Electromagnet performance test system

Abstract

The invention discloses an electromagnet performance test system, a test device in the electromagnet performance test system comprises a driving assembly, a force sensor and a displacement sensor, the driving assembly can drive an armature of an electromagnet to act, the force sensor can detect the output force of the armature, and the displacement sensor can detect the displacement of the armature. Multi-physical-field parameters in the dynamic and static performance testing process of the electromagnet are collected, combined testing of dynamic and static characteristics of the electromagnet is achieved, the integration degree is high, the testing efficiency is improved, the electromagnet is driven through PWM signals, energy consumption and heat productivity can be reduced, the influence of temperature fluctuation caused by heating on the testing result is reduced, and the testing efficiency is improved. And the PWM signal is more suitable for quickly responding and simulating the working condition in an actual control system, efficiency and balance of current applied to the electromagnet can be considered, vibration generated by driving after the analog signal obtained after D / A conversion is adopted by the electromagnet is amplified is reduced, and the precision and reliability of a test result are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of performance testing of electromagnets, and particularly to a performance testing system for electromagnets. Background Art

[0002] As a device that generates a magnetic field through current excitation, based on its electromagnetic conversion characteristics, electromagnets are widely used in fields such as automatic control, magnetic drive, and lifting devices. The stability and reliability of the performance of electromagnets are crucial for the overall operation effect of related equipment.

[0003] The performance testing of electromagnets includes static and dynamic performance tests such as current-force characteristics, displacement-force characteristics, force-current step characteristics, displacement-current step characteristics, force frequency response characteristics, and displacement frequency response characteristics. Existing electromagnet performance testing devices are of a split modular design. The dynamic performance testing unit for testing the armature displacement, output force, and current step response of the electromagnet is independent of the static parameter acquisition, resulting in insufficient synchronization of multi-physical field coupling data and making it difficult to accurately capture the collaborative change law of the transient process, leading to dynamic hysteresis effects and deviations in performance evaluation. Moreover, when testing, the test signal of the upper computer is converted by D / A into a driving signal to drive the electromagnet through an analog signal as the driving signal, resulting in vibration of the electromagnet, interference with the test, and inaccurate test results. Summary of the Invention

[0004] Embodiments of the present invention provide a performance testing system for electromagnets to solve the problems that the dynamic performance and static performance tests in existing electromagnet performance testing are independent of each other and the driving signal after D / A conversion leads to inaccurate test results.

[0005] To solve the above technical problems, the present invention provides a performance testing system for electromagnets, including an upper computer, an acquisition board card, a driving circuit, a testing device, and a power supply for supplying power to the entire system. The acquisition board card is respectively connected to the upper computer and the driving circuit. The testing device includes a driving component, a frame, a displacement sensor, a first longitudinal displacement component located below the driving component for fixing the electromagnet, a force sensor located at the end of the driving component, and a force testing component with one end connected to the force sensor and the other end connected to the armature of the electromagnet. The displacement sensor, the driving component, and the first longitudinal displacement component are arranged on the frame, and the displacement sensor and the force sensor are also electrically connected to the upper computer;

[0006] The upper computer is configured to send a control signal to the acquisition board card and control the driving component to drive the armature to act when performing performance testing on the electromagnet to be tested;

[0007] The acquisition board is used to output a pulse signal to the drive circuit when receiving the control signal;

[0008] The drive circuit is used to output a PWM signal or an SPWM signal according to the pulse signal to drive the electromagnet, so that the armature moves;

[0009] The displacement sensor is used to detect the displacement of the armature through the force test module;

[0010] The force sensor is used to detect the output force of the armature;

[0011] The host computer is further used to receive the displacement of the armature from the displacement sensor and the output force of the armature from the force sensor, and generate the test result of the electromagnet according to the displacement, output force and test signal.

[0012] Optionally, the frame includes a stage and a vertical plate provided on the stage, the drive assembly includes a motor and a cylinder provided at the drive end of the motor, the cylinder is provided on the vertical plate and the output direction of the cylinder is in the vertical direction, and the force sensor is connected to the drive end of the cylinder.

[0013] Optionally, the cylinder can move horizontally on the vertical plate.

[0014] Optionally, the force test assembly includes an intermediate member connected to the force sensor, a first shielding member provided on the intermediate member, and a push-pull rod connected to the intermediate member. The push-pull rod is used to push or pull the armature, the first shielding member moves synchronously with the armature, and the displacement sensor detects the displacement of the first shielding member as the displacement of the armature.

[0015] Optionally, the first longitudinal displacement assembly includes a lifting assembly, a connecting seat and a supporting seat. The connecting seat is provided on the stage and can move horizontally on the stage. One end of the lifting assembly is connected to the connecting seat, and the other end is connected to the supporting seat. A second shielding member is provided at one end of the supporting seat away from the lifting assembly. An installation portion for installing the electromagnet is provided on the supporting seat. The lifting assembly can drive the supporting seat to move up and down in the vertical direction to drive the armature to move, and the displacement sensor detects the position of the second shielding member as the position of the armature.

[0016] Optionally, the test device further includes a second longitudinal displacement assembly, and the displacement sensor is connected to the vertical plate through the second longitudinal displacement assembly.

[0017] Optionally, the second longitudinal displacement assembly includes a handle, a coupling, and a lead screw mechanism. The lead screw mechanism is connected to the vertical plate. The displacement sensor is disposed on the slider of the lead screw mechanism. The handle is connected to the lead screw in the lead screw mechanism through the coupling. The lead screw mechanism is driven by the handle and the coupling, and the displacement sensor moves up and down in the vertical direction.

