CN210514352U - Rotating speed performance testing device of built-in driving type brushless direct current motor - Google Patents
Rotating speed performance testing device of built-in driving type brushless direct current motor Download PDFInfo
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- CN210514352U CN210514352U CN201921866668.9U CN201921866668U CN210514352U CN 210514352 U CN210514352 U CN 210514352U CN 201921866668 U CN201921866668 U CN 201921866668U CN 210514352 U CN210514352 U CN 210514352U
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Abstract
The utility model relates to a built-in drive brushless DC motor's rotational speed capability test device for the realization is to accurate, convenient, the swift measurement of motor speed, and wherein the device specifically includes: the information processing module is used for carrying out logic calculation processing; the contact pin type connection probe comprises a power supply probe, a signal acquisition probe and a Vsp control probe, wherein the signal acquisition probe and the Vsp control probe are electrically connected with the information processing module, the signal acquisition probe is directly inserted into the back of a lead terminal of the motor or an equipotential point of the lead terminal so as to acquire the feedback frequency of the motor during operation and send the feedback frequency to the information processing module, the Vsp control probe is used for outputting Vsp control voltage to the motor, and the power supply probe is used for supplying power to the motor; the thermocouple is electrically connected with the information processing module and is used for detecting temperature rise data of each key part during the test operation of the motor and sending the temperature rise data to the information processing module; and the display device is electrically connected with the information processing module and is used for being controlled by the information processing module so as to display the test data.
Description
Technical Field
The utility model relates to a built-in drive type brushless DC motor's rotational speed capability test device.
Background
In the air conditioning industry, in order to satisfy the balance between the cooling and heating capacities of the air conditioner during normal operation, the rotating speed of the indoor and outdoor motors must be ensured to meet the system requirements, and the rotating speed is kept stable. In order to achieve the above purpose, the prior art considers that a built-in driving type brushless direct current motor is adopted, and the rotation speed of the motor is regulated by using an SVPWM (space vector pulse width modulation) speed regulation method. Therefore, whether the rotating speed performance of the brushless direct current motor can be accurately, conveniently and quickly measured and recorded in real time in the early development stage of the project product is of great significance to the development and application of the whole project product.
For a built-in drive type brushless direct current motor, for example, in the air conditioner industry, when the application development of the motor at present relates to the early-stage matching test of the rotating speed performance, a stroboscope test method, a sensor test method and a software test method are generally mainly adopted for testing.
(1) The scheme for measuring the rotating speed of the motor by the stroboscope comprises the following main operation methods: the light-emitting source of the stroboscope is aligned to the fan blade, the stroboscope is adjusted to emit short-time flash of specific frequency, when the frequency of the flash is close to or synchronous with the rotating speed of the fan blade of the motor to be detected, the phenomenon of visual persistence can occur during human flesh eye observation, the motor fan blade is sensed to stop nearly in the moving state, and the rotating speed reading on the stroboscope is the current rotating speed of the motor at the moment. This solution has three main limitations: firstly, the accuracy of measured data is high, the rotating speed of a motor is measured by a stroboscope, a point at which the rotating speed and the flashing frequency of the motor are close to synchronization needs to be observed and judged by human eyes, and the flashing frequency is generally adjusted by a knob, so that a large measurement error is easily caused; secondly, the stroboscope measuring method has requirements on the installation position of the motor, only those motors with fan blades exposed outside can be measured, the light emitting source of the stroboscope can directly irradiate the fan blades and the eyes of people need to directly observe the motors, and the stroboscope measuring method is almost ineffective for some motors which are installed in the unit and covered by the unit shell; thirdly, the light condition of the measuring environment is required, and the stroboscope is mainly based on the principle that the testing environment is often required to be in a dark place to be convenient to observe through the flash frequency and human eye observation.
(2) The scheme of testing the motor rotation speed by the sensor is mainly to make a special mark on the motor blade, then to use a photoelectric switch or a Hall sensor and other devices at a certain proper position away from the rotating surface of the blade to collect the high and low level or pulse signals generated when the motor runs through the mark, and then to calculate the frequency of the generated signals to obtain the actual rotation speed of the motor. The main disadvantages of this solution are: firstly, special treatment (induction marking) needs to be carried out on the surface of a motor fan blade, and a test sample can be damaged; and secondly, a signal acquisition device (sensor) is required to be arranged at a short distance from the surface of the fan blade so as to collect high and low level or pulse signals generated when the fan blade rotates. For some special situations of motor installation positions, such as when the motor is hidden in a unit, the installation and construction of the signal acquisition sensor are limited by the structure.
