to make the control module 14 The offset parameter and the magnification parameter described above can be calculated by a calibration procedure. In the present embodiment, during the calibration procedure (ie, calibration of the control module 14), the electronic device 16 can fix the operating current to at least one set of preset current values, such as a zero current value or a fixed current value. The current sampling module 10 outputs a corresponding calibration current signal according to the preset current value, and the operation module 12 adjusts the calibration current signal to generate a second correction current signal, and the control module 14 compares the second correction current. The actual current value indicated by the signal and the preset current value are used to calculate an offset parameter and a magnification parameter. In detail, in the calibration procedure of the calibration control module 14, the electronic device 16 can be a power generator or other suitable electronic device to provide accurate and stable voltage and current to the current detecting device 1 . Alternatively, electronic device 16 may be a motor or may be a variety of products to be sold in a non-calibration procedure or after calibration has been completed.

Here, the calibration procedure of the calibration control module 14 can be divided into two phases. The first phase is offset calibration, which is mainly to set the operating current of the electronic device 16 to zero current to detect whether the current detecting device 1 is biased. The error is shifted, thereby adjusting the offset parameters in the control module 14. The second stage is the magnification calibration, which is mainly to set the operating current of the electronic device 16 to a fixed current to detect whether the current detecting device 1 has a magnification error, thereby adjusting the magnification parameter in the control module 14.

For details, please refer to FIG. 1A, FIG. 1B and FIG. 1C. FIG. 1C is a functional block diagram of a current detecting device according to another exemplary embodiment of the present invention. As shown in FIG. 1C, the control module 14 of the current detecting device 1 further includes an offset calibration unit 142 and a magnification calibration unit 144. As described in the previous paragraph, when performing the offset calibration in the calibration procedure, The power supply can fix the operating current to the zero current value, and the signal generating component 104 in the current drawing module 10 still measures the voltage difference from both ends of the fixed resistive component 102, and the output is based on the zero current value. The zero current signal that is reached. Then, the computing module 12 can adjust the zero current signal according to a first preset parameter and a second preset parameter to generate an equivalent zero current signal. At this time, the offset calibration unit 142 in the control module 14 compares the actual zero current value and the zero current value indicated by the equivalent zero current signal, thereby modifying the first preset parameter. And stored as an offset parameter.

In a practical example, if the power supply does not output any current (ie, the operating current is zero), theoretically, no voltage difference can be measured across the resistive element 102. However, when there is still a slight voltage difference between the two ends of the fixed resistance element 102 due to the error between the elements, the zero current signal will reflect the voltage difference caused by the error, and thus the operation module 12 The equivalent zero current signal output will also have an error. At this time, the offset calibration unit 142 compares the actual zero current value indicated by the equivalent zero current signal (ie, the amount of error when the power supply is supplied with zero current) and the value of the zero current value, if the actual zero The current value is different from the zero current value, and the offset calibration unit 142 correspondingly changes the offset parameter to eliminate the error between the equivalent zero current signal (indicating the actual zero current value) and the zero current signal (indicating the zero current value). . In practice, the offset calibration unit 142 can have a non-volatile storage medium to record the adjusted offset parameters.

After the offset calibration is performed, the power supply can fix the operating current to a preset fixed current value for the magnification calibration in the calibration procedure. The signal generating component 104 in the current drawing module 10 to be tested The voltage difference is also measured from both ends of the fixed resistance element 102, thereby outputting a fixed current signal obtained in accordance with the fixed current value. Then, the computing module 12 can adjust the fixed current signal according to the adjusted offset parameter and the foregoing second preset parameter to generate an equivalent fixed current signal. At this time, the magnification calibration unit 144 in the control module 14 compares the actual fixed current value and the fixed current value indicated by the equivalent fixed current signal, thereby modifying the second preset parameter, and Store the magnification parameter.

In a practical example, the magnification calibration unit 144 compares the actual fixed current value indicated by the equivalent fixed current signal with the magnitude of the fixed current value provided. If the actual fixed current value is different from the fixed current value provided, The magnification calibration unit 144 will correspondingly change the magnification parameter to eliminate the error between the equivalent fixed current signal (indicating the actual fixed current value) and the fixed current signal (indicating the fixed current value). In practice, the magnification calibration unit 144 can also have a non-volatile storage medium to record the adjusted magnification parameter.