[0018] Optionally, the drive circuit includes a PWM drive circuit and an inverter circuit;

[0019] The input end of the PWM drive circuit is connected to the output end of the acquisition board. The output end of the PWM drive circuit is connected to the coil of the electromagnet. The PWM drive circuit is configured to output a PWM signal with a preset duty cycle to the coil of the electromagnet;

[0020] The input end of the inverter circuit is connected to the output end of the acquisition board. The output end of the inverter circuit is connected to the input end of the filter circuit. The output end of the filter circuit is connected to the coil of the electromagnet. The inverter circuit is configured to output an SPWM signal to the coil of the electromagnet through the filter circuit.

[0021] Optionally, the inverter circuit includes a modulation circuit and a full-bridge inverter circuit connected to the modulation circuit. The input end of the modulation circuit is connected to the output end of the acquisition board. The input end of the full-bridge inverter circuit is connected to the output end of the modulation circuit. The output end of the full-bridge inverter circuit is connected to the electromagnet.

[0022] Optionally, when testing the displacement-force characteristic of the electromagnet, the host computer is configured to:

[0023] Control the acquisition board to output a PWM signal with a constant duty cycle to the PWM drive circuit. The PWM drive circuit is configured to supply power to the electromagnet under the drive of the PWM signal with a constant duty cycle;

[0024] Control the drive assembly to output displacement in the vertical direction. The armature of the electromagnet moves under the drive of the drive assembly;

[0025] Receive the output force of the armature measured by the force sensor;

[0026] Generate a displacement-force characteristic test result of the electromagnet by using the displacement and the output force;

[0027] When testing the current-force characteristic of the electromagnet, the host computer is configured to:

[0028] Control the acquisition board to output PWM signals with different duty cycles to the PWM drive circuit. The PWM drive circuit is used to supply power to the electromagnet under the drive of PWM signals with different duty cycles, and the armature of the electromagnet moves. The supply current to the electromagnet is different for PWM signals with different duty cycles;

[0029] Receive the output force of the armature measured by the force sensor;

[0030] Generate the current-force characteristic test result of the electromagnet using the supply current and the output force;

[0031] When testing the force-current step characteristic of the electromagnet, the host computer is used to:

[0032] Control the acquisition board to output a PWM signal with a sudden change in duty cycle to the PWM drive circuit. The PWM drive circuit is used to apply a step current to the electromagnet under the drive of the PWM signal with a sudden change in duty cycle, and the armature of the electromagnet moves;

[0033] Receive the output force of the armature measured by the force sensor;

[0034] Generate the force-current step characteristic test result of the electromagnet using the step current and the output force;

[0035] When testing the force frequency response characteristic of the electromagnet, the host computer is used to:

[0036] Control the acquisition board to output a triangular wave signal and a sine wave signal to the inverter circuit. The inverter circuit is used to output an SPWM signal based on the triangular wave signal and the sine wave signal, and supply power to the electromagnet under the drive of the SPWM signal, and the armature of the electromagnet moves;

[0037] Receive the output force of the armature measured by the force sensor;

[0038] Generate the force frequency response characteristic test result of the electromagnet using the frequency of the SPWM signal and the output force.

[0039] In the electromagnet performance test system of the present invention, the test equipment includes a driving component, a force sensor, and a displacement sensor. The driving component can drive the armature of the electromagnet to move, the force sensor can detect the output force of the armature, and the displacement sensor can detect the displacement of the armature. Multiple parameters during the dynamic and static performance tests of the electromagnet can be collected, realizing the combined test of the dynamic and static characteristics of the electromagnet, with a high degree of integration and improved test efficiency. In addition, using a PWM signal to drive the electromagnet can reduce energy consumption and heat generation, reduce the influence of temperature fluctuations caused by heat on the test results, and the PWM signal is more suitable for rapid response and simulating the working conditions in an actual control system, capable of balancing efficiency and the current applied to the electromagnet, reducing the vibration generated by driving after amplifying the analog signal converted by D / A for the electromagnet, and improving the accuracy and reliability of the test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 FIG. is a schematic diagram of an electromagnet performance test system provided by an embodiment of the present invention;

[0041] Figure 2 FIG. is a front view of the test equipment in an embodiment of the present invention;

[0042] Figure 3 FIG. is a waveform diagram of PWM signals with various duty cycles;

[0043] Figure 4 FIG. is a waveform diagram of a triangular wave and a sine wave output by the acquisition board;

[0044] Figure 5 FIG. is a circuit schematic diagram of the inverter circuit;

[0045] Figure 6 FIG. is a waveform diagram of the SPWM signal.

[0046] In the figure:

[0047] 1. Driving component; 11. Motor; 12. Cylinder; 13. Air cushion; 14. Slide bar;

[0048] 2. Frame; 21. Carrier platform; 22. Vertical plate; 221. Slide groove;

[0049] 3. Displacement sensor;

[0050] 4. First longitudinal displacement component; 41. Lifting component; 42. Connecting seat; 43. Support seat; 44. Second shielding member;

[0051] 5. Force sensor;

[0052] 6. Electromagnet;

[0053] 7. Force testing component; 71. Middleware; 72. First shielding member; 73. Push-pull rod;

[0054] 8. Second longitudinal displacement component; 81. Handle; 82. Coupling; 83. Lead screw mechanism. Detailed implementation manner

[0055] The present invention will be further described in detail below with reference to the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. Additionally, it should be noted that for the sake of description, only the parts related to the present invention are shown in the drawings, rather than all the structures.