(3) The scheme for testing the rotating speed of the motor by the software testing method mainly utilizes the characteristic that a built-in circuit of the built-in driving type brushless direct current motor can directly output the feedback frequency during the power-on operation of the motor, collects the feedback frequency through customized software and hardware, and then converts the feedback frequency to obtain the real-time rotating speed during the operation of the motor. The main limitation of testing the motor by the software testing method is that the motor is required to be supported by specific software and a hardware mainboard, when a plurality of motors with different setting parameters are compared and tested, relevant software and hardware engineers are required to make corresponding changes on the software and hardware parameters, and generally, when the motor is just connected to the beginning of project development, if the matched software and hardware are not formed, the development progress of the motor must be delayed backwards, and the development efficiency and the project progress introduced by the motor are seriously influenced.
SUMMERY OF THE UTILITY MODEL
The utility model aims at providing a built-in drive brushless DC motor's rotational speed capability test device's hardware architecture treats that software personnel can realize accurate, convenient, the swift measurement to motor speed to the information processing module programming back wherein.
To this end, the rotation speed performance testing device of the built-in driving type brushless direct current motor comprises:
the information processing module is used for carrying out logic calculation processing;
the contact pin type connection probe comprises a power supply probe, a signal acquisition probe and a Vsp control probe, wherein the signal acquisition probe and the Vsp control probe are electrically connected with the information processing module, the signal acquisition probe is directly inserted into the back of a lead terminal of the motor or an equipotential point of the lead terminal so as to acquire the feedback frequency of the motor during operation and send the feedback frequency to the information processing module, the Vsp control probe is used for outputting Vsp control voltage to the motor, and the power supply probe is used for supplying power to the motor;
the thermocouple is electrically connected with the information processing module and is used for detecting temperature rise data of each key part during the test operation of the motor and sending the temperature rise data to the information processing module;
and the display device is electrically connected with the information processing module and is used for being controlled by the information processing module so as to display the test data.
Further, still include:
the terminal of the motor test power supply terminal is exposed and is used for accessing external electricity;
the output end of the AC-DC alternating current to direct current rectification module is electrically connected with the power supply probe;
and the input end of the voltage regulating circuit is electrically connected with the motor test power supply wiring terminal, the switch control end is electrically connected with the information processing module, and the output end of the voltage regulating circuit is electrically connected with the alternating current input port of the AC-DC alternating current-to-direct current rectifying module.
Further, still include:
and the power switch is connected in series with the power transmission line connected with the input end of the voltage regulating circuit and is used for controlling the on-off of the power supply of the rotating speed performance testing device.
Further, still include:
and the voltage regulating knob is electrically connected with the information processing module and is used for outputting a sliding resistance value to trigger the information processing module to change the PWM duty ratio output to the voltage regulating circuit.
Further, still include:
and the motor speed regulation knob is electrically connected with the information processing module and is used for outputting a sliding resistance value to trigger the information processing module to regulate the Vsp control voltage output to the motor.
Further, still include:
and the acousto-optic alarm information device is electrically connected with the information processing module and is used for giving an alarm when the real-time rotating speed of the motor to be detected is overspeed.
Further, the sound and light alarm information device is specifically an alarm indicator lamp.
Further, still include:
and the human-computer interaction device is electrically connected with the information processing module and is used for inputting a control command to the information processing module.
Further, the human-computer interaction device is specifically a keyboard.
Treat that the software personnel program the back to information processing module wherein, the utility model discloses a rotational speed capability test device has following beneficial effect:
1. the real-time rotating speed of the fan is obtained by collecting electric signal data of the lead terminal of the motor and performing arrangement calculation, and the accuracy of the speed measurement result is high;
2. the acquisition mode is obtained through the pin probe and the transmission lead, and the test device and the test site of a tester are freely selected and are not influenced by the installation position of the fan on the whole machine set;
3. the temperature rise test function is added, so that the temperature rise data of each key part of the tested fan motor can be synchronously tracked, and the operation reliability of the fan can be integrally evaluated conveniently.
Drawings
The present invention is further explained by using the drawings, but the embodiments in the drawings do not constitute any limitation to the present invention, and for those skilled in the art, other drawings can be obtained according to the following drawings without any inventive work.
Fig. 1 is the structure schematic diagram of the device for testing the rotating speed performance of the motor of the present invention.
Detailed Description
The invention will be further described with reference to the following examples.