When the calibration procedure of the calibration control module 14 is completed, please refer to FIG. 2. FIG. 2 is a functional block diagram of a motor monitoring system according to an exemplary embodiment of the present invention. As shown in FIG. 2 , the motor monitoring system 2 is a schematic diagram of the current detecting device 1 illustrated in FIG. 1A actually monitoring the operating current of the motor 20 after completing the calibration control module 14 . That is to say, the motor monitoring system 2 actually includes the current detecting device 1 illustrated in FIG. 1A, and a motor 20 coupled to the current measuring module 10. The current detecting device 1 shown in FIG. 2 is the same as the foregoing paragraphs, and details are not described herein. In practice, when the calibration procedure is completed, the adjusted offset parameters and the adjusted magnification parameters are calculated. After the output, if the computing module 12 receives a current signal to be tested (indicating the operating current of the motor), the computing module 12 first adjusts the addition of the current signal to be tested according to the offset parameter. To remove the offset error. Then, the computing module 12 further performs multiplication adjustment on the current signal to be tested according to the magnification parameter to remove the magnification error. In this way, after the calibration of the offset parameter and the magnification parameter are fed into the computing module 12, the computing module 12 can calculate the first modified current signal, and the first modified current signal can accurately indicate the motor. The exact value of the operating current within 20.

In other examples, the offset parameter and the magnification parameter may be further determined by the external processor to assist the control module 14 and may be set, or the offset parameter and the magnification parameter may be manually adjusted by the user using an external processor. Referring to FIG. 3, FIG. 3 is a functional block diagram of a current detecting device according to still another exemplary embodiment of the present invention. 3 is the same as FIG. 1C described above, in which the current detecting device 3 of FIG. 3 also includes a current capturing module 30 to be tested, a computing module 32, and a control module 34, and the control module 34 also includes Offset calibration unit 342 and magnification calibration unit 344. However, FIG. 3 differs from FIG. 1C described above in that the control module 34 is further coupled to an external processor 36, and the external processor 36 can be used to adjust the offset calibration unit 342 and the magnification calibration unit 344.

For example, when the offset calibration is performed, the equivalent zero current signal generated by the computing module 32 is not directly fed into the control module 34, but is first fed into the external processor 36. Next, the actual zero current value and the zero current value indicated by the equivalent zero current signal are determined by the external processor 36 (or by the user). Thereby, the external processor 36 can instruct the control The offset calibration unit 342 in module 34 correspondingly changes the offset parameter to eliminate the error between the equivalent zero current signal (indicating the actual zero current value) and the zero current signal (indicating the zero current value).

Similarly, during the calibration of the magnification, the equivalent fixed current signal generated by the computing module 32 is not directly fed into the control module 34, but is first fed into the external processor 36. Next, the external processor 36 (or by the user) determines the magnitude of the actual fixed current value and the fixed current value indicated by the equivalent fixed current signal. Thereby, the external processor 36 can instruct the magnification calibration unit 344 in the control module 34 to change the magnification parameter correspondingly to eliminate the equivalent fixed current signal (indicating the actual fixed current value) and the fixed current signal (indicating the fixed current value). The error between.

In summary, the motor monitoring system and the current detecting device provided by the embodiments of the present invention can first pass the two main parameters of the calibration current offset and the zooming ratio, so that the calibrated motor monitoring system and the current detecting thereof are obtained. The device accurately determines the exact value of the operating current in the motor or other electronic device. In addition, the motor monitoring system and the current detecting device provided by the embodiments of the present invention do not need to use a conventional Hall sensor, thereby eliminating the space-consuming coil and the heat energy generated when detecting a large current, thereby effectively reducing energy transmission. Heat or other forms are consumed.

The features and spirit of the present invention will be more apparent from the detailed description of the preferred embodiments. On the contrary, the intention is to cover various modifications and equivalents within the scope of the invention as claimed.

1‧‧‧ Current detecting device

10‧‧‧ Current sampling module to be tested

12‧‧‧ Computing Module

14‧‧‧Control Module

102‧‧‧ fixed resistance element

104‧‧‧Signal generating components

142‧‧‧Offset calibration unit

144‧‧‧ magnification calibration unit

16‧‧‧Electronic devices

2‧‧‧Motor monitoring system

20‧‧‧Motor

3‧‧‧ Current detecting device

30‧‧‧Measurement current acquisition module

32‧‧‧ Computing Module

34‧‧‧Control Module

342‧‧‧Offset calibration unit

344‧‧‧ magnification calibration unit

36‧‧‧External Processor

A, A’, B‧‧‧ connection endpoints

OP‧‧‧Operational Amplifier

R1, R2‧‧‧ resistance

C1‧‧‧ capacitor

1A is a functional block diagram of a current detecting device according to an exemplary embodiment of the present invention.

FIG. 1B is a functional block diagram of a current capture module to be tested according to an exemplary embodiment of the invention.

1C is a functional block diagram of a current detecting device according to another exemplary embodiment of the present invention.

2 is a functional block diagram of a motor monitoring system in accordance with an exemplary embodiment of the present invention.

FIG. 3 is a functional block diagram of a current detecting device according to still another exemplary embodiment of the present invention.