[0056] The electromagnet performance testing system of this embodiment is used to test the static performance and dynamic performance of the electromagnet. Among them, the static performance test includes current-force characteristics and displacement-force characteristics, and the dynamic performance test includes step characteristics and frequency response characteristics test.

[0057] As Figure 1 shown, the electromagnet performance testing system includes a host computer, an acquisition board card, a drive circuit, a test device, and a power supply for powering the entire system. The acquisition board card is respectively connected to the host computer and the drive circuit. An electromagnet test application program can be installed in the host computer. The acquisition board card is used to output a pulse signal to the drive circuit according to the test instruction of the application program. The drive circuit supplies power to the coil of the electromagnet through the drive signal to drive the electromagnet to work.

[0058] As Figure 1 and Figure 2 shown, the test device includes a drive component 1, a frame 2, a displacement sensor 3, a first longitudinal displacement component 4 located below the drive component 1 for fixing the electromagnet 6, a force sensor 5 located at the end of the drive component 1, and a force testing component 7 with one end connected to the force sensor 5 and the other end connected to the armature of the electromagnet 6. The displacement sensor 3, the drive component 1, and the first longitudinal displacement component 4 are arranged on the frame 2. The displacement sensor 3 and the force sensor 5 are also electrically connected to the host computer.

[0059] The material of the frame 2 can be metal, which is used to provide stable connection and support for other components of the entire system. The frame 2 includes a carrier 21 and a vertical plate 22 arranged on the carrier 21. Exemplarily, the vertical plate 22 is perpendicular to the carrier 21 and has a "T" - shaped structure. Among them, the vertical plate 22 can be connected to the carrier 21 by means of threaded connection or welding, etc. The carrier 21 is placed on a horizontal plane, so that the vertical plate 22 is arranged in the vertical direction. Optionally, floor bolts can also be provided at the four bottom corners of the bottom of the carrier 21, and the levelness of the carrier 21 can be adjusted through the floor bolts.

[0060] The driving component 1 includes a motor 11 and a cylinder 12 arranged at the driving end of the motor 11. The cylinder 12 is arranged on the vertical plate 22 and the output direction of the cylinder 12 is the vertical direction. The force sensor 5 is connected to the driving end of the cylinder 12. Specifically, the force sensor 5 is connected to the air cushion 13 at the driving end of the cylinder 12.

[0061] The force testing component 7 includes an intermediate member 71 connected to the force sensor 5, a first shielding member 72 arranged on the intermediate member 71, and a push-pull rod 73 connected to the intermediate member 71. The push-pull rod 73 is used to push or pull the armature of the electromagnet 6 located in the first longitudinal displacement component 4. Specifically, the push-pull rod 73 is directly connected to the force sensor 5 by a thread. The intermediate member 71 is fixed between the push-pull rod 73 and the force sensor 5 through the thread locking force between the push-pull rod 73 and the force sensor 5, so that the first shielding member 72 on the intermediate member 71 moves synchronously with the push-pull rod 73. When the end of the push-pull rod 73 away from the intermediate member 71 abuts or is detachably connected to the armature of the electromagnet 6, the first shielding member 72 can reflect the movement of the armature of the electromagnet 6, that is, the first shielding member 72 moves synchronously with the armature. Detecting the displacement of the first shielding member 72 by the displacement sensor 3 can be used as the displacement of the armature.

[0062] Through the above driving component 1 and force testing component 7, when the motor 11 in the driving component 1 drives the cylinder 12, the cylinder 12 outputs a driving force in the vertical direction. This driving force acts on the armature of the electromagnet 6 via the force sensor 5 and the push-pull rod 73. Similarly, when the armature of the electromagnet 6 outputs a force, it is also transmitted to the force sensor 5 through the push-pull rod 73, so that the force sensor 5 can detect the output force of the armature, ensuring that the force applied to the electromagnet 6 and the output force of the electromagnet 6 are along the vertical direction, avoiding the problem of test errors caused by lateral friction in the existing horizontal test structure during performance testing, and improving the test accuracy of the test equipment.

[0063] Due to the characteristic of rigidly transmitting the acting force of the force testing component 7, the push-pull rod 73 can push or pull the armature of the electromagnet 6. The force sensor 5 can accurately collect the output force of the armature after the electromagnet 6 inputs a PWM signal, and the displacement of the first shielding member 72 is detected by the displacement sensor 3 as the displacement of the armature. Through the displacement sensor 3, the force sensor 5 and the force testing component 7, the current-force characteristic, displacement-force characteristic, force step characteristic and force frequency response characteristic of the electromagnet 6 can be tested, improving the integration degree and test efficiency.

[0064] The first longitudinal displacement component 4 is used to fix the electromagnet 6 and adjust the position of the armature. Optionally, the first longitudinal displacement component 4 includes a lifting component 41, a connecting seat 42, and a support seat 43. The connecting seat 42 is disposed on the carrier 21 and can move horizontally on the carrier 21. One end of the lifting component 41 is connected to the connecting seat 42, and the other end is connected to the support seat 43. A second shielding member 44 is provided at one end of the support seat 43 away from the lifting component 41. An installation portion for installing the electromagnet 6 is provided on the support seat 43. The lifting component 41 can drive the support seat 43 to move up and down in the vertical direction to drive the armature to move. The displacement sensor 3 detects the position of the second shielding member 44 as the position of the armature.