The principle adopted by the embodiment is mainly converted to obtain the real-time rotating speed of the motor according to the special property that the built-in driving type brushless direct current motor can feed back and output a fixed number of pulses every one revolution, and the specific steps are as follows:
setting the motor to output m pulses every revolution, wherein the period of each pulse is T (unit: s), the feedback frequency is f (unit: Hz), the rotating speed of the motor is n,
then
According to
Can obtain the product
(unit: r/min).
It can be derived from the above formula that, for the m-pulse weekly built-in drive type brushless direct current motor, the real-time rotating speed of the motor can be conveniently converted by trying to acquire the real-time feedback frequency f of the motor.
Because the feedback frequency f of each motor is fixed when the motor leaves a factory, the real-time rotating speed n can be calculated only by measuring the real-time pulse number m when the motor rotates, and when the rotating speed is regulated, the rotating speed of the motor can be regulated according to the percentage by regulating the real-time motor voltage and regulating the ratio of the real-time voltage to the rated voltage of the motor as long as the voltage is in direct proportion to the rotating speed.
Based on the above technology, as shown in fig. 1, the rotation speed performance testing device of the embodiment is composed of a motor test power terminal 11, a display screen 2, a power switch 3, a motor speed regulation knob 4, a voltage regulation knob 5, a power plug 6, a connection probe 7, a thermocouple 8, an alarm indicator lamp 9, a keyboard 10, a storage module and an information processing module which are not shown in the figure, and the like.
In the foregoing, the information processing module is specifically a PLC controller or a single chip microcomputer, and is configured to perform logic calculation processing.
The storage module is a storage device such as flash, ram, rom and the like, is in communication connection with the information processing module, and is used for storing related data information collected by the connection probe 7 on one hand, so that the data can be called and calculated by the information processing module conveniently, and on the other hand, the calculation processing result of the data information by the information processing module is also stored, so that when a test user needs to use a memory function, the test results of previous times can be called through the keyboard 10 and the display screen 2.
The motor test power supply wiring terminal 11 comprises A, B, C, N four wiring terminals, and two wiring terminals in A/B/C, N are connected when external single-phase electricity is connected; the three terminals of A, B, C are connected when external three phase power is accessed.
The connecting probe 7 is mainly a contact pin type, and can be directly inserted into the back of a lead terminal of the motor or an equipotential point of the lead terminal to make effective contact with the lead terminal without influencing the normal operation of the motor. The connection probe 7 not only supplies power to the brushless direct current motor, but also collects frequency signals fed back by the brushless direct current motor, and specifically comprises a power supply probe, a signal collection probe and a Vsp control probe, wherein the Vsp control probe and the signal collection probe are respectively electrically connected with the information processing module, the signal collection probe is used for collecting feedback frequency f when the motor runs to the information processing module, and the information processing module converts the real-time rotating speed of the motor according to the feedback frequency f; the Vsp control probe is used for the information processing module to output Vsp control voltage to the motor so as to control the rotating speed of the motor; the power supply probe is used for supplying power to the brushless direct current motor, specifically, the rotating speed performance testing device is provided with a conventional PWM alternating current voltage regulating circuit, the motor test power supply wiring terminal 11 is connected with the input end of the PWM alternating current voltage regulating circuit after being connected with external electricity, the switch control end of the PWM alternating current voltage regulating circuit is electrically connected with the information processing module, and the output end of the PWM alternating current voltage regulating circuit is connected with the alternating current input port of the AC-DC rectifying circuit of the power supply module. The AC-DC conversion rectification module converts the AC voltage output by the front-end AC-AC voltage transformation part into the DC voltage for directly supplying power to the motor, and the output end of the AC-DC conversion rectification module is electrically connected with the power supply probe.
The port of the motor test power supply wiring terminal 1 is exposed outside the shell of the rotating speed performance testing device and can be compatible with single-phase and three-phase motor power supply input wiring.
When the device is used, the information processing module controls the output voltage of the PWM alternating-current voltage regulating circuit in a PWM mode, the output voltage is conveyed to the motor through the power supply probe, the actual input voltage of the motor is adjusted according to needs, and the adjusting requirements for high-voltage and low-voltage state tests in motor performance tests are met.
The power plug 6 is a conventional power input connector and is used for directly connecting to a mains supply socket to get electricity and supplying power to the rotating speed performance testing device (such as the display screen 2 and the information processing module).
The power switch 3 is a key switch, is connected in series with a power transmission line between the power plug 6 and the PWM alternating-current voltage regulating circuit, and is used for controlling the on-off of a power supply.