1‧‧‧ Current detecting device

10‧‧‧ Current sampling module to be tested

12‧‧‧ Computing Module

14‧‧‧Control Module

16‧‧‧Electronic devices

A, A’‧‧‧ connection endpoint

Claims (10)

A current detecting device includes: a current sampling module to be tested, coupled to an electronic device, detecting an operating current in the electronic device, and outputting a current signal to be measured; and an operation module coupled Receiving the current sampling module to be tested, adjusting the current signal to be tested according to at least one offset parameter and a magnification parameter to generate a first modified current signal; and a control module coupled to the computing module to provide The offset parameter and the magnification parameter; wherein the control module calculates the offset parameter and the magnification parameter by a calibration procedure. The current detecting device of claim 1, wherein when the control module performs the calibration procedure, the electronic device fixes the working current to at least one preset current value, and the current to be measured is captured. The group outputs a calibration current signal according to the preset current value, the operation module adjusts the calibration current signal to generate a second correction current signal, and the control module is based on an actual current value indicated by the second correction current signal. The preset current value is used to calculate the offset parameter and the magnification parameter. The current detecting device of claim 2, wherein the electronic device coupled to the current sampling module to be tested is a motor, and the current to be measured when the control module performs the calibration procedure The electronic device coupled to the module is a power supply. The current detecting device of claim 2, wherein the control module comprises an offset calibration unit and a magnification calibration unit, in the calibration procedure, The power supply device fixes the working current to a zero current value, and the current sampling module to be tested outputs a zero current signal according to the zero current value, and the computing module is based on a first preset parameter and a second pre- Setting a parameter to adjust the zero current signal to generate an equivalent zero current signal, the offset calibration unit calculating an actual zero current value and the magnitude of the zero current value indicated by the equivalent zero current signal The offset parameter. The current detecting device of claim 4, wherein after the offset calibration unit is adjusted in the calibration procedure, the power supply further fixes the operating current to a fixed current value, the current to be measured The capture module outputs the fixed current signal according to the fixed current value, and the operation module adjusts the fixed current signal according to the adjusted offset parameter and the second preset parameter to generate an equivalent fixed current signal. The magnification calibration unit calculates the magnification parameter based on an actual fixed current value indicated by the equivalent fixed current signal and the magnitude of the fixed current value. The current detecting device of claim 1, wherein the current sensing module to be tested comprises a copper plate coupled to the electronic device, and the current sampling module to be tested detects the operating current flow. A voltage difference generated by the copper plate is output, and the current signal to be tested is output according to the voltage difference. A motor monitoring system includes: a motor; and a current detecting device comprising: a current sampling module to be tested, coupled to the motor or a power supply, detecting one of the motor or the power supply Working current, and outputting a current signal to be measured; a computing module coupled to the current capturing module to be tested, at least according to one Offset parameter and first rate parameter adjust the current signal to be tested to generate a first modified current signal; and a control module coupled to the operation module to provide the offset parameter and the magnification parameter; wherein the calibration is performed When the control module is configured, the current detecting device is coupled to the power supply, and the power supply fixes the supplied operating current to at least one preset current value, and the current sampling module to be tested according to the preset current The value outputs a calibration current signal, the operation module adjusts the calibration current signal to generate a second correction current signal, and the control module compares an actual calibration current value indicated by the second correction current signal with the preset current The magnitude of the value is used to calculate the offset parameter and the magnification parameter. The motor monitoring system of claim 7, wherein the current sampling module to be tested comprises a copper plate, the copper plate is selectively coupled to the motor or the power supply, and the current sampling module to be tested Detecting a voltage difference on the copper plate, and outputting the current signal to be tested according to the voltage difference. The motor monitoring system of claim 7, wherein the control module comprises an offset calibration unit and a magnification calibration unit, wherein the power supply is fixed to provide a zero current value when the control module is calibrated, The current sampling module to be tested outputs a zero current signal according to the zero current value, and the computing module adjusts the zero current signal according to a first preset parameter and a second preset parameter to generate an equivalent zero current. The signal, the offset calibration unit calculates the offset parameter by comparing an actual zero current value indicated by the equivalent zero current signal with the magnitude of the zero current value. For example, the motor monitoring system described in claim 9 of the patent scope, wherein the control is calibrated After the module is adjusted and the offset calibration unit is adjusted, the power supply is fixedly provided with a fixed current value, and the current sampling module to be tested outputs the fixed current signal according to the fixed current value, and the operation module is adjusted according to the adjustment. The offset parameter and the second preset parameter adjust the fixed current signal to generate an equivalent fixed current signal, the ratio calibration unit is compared to an actual fixed current value indicated by the equivalent fixed current signal The magnitude of the fixed current value is used to calculate the magnification parameter.