[0065] Specifically, the support seat 43 is used to fix the electromagnet 6. The support seat 43 can be a rectangular plate. Through holes are provided on the plate surface of the rectangular plate. The main body of the electromagnet 6 can be installed on the lower side wall surface of the rectangular plate by means of a screwed fixing form, so that the armature of the electromagnet 6 passes upward through the through hole and then abuts or connects with the push rod 73. By horizontally adjusting the connecting seat 42, the push rod 73 and the armature are kept in the same vertical plane. Further, the armature of the electromagnet 6 is abutted or connected to the push rod 73 in the force test component 7 by vertically adjusting through the lifting component 41. In addition, the second shielding member 44 is disposed on the support seat 43 to reflect the position of the armature, so as to ensure whether the armature is within the detection stroke of the displacement sensor 3 during the test. The lifting component 41 is connected to the carrier 21 through the connecting seat 42, and the driving end of the lifting component 41 is connected to the support seat 43 for driving the support seat 43 to lift vertically. It should be noted that the lifting component 41 can be a manually driven component, that is, the lifting component 41 is manually driven to rise or fall.

[0066] In an alternative embodiment, a chute 221 extending in the horizontal direction is provided on the vertical plate 22. A sliding rod 14 can also be provided on the cylinder 12. After the sliding rod 14 is placed in the chute 221, the cylinder 12 can slide horizontally along the chute 221, so that the entire driving component 1 drives the force sensor 5 and the force test component 7 to slide horizontally along the chute 221. A locking mechanism can be provided at one end of the sliding rod 14 away from the cylinder 12. For example, a thread can be provided. After the driving component 1 is adjusted to the preset position in the horizontal direction through the chute 221, it is fixed by the cooperation of a nut and a gasket with the thread, so as to realize the fixation of the entire driving component 1 and the vertical plate 22.

[0067] Similarly, a chute may be provided on the stage 21, and the connecting seat 42 of the first longitudinal displacement assembly 4 can slide horizontally in the chute. By driving the assembly 1 and the first longitudinal displacement assembly 4 to slide cooperatively in the horizontal direction, it can be ensured that the armature of the electromagnet 6 fixed on the support seat 43 in the first longitudinal displacement assembly 4 and the push-pull rod 73 in the force test assembly 7 are located in the same vertical plane. Further, the position of the electromagnet 6 in the vertical direction is adjusted by the lifting assembly 41 in the first longitudinal displacement assembly 4, so that the armature of the electromagnet 6 is located directly below the push-pull rod 73 and is in contact with or detachably connected to the push-pull rod 73, ensuring the accuracy of the test.

[0068] In an alternative embodiment, the test device further includes a second longitudinal displacement assembly 8. The displacement sensor 3 is connected to the vertical plate 22 through the second longitudinal displacement assembly 8, so that the second longitudinal displacement assembly 8 can drive the displacement sensor 3 to move in the vertical direction.

[0069] Specifically, as Figure 2 shown, the second longitudinal displacement assembly 8 includes a handle 81, a coupling 82, and a lead screw mechanism 83. The lead screw mechanism 83 is connected to the vertical plate 22, and the displacement sensor 3 is disposed on the slider of the lead screw mechanism 83. The handle 81 is connected to the lead screw (which can be a ball screw) in the lead screw mechanism 83 through the coupling 82 (such as a cross coupling). By driving the lead screw mechanism 83 with the handle 81 and the coupling 82, the displacement sensor 3 moves up and down in the vertical direction. Among them, a through hole may be provided on the vertical plate 22, and the lead screw mechanism 83 can be disposed on the vertical plate 22 in a threaded connection manner through the through hole. The displacement sensor 3 can be a laser sensor. By driving the lead screw mechanism 83 with the handle 81, the displacement sensor 3 on the lead screw mechanism 83 moves up and down in the vertical direction, adjusting the distance between the displacement sensor 3 and the first shielding member 72 and the second shielding member 44, thereby realizing the adjustment of the measurement range of the displacement sensor 3 and expanding the actual use range of the displacement sensor 3.

[0070] In this embodiment, the drive circuit may include a PWM drive circuit and an inverter circuit. The input end of the PWM drive circuit is connected to the output end of the acquisition board, and the output end of the PWM drive circuit is connected to the coil of the electromagnet. The PWM drive circuit is used to output a PWM signal with a preset duty cycle to the coil of the electromagnet. In one embodiment, the PWM drive circuit may include one of electronic switches such as a high-frequency switching triode and a MOS tube and a relay. The PWM drive circuit may be a switching circuit that outputs a PWM signal. The PWM drive circuit is used to output a current with a constant direction to the coil of the electromagnet.

[0071] The input end of the inverter circuit is connected to the output end of the acquisition board, the output end of the inverter circuit is connected to the input end of the filter circuit, the output end of the filter circuit is connected to the coil of the electromagnet. The inverter circuit is used to output SPWM signals to the coil of the electromagnet through the filter circuit, and the inverter circuit is used to output a current with a changing direction to the coil of the electromagnet.