The voltage regulating knob 5 is an adjustable potentiometer and is electrically connected with the information processing module, and the information processing module regulates the PWM duty ratio output to the PWM alternating current voltage regulating circuit according to the sliding resistance value of the voltage regulating knob 5, so that the actual input voltage of the motor is regulated, and the simulation of the high-voltage and low-voltage working conditions of the motor in the test is met. Of course, the voltage regulation can also be realized by adjusting the sliding resistance value to change the winding ratio of the primary coil and the secondary coil of the autotransformer, and the adjustment is not described herein since the prior art is concerned.
The motor speed regulation knob 4 is also an adjustable potentiometer and is also electrically connected with the information processing module, and the information processing module regulates Vsp control voltage output to the motor according to the sliding resistance value of the motor speed regulation knob 4 so as to control the rotating speed of the motor.
The thermocouple 8 is pre-buried in each key spare part position of motor during the test, pre-buried in positions such as end cover, bearing, main chip, power module usually, and the thermocouple 8 is connected with the information processing module electricity for detect the temperature rise data of each key spare part when motor test operation gives the information processing module, make things convenient for the information processing module can evaluate motor operational reliability more comprehensively.
The display screen 2 is electrically connected with the information processing module and is used for displaying the real-time rotating speed and voltage of the motor and parameter data of each temperature point of the motor under the control of the information processing module, and meanwhile, a user can conveniently look up historical data and record related test data.
The warning indicator lamp 9 is electrically connected with the information processing module, and the processing module is electrically connected to control the warning indicator lamp 9 to be on when the real-time rotating speed of the tested motor exceeds the preset maximum rotating speed before the test, so that a experimenter is reminded of processing the exceeding of the rotating speed.
The keyboard 10 is a numeric keyboard 10 and comprises a '0-9' key, a decimal point key, a 'menu' key, an 'OK' key and a 'clear', wherein the '0-9' key and the decimal point key are used for setting digital parameters of the testing device, such as the number of pulses of the motor, the maximum rotating speed allowed to be adjusted by the motor and the like; the menu key is used for mode interface selection, such as a speed measuring mode, a speed regulating mode, a temperature rise measuring mode, a pressure regulating mode and the like; the 'OK' key is used for confirming the input selection of other keys; the "clear" key is used for deletion of other input information. The keyboard 10 is electrically connected with the information processing module, and is mainly used for setting corresponding parameters according to different built-in parameters of different motors (such as the number of output pulses per rotation cycle of the motor) when the rotating speed performance of the motor is tested, so that the information processing module can accurately convert the real-time rotating speed of the motor according to the input parameters, the feedback frequency of the motor and other information; the keyboard 10 can also set the maximum rotating speed of the motor according to the rated parameter information set by a manufacturer when the motor leaves a factory in a speed regulation mode, when the rotating speed of the motor exceeds the preset maximum rotating speed in the test process, the information processing module compares the real-time rotating speed with the preset rotating speed and then outputs alarm information to prompt a laboratory technician that the current rotating speed is over-speed, so that safety accidents or serious damage to experimental samples caused by long-time over-speed running of the motor are avoided.
Compared with other speed measuring methods frequently used in the prior application development of the brushless direct current motor in the current manufacturing industry, the rotating speed performance testing device of the embodiment mainly has the following advantages and beneficial effects:
1. the real-time rotating speed of the fan is obtained by collecting electric signal data of the lead terminal of the motor and performing arrangement calculation, and the accuracy of the speed measurement result is high;
2. the acquisition mode is obtained through the pin probe and the transmission lead, and the test device and the test site of a tester are freely selected and are not influenced by the installation position of the fan on the whole machine set;
3. the testing device can set parameters aiming at motors with different built-in parameters, has strong universality and can be applied to other parts tested by using electric signals;
4. the test system has a data memory function, and a test user can recall and look up test data for many times and inquire historical data;
5. the temperature rise test function is added, so that the temperature rise data of each key part of the tested fan motor can be synchronously tracked, and the operation reliability of the fan can be integrally evaluated;
6. the device has an input voltage regulation function, and can simulate the influence of high and low voltages on the rotating speed and the running reliability of the motor during actual power grid fluctuation;
7. the speed regulation device has a speed regulation function, when a speed regulation mode is selected, the speed regulation test can be independently carried out on the motor, and actual control parameters (such as Vsp voltage, PWM duty ratio and the like) required by a certain specific speed are recorded;
8. the motor overspeed alarm device has an overspeed alarm function, and can alarm a test user through the indicator lamp when the actual running rotating speed of the motor exceeds a preset rotating speed value, so that safety accidents or damage to a motor test sample caused by long-time overspeed running of the motor are avoided.