[0072] As Figure 3 shown in the waveform diagram of the PWM signal. When performing displacement-force characteristics, current-force characteristics, and step characteristics on the electromagnet, it is necessary to input a current or voltage signal with a fixed amplitude and a linear current or voltage signal whose amplitude rises and falls within a set range to the electromagnet. By adjusting the duty cycle of the PWM signal, the amplitude of the current or voltage signal can be adjusted. As Figure 3 shown in the schematic diagram of the duty cycle adjustment from 20% to 75%. For the frequency response characteristics, it is necessary to input sine voltage or current signals with different amplitudes and different frequencies to the coil of the electromagnet. Driving the coil of the electromagnet with a PWM signal is closer to actual application and has more valuable test performance.

[0073] Exemplarily, the PWM drive circuit can be a drive circuit including a power supply, a high-frequency switch (such as MOS or IGBT), and a relay. When performing displacement-force characteristics, current-force characteristics, and step characteristics on the electromagnet, the current applied to the electromagnet is linearly transformed and has only one current direction. The current change can be achieved by changing the duty cycle of the PWM signal. Specifically, the duty cycle required for different currents is calculated through the program in the upper computer. As shown in the appendix Figure 3 shown in the schematic diagram of the duty cycle from 25% to 75%. Subsequently, small PWM signals with different duty cycles are respectively applied to the high-frequency switch in the PWM drive circuit through the output port of the acquisition board by the upper computer, so that the PWM drive circuit outputs a PWM signal that conforms to the duty cycle to supply power to the electromagnet.

[0074] For the force frequency response characteristic test of the electromagnet, the force frequency response characteristic test has high requirements for the test equipment. It is necessary to not only ensure that the signal input to the coil of the electromagnet is not distorted, but also ensure that the hardware facilities can quickly respond to dynamically collect the required data. In this embodiment, a mode of supplying power to the coil of the electromagnet with an SPWM signal is adopted during the force frequency response characteristic test. Specifically, the control program in the upper computer controls the acquisition board to output a triangular wave and a sine wave as shown in Figure 4 . Among them, the triangular wave is the carrier wave, and the sine wave is the modulation wave also called the signal wave. The triangular wave and sine wave output by the acquisition board are input to the inverter circuit shown in Figure 5 . In the inverter circuit, a voltage comparator is set in the modulation circuit. By comparing the voltage amplitudes of the triangular wave and the sine wave, a logical judgment is made. Exemplarily, when u r >u cWhen the time is right, transistors V1 and V4 in the full-bridge inverter circuit are turned on, transistors V2 and V3 are turned off, and the output voltage is +U d . When u r < u c When the time is right, transistors V2 and V3 are turned on, transistors V1 and V4 are turned off, and the output voltage is -U d . The pulse voltage output by the full-bridge inverter circuit shows a sinusoidal variation law. After filtering with a filter (the filter is not shown in the figure, and the filter can be an LC filter circuit), an SPWM signal can be obtained

[0075] Among them, the modulation circuit has key modulation parameters. The carrier ratio m f = f c / f r , and the voltage modulation ratio M = u r / u c . Among them, f r is the sine wave frequency, f c is the carrier frequency, u r is the sine wave amplitude, u c is the carrier amplitude. By modulating the above parameters through the host computer program, different frequency SPWM signals as shown in the appendix Figure 6 are output to supply power to the coil of the electromagnet

[0076] In this embodiment, during the test, the host computer is used to send a control signal to the acquisition board and control the driving component 1 to drive the armature to move when performing a performance test on the electromagnet to be tested. The acquisition board is used to output a pulse signal to the driving circuit when receiving the control signal. The driving circuit is used to drive the electromagnet by outputting a PWM signal or an SPWM signal according to the pulse signal, so that the armature moves. The displacement sensor 3 is used to detect the displacement of the armature through the force test module, and the force sensor 5 is used to detect the output force of the armature. The host computer is also used to receive the displacement of the armature from the displacement sensor 3 and the output force of the armature from the force sensor 5, and generate a test result of the electromagnet according to the displacement, output force, and test signal

[0077] The following details the process of the electromagnet performance test system in this embodiment during the static and dynamic tests of the electromagnet

[0078] I. Displacement-force characteristic test

[0079] The host computer is used to control the acquisition board to output a PWM signal with a constant duty cycle to the PWM driving circuit. The PWM driving circuit is used to supply power to the electromagnet under the drive of the PWM signal with a constant duty cycle, control the driving component 1 to output displacement in the vertical direction, the armature of the electromagnet moves under the drive of the driving component 1, receive the output force of the armature measured by the force sensor 5, and generate a displacement-force characteristic test result of the electromagnet by using the displacement and the output force

[0080] Specifically, the electromagnet 6 is fixed on the support base 43 of the first longitudinal displacement component 4. By adjusting the connecting seat 42 along the horizontal direction through the slide rail of the stage 21 and coordinating with the horizontal movement of the driving component 1 on the chute 221, it is ensured that the push-pull rod 73 and the armature of the electromagnet 6 are on the same vertical plane. At the same time, it is necessary to ensure that the first shielding member 72 is directly below the displacement sensor 3. At this time, the driving component 1, the force sensor 5, the force test component 7, and the armature are rigidly connected. The control program in the upper computer controls the acquisition board to output a PWM signal with a constant duty cycle to the PWM drive circuit to supply power to the electromagnet coil. The support base 43 is adjusted to a suitable position through the lifting component 41 so that the push-pull rod 73 abuts or is connected to the armature. Then, the upper computer controls the driving component 1 to output a displacement amount that reciprocates in the vertical direction. The force sensor 5, the force test component 7, and the armature also displace synchronously with the driving component 1. The displacement of the first shielding member 72, which is also the displacement of the armature, is measured by the displacement sensor 3. At the same time, the output force of the electromagnet is measured by the force sensor 5, so as to obtain the output force of the electromagnet 6 at different displacements of the armature at each current. Then, the duty cycle is adjusted to change the current magnitude for multiple measurements, and the curves of different displacements and output forces at each current can be plotted as the displacement-force characteristic test results.

[0081] II. Current-Force Characteristic Test

[0082] The upper computer is used to control the acquisition board to output PWM signals with different duty cycles to the PWM drive circuit. The PWM drive circuit is used to supply power to the electromagnet under the drive of PWM signals with different duty cycles. The armature of the electromagnet moves. The PWM signals with different duty cycles supply different currents to the electromagnet. The output force of the armature measured by the force sensor 5 is received, and the current-force characteristic test results of the electromagnet are generated using the supply current and the output force.

[0083] Specifically, the electromagnet 6 is fixed on the support base 43 of the first longitudinal displacement component 4. The connecting seat 42 is adjusted to move horizontally through the slide rail of the carrier 21 and cooperate with the horizontal movement of the driving component 1 on the chute 221 to ensure that the push-pull rod 73 and the armature of the electromagnet 6 are on the same vertical plane. Rotate the intermediate member 71 to place the first shielding member 72 outside the measurement path of the displacement sensor 3, and make the second shielding member 44 located directly below the displacement sensor 3. Then, adjust the displacement sensor 3 to an appropriate measurement range through the second longitudinal displacement component 8. First, apply an appropriate current to the electromagnet to make the armature move. For example, make the armature move one-third of the stroke. Then, adjust the support base 43 to an appropriate position through the lifting component 41 to make the push-pull rod 73 abut or cooperate with the armature. Then, adjust the lifting component 41 to make the armature of the electromagnet 6 move, and the position of the armature is reflected by the second shielding member 44 and the displacement sensor 3, ensuring that the armature is in the working stroke during the current-force characteristic test. Keep the lifting component 41 in the first longitudinal displacement component 4 stationary to keep the electromagnet 6 unchanged in the vertical position direction. The upper computer control program controls the acquisition board to output PWM signals with different duty cycles and combines with the drive circuit to apply a current with a changing magnitude to the electromagnet coil. The armature moves, and the output force of the armature is transmitted to the force sensor 5. The output force of the electromagnet 6 is measured through the force sensor 5, so as to obtain the current-force characteristic of the electromagnet 6. Then, the position of the armature at different working strokes can be changed through the lifting component 41 for multiple measurements, and the current-force characteristics of the armature at different strokes are obtained, and the curves of different currents and output forces at each stroke are drawn as the current-force characteristic test results.

[0084] III. Force-Current Step Characteristic

[0085] When testing the force-current step characteristic of the electromagnet, the upper computer is used to control the acquisition board to output a PWM signal with a sudden change in duty cycle to the PWM drive circuit. The PWM drive circuit is used to apply a step current to the electromagnet under the drive of the PWM signal with a sudden change in duty cycle. The armature of the electromagnet moves, and the output force of the armature measured by the force sensor 5 is received, and the force-current step characteristic test result of the electromagnet is generated by using the step current and the output force.

[0086] Specifically, the electromagnet 6 is fixed on the support base 43 of the first longitudinal displacement component 4. Similarly, ensure that the second shielding member 44 is located directly below the displacement sensor 3, and adjust the displacement sensor 3 to a suitable measurement range through the second longitudinal displacement component 8. Adjust the support base 43 to a suitable position through the first longitudinal displacement component 4 so that the push rod 73 abuts or is cooperatively connected to the armature. First, apply a suitable current to the electromagnet, and then adjust the support base 43 to a suitable position through the lifting component 41 so that the push rod 73 abuts or is cooperatively connected to the armature. Adjust the lifting component 41 to move the armature of the electromagnet 6 and reflect the position of the armature through the second shielding member 44 and the displacement sensor 3. Ensure that the armature is in the working stroke during the force-current step response characteristic test. Keep the lifting component 41 in the first longitudinal displacement component 4 stationary so that the electromagnet 6 remains unchanged in the vertical position direction. Then, apply a step current signal with a sudden change in duty cycle output by the acquisition board controlled by the host computer control program via the drive circuit to the electromagnet 6. The armature moves, and the force is transmitted to the force sensor 5. Measure the output force of the electromagnet 6 through the force sensor 5, so as to obtain the characteristic of the output force of the electromagnet 6 changing with the current step. Change the position of the armature at different working strokes for multiple measurements to obtain the characteristics of the force of the electromagnet changing with the current step at different strokes. For each stroke, plot the curve of the output force at different currents as the test result of the force-current step response characteristic.

[0087] IV. Force Frequency Response Characteristic

[0088] When testing the force frequency response characteristic of the electromagnet, the host computer is used to control the acquisition board to output a triangular wave signal and a sine wave signal to the inverter circuit. The inverter circuit is used to output an SPWM signal based on the triangular wave signal and the sine wave signal, and supply power to the electromagnet under the drive of the SPWM signal. The armature of the electromagnet moves, receives the output force of the armature measured by the force sensor 5, and generates the test result of the force frequency response characteristic of the electromagnet by using the frequency of the SPWM signal and the output force.