It should be noted that:
the specifications of the probe pin and the wire used by the connecting probe 7 can be selected from various applicable specifications, and are not limited by the line color of a certain specific wire; the acquisition of the electric signals of the motor can be directly obtained from a pin probe connected with a lead terminal of the motor, and also can be obtained from the connection of equipotential points of lead wires of other motors;
the keyboard 10 can be replaced by other human-computer interaction devices such as touch screen input and knob input, and only digital signals can be effectively input to set parameters;
the status display lamp used by the alarm indicator lamp 9 can also be replaced by the display screen 2 or other acousto-optic alarm information devices, so long as the purpose of effectively providing alarm information for the tester can be achieved;
the testing device of the embodiment is mainly used in a part inspection scene of the SVPWM controlled brushless DC motor (a motor capable of outputting pulse electric signals), wherein the brushless DC motor is generally divided into three types according to the control mode, namely square wave control, SVPWM control and FOC control.
Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the protection scope of the present application, and although the present application is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions can be made on the technical solutions of the present application without departing from the spirit and scope of the technical solutions of the present application.
Claims (9)
1. A rotation speed performance testing device of a built-in driving type brushless DC motor is characterized by comprising:
the information processing module is used for carrying out logic calculation processing;
the contact pin type connection probe comprises a power supply probe, a signal acquisition probe and a Vsp control probe, wherein the signal acquisition probe and the Vsp control probe are electrically connected with the information processing module, the signal acquisition probe is directly inserted into the back of a lead terminal of the motor or an equipotential point of the lead terminal so as to acquire the feedback frequency of the motor during operation and send the feedback frequency to the information processing module, the Vsp control probe is used for outputting Vsp control voltage to the motor, and the power supply probe is used for supplying power to the motor;
the thermocouple is electrically connected with the information processing module and is used for detecting temperature rise data of each key part during the test operation of the motor and sending the temperature rise data to the information processing module;
and the display device is electrically connected with the information processing module and is used for being controlled by the information processing module so as to display the test data.
2. The apparatus for testing rotational speed performance of claim 1, further comprising:
the terminal of the motor test power supply terminal is exposed and is used for accessing external electricity;
the output end of the AC-DC alternating current to direct current rectification module is electrically connected with the power supply probe;
and the input end of the voltage regulating circuit is electrically connected with the motor test power supply wiring terminal, the switch control end is electrically connected with the information processing module, and the output end of the voltage regulating circuit is electrically connected with the alternating current input port of the AC-DC alternating current-to-direct current rectifying module.
3. The apparatus for testing rotational speed performance of claim 2, further comprising:
and the power switch is connected in series with the power transmission line connected with the input end of the voltage regulating circuit and is used for controlling the on-off of the power supply of the rotating speed performance testing device.
4. The apparatus for testing rotational speed performance of claim 2, further comprising:
and the voltage regulating knob is electrically connected with the information processing module and is used for outputting a sliding resistance value to trigger the information processing module to change the PWM duty ratio output to the voltage regulating circuit.
5. The apparatus for testing rotational speed performance of claim 1, further comprising:
and the motor speed regulation knob is electrically connected with the information processing module and is used for outputting a sliding resistance value to trigger the information processing module to regulate the Vsp control voltage output to the motor.
6. The apparatus for testing rotational speed performance of claim 1, further comprising:
and the acousto-optic alarm information device is electrically connected with the information processing module and is used for giving an alarm when the real-time rotating speed of the motor to be detected is overspeed.
7. A speed performance testing device according to claim 6, characterized in that the audible and visual alarm information device is in particular an alarm indicator lamp.
8. The apparatus for testing rotational speed performance of claim 1, further comprising:
and the human-computer interaction device is electrically connected with the information processing module and is used for inputting a control command to the information processing module.
9. The device for testing the rotating speed performance of claim 8, wherein the human-computer interaction device is a keyboard.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921866668.9U CN210514352U (en) | 2019-10-31 | 2019-10-31 | Rotating speed performance testing device of built-in driving type brushless direct current motor |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201921866668.9U CN210514352U (en) | 2019-10-31 | 2019-10-31 | Rotating speed performance testing device of built-in driving type brushless direct current motor |
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| CN210514352U true CN210514352U (en) | 2020-05-12 |
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| CN201921866668.9U Active CN210514352U (en) | 2019-10-31 | 2019-10-31 | Rotating speed performance testing device of built-in driving type brushless direct current motor |
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