[0089] Specifically, the electromagnet 6 is fixed on the support base 43 of the first longitudinal displacement assembly 4. Similarly, ensure that the second shielding member 44 is located directly below the displacement sensor 3, and adjust the displacement sensor 3 to an appropriate measurement range through the second longitudinal displacement assembly 8. Adjust the support base 43 to an appropriate position through the first longitudinal displacement assembly 4 so that the push rod 73 abuts or is connected in cooperation with the armature. First, apply an appropriate current to the electromagnet, and then adjust the support base 43 to an appropriate position through the lifting assembly 41 so that the push rod 73 abuts or is connected in cooperation with the armature. Adjust the lifting assembly 41 to move the armature of the electromagnet 6, and reflect the position of the armature through the second shielding member 44 and the displacement sensor 3. Ensure that the armature is in the working stroke during the force frequency response characteristic test. Keep the lifting assembly 41 in the first longitudinal displacement assembly 4 stationary so that the electromagnet 6 remains unchanged in the vertical position direction. Then, the upper computer controls the acquisition board to output triangular waves and sine waves to the inverter circuit, and the inverter circuit outputs SPWM signals to apply sine wave currents of different frequencies to the electromagnet. The armature moves, and the force is transmitted to the force sensor 5. The output force of the electromagnet 6 is measured through the force sensor 5, so as to obtain the characteristic of the output force of the electromagnet 6 changing with the current frequency. Change the position of the armature at different working strokes for multiple measurements to obtain the characteristics of the output force of the electromagnet at different frequencies of the current at different strokes. For each stroke, draw a curve of the output force at different frequencies of the current as the test result of the force frequency response characteristic.

[0090] The electromagnet performance test system in the embodiment of the present invention has the following beneficial effects:

[0091] (1) The upper computer controls the acquisition board to output PWM wave signals through a program. When the PWM wave acts on the drive circuit to output corresponding signals to supply power to the electromagnet, 1) PWM drive can significantly reduce energy consumption and heat generation, reducing the influence of temperature on the test accuracy; 2) PWM drive is more suitable for applications that require high-speed response, with high test accuracy; 3) High-frequency PWM + closed-loop control can balance efficiency and current smoothness, reducing the test error caused by the vibration of the electromagnet; 4) In an actual control system, PWM drive can provide a more realistic working condition simulation, improving the reliability of test data.

[0092] (2) The direction of the test force of the drive assembly on the electromagnet acts along the vertical direction, avoiding the test error caused by the horizontal friction force in the horizontal test structure, and improving the test accuracy.

[0093] (3) By abutting or connecting the push rod against or to the armature of the electromagnet, the function of pushing or pulling the armature of the electromagnet is realized. And through the connection between the force sensor and the push rod, it is ensured that the force sensor accurately collects the electromagnetic force on the armature through the push rod, and the displacement of the armature is collected through the first shielding member on the middleware. Thus, in the combined test of the current-force characteristic, displacement-force characteristic, force step characteristic, and force frequency response characteristic of the electromagnet, that is, the dynamic and static characteristics of the electromagnet are jointly determined, with a high degree of integration and higher test efficiency.

[0094] (4) The second longitudinal displacement component can drive the displacement sensor to move up and down in the vertical direction, expanding the test range of the displacement sensor. And through the cooperation of the displacement sensor and the first longitudinal displacement component, the position of the armature is measured in real time, so as to ensure that the current-force characteristic, step characteristic, and frequency response characteristic of the armature are tested within the working stroke.

[0095] Note that the above is only the preferred embodiment of the present invention and the applied technical principles. Those skilled in the art will understand that the present invention is not limited to the specific embodiments here. Various obvious changes, re-adjustments, and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments. Without departing from the concept of the present invention, more other equivalent embodiments can be included, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. An electromagnet performance testing system, characterized in that It includes a host computer, a data acquisition board, a drive circuit, a test device, and a power supply for powering the entire system. The data acquisition board is respectively connected to the host computer and the drive circuit. The test device includes a drive assembly (1), a frame (2), a displacement sensor (3), a first longitudinal displacement assembly (4) located below the drive assembly (1) for fixing an electromagnet, a force sensor (5) located at the end of the drive assembly (1), and a force test assembly (7) with one end connected to the force sensor (5) and the other end connected to the armature of the electromagnet (6). The displacement sensor (3), the drive assembly (1), and the first longitudinal displacement assembly (4) are arranged on the frame (2), and the displacement sensor (3) and the force sensor (5) are also electrically connected to the host computer; When performing a performance test on the electromagnet to be tested, the host computer is used to send a control signal to the data acquisition board and control the drive assembly (1) to drive the armature to move; When the data acquisition board receives the control signal, it is used to output a pulse signal to the drive circuit; The drive circuit is used to output a PWM signal or an SPWM signal according to the pulse signal to drive the electromagnet, so that the armature moves; The displacement sensor (3) is used to detect the displacement of the armature through the force test module; The force sensor (5) is used to detect the output force of the armature; The host computer is also used to receive the displacement of the armature from the displacement sensor (3) and the output force of the armature from the force sensor (5), and generate a test result of the electromagnet according to the displacement, output force, and test signal.

2. The electromagnet performance testing system according to claim 1, wherein The frame (2) includes a stage (21) and a vertical plate (22) arranged on the stage (21). The drive assembly (1) includes a motor (11) and a cylinder (12) arranged at the drive end of the motor (11). The cylinder (12) is arranged on the vertical plate (22) and the output direction of the cylinder (12) is the vertical direction. The force sensor (5) is connected to the drive end of the cylinder (12).

3. The electromagnet performance testing system according to claim 2, wherein The cylinder (12) can move horizontally on the vertical plate (22).

4. The electromagnet performance testing system according to claim 2, wherein The force test assembly (7) includes an intermediate member (71) connected to the force sensor (5), a first shielding member (72) arranged on the intermediate member (71), and a push-pull rod (73) connected to the intermediate member (71). The push-pull rod (73) is used to push or pull the armature. The first shielding member (72) moves synchronously with the armature, and the displacement sensor (3) detects the displacement of the first shielding member (72) as the displacement of the armature.

5. The electromagnet performance testing system according to claim 2, wherein The first longitudinal displacement component (4) includes a lifting component (41), a connecting seat (42), and a supporting seat (43). The connecting seat (42) is arranged on the stage (21) and can move horizontally on the stage (21). One end of the lifting component (41) is connected to the connecting seat (42), and the other end is connected to the supporting seat (43). A second shielding member (44) is provided at one end of the supporting seat (43) away from the lifting component (41). An installation portion for installing the electromagnet (6) is provided on the supporting seat (43). The lifting component (41) can drive the supporting seat (43) to move up and down in the vertical direction to drive the armature to move. The displacement sensor (3) detects the position of the second shielding member (44) as the position of the armature.

6. The electromagnet performance testing system according to claim 2, wherein The testing device further includes a second longitudinal displacement component (8). The displacement sensor (3) is connected to the vertical plate (22) through the second longitudinal displacement component (8).

7. The electromagnet performance testing system according to claim 6, characterized in that, The second longitudinal displacement component (8) includes a handle (81), a coupling (82), and a lead screw mechanism (83). The lead screw mechanism (83) is connected to the vertical plate (22). The displacement sensor (3) is arranged on the slider of the lead screw mechanism (83). The handle (81) is connected to the lead screw in the lead screw mechanism (83) through the coupling (82). By driving the lead screw mechanism (83) through the handle (81) and the coupling (82), the displacement sensor (3) moves up and down in the vertical direction.

8. The electromagnet performance testing system according to any one of claims 1-7, characterized in that, The drive circuit includes a PWM drive circuit and an inverter circuit; The input end of the PWM drive circuit is connected to the output end of the acquisition board. The output end of the PWM drive circuit is connected to the coil of the electromagnet. The PWM drive circuit is used to output a PWM signal with a preset duty cycle to the coil of the electromagnet. The input end of the inverter circuit is connected to the output end of the acquisition board. The output end of the inverter circuit is connected to the input end of the filter circuit. The output end of the filter circuit is connected to the coil of the electromagnet. The inverter circuit is used to output an SPWM signal to the coil of the electromagnet through the filter circuit.

9. The electromagnet performance testing system according to claim 8, characterized in that, The inverter circuit includes a modulation circuit and a full-bridge inverter circuit connected to the modulation circuit. The input end of the modulation circuit is connected to the output end of the acquisition board. The input end of the full-bridge inverter circuit is connected to the output end of the modulation circuit. The output end of the full-bridge inverter circuit is connected to the electromagnet.

10. The electromagnet performance testing system according to claim 9, wherein When testing the displacement-force characteristic of the electromagnet, the host computer is used for: Controlling the acquisition board to output a PWM signal with a constant duty cycle to the PWM drive circuit. The PWM drive circuit is used to supply power to the electromagnet under the drive of the PWM signal with a constant duty cycle. Controlling the drive component (1) to output displacement in the vertical direction. The armature of the electromagnet moves under the drive of the drive component (1). Receive the output force of the armature measured by the force sensor (5); Generate the displacement-force characteristic test result of the electromagnet by using the displacement and the output force; When testing the current-force characteristic of the electromagnet, the host computer is used for: Controlling the acquisition board to output PWM signals with different duty cycles to the PWM drive circuit. The PWM drive circuit is used to supply power to the electromagnet under the drive of the PWM signals with different duty cycles. The armature of the electromagnet moves, and the supply current to the electromagnet is different for the PWM signals with different duty cycles; Receive the output force of the armature measured by the force sensor (5); Generate the current-force characteristic test result of the electromagnet by using the supply current and the output force; When testing the force-current step characteristic of the electromagnet, the host computer is used for: Controlling the acquisition board to output a PWM signal with a sudden change in duty cycle to the PWM drive circuit. The PWM drive circuit is used to apply a step current to the electromagnet under the drive of the PWM signal with a sudden change in duty cycle, and the armature of the electromagnet moves; Receive the output force of the armature measured by the force sensor (5); Generate the force-current step characteristic test result of the electromagnet by using the step current and the output force; When testing the force frequency response characteristic of the electromagnet, the host computer is used for: Controlling the acquisition board to output a triangular wave signal and a sine wave signal to the inverter circuit. The inverter circuit is used to output an SPWM signal based on the triangular wave signal and the sine wave signal, and supply power to the electromagnet under the drive of the SPWM signal, and the armature of the electromagnet moves; Receive the output force of the armature measured by the force sensor (5); Generate the force frequency response characteristic test result of the electromagnet by using the frequency of the SPWM signal and the output force.

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