A DC voltage control device automatic testing device and testing method thereof

Abstract

The application provides a kind of direct current voltage control device automatic testing device and its testing method, comprising: adjustable direct current power module, digital signal generation module, digital-analog conversion module, interface module and display module;Adjustable direct current power module input end connects AC 220V, output end connects direct current voltage control device automatic testing device;The input end of digital signal generation module is connected with the input end of interface module, and the output end is connected with the input end of digital-analog conversion module;The output end of digital-analog conversion module is connected with the output end of interface module;The output end of digital-analog conversion module is connected with the output end of interface module;The input end of display module is connected with the output end of interface module.The application generates test voltage by using hardware circuit, changes the change of test voltage from manual to automatic, and can adjust the direction and rate of test voltage variation, only needs several keys in the test process, simple operation, not only improves the efficiency, and guarantees the test precision.

Description

Technical Field

[0001] The present invention relates to the technical field of manufacturing, maintenance and repair of general electrical appliances, railway or rail transit locomotive electrical appliances, and in particular to the testing and repair of a voltage control device. Background Art

[0002] For voltage-controlled electrical devices like relays and solenoid valves, the typical testing method involves using an adjustable power supply, a voltmeter with acceptable accuracy, and an actuation indicator. Connecting the device to the test unit, the tester manually measures the actuation voltage and return voltage for each unit. During testing, the test voltage starts at zero and is quickly and manually increased to the rated operating voltage. Then, the voltage is returned to zero. The test unit is allowed to actuate once or twice. The voltage is then slowly increased, especially near the critical actuation point. The voltage is recorded at the point of actuation. The operating voltage is then raised to the rated voltage and then decreased. Just before the return to critical point, the voltage is slowly increased until the test unit actuates. The return voltage is recorded, and the voltage is returned to zero for the next test. During testing, the operating voltage must not fluctuate above or below the critical point. If the actuation voltage exceeds the critical point, the test unit actuates without achieving the desired actuation value. This requires a significant reduction in the voltage before the tester can restart the test. This results in slow testing, low efficiency, and high labor intensity. Summary of the Invention

[0003] In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide an automatic testing device and a testing method for a DC voltage control device, which is used to solve the problem in the prior art that the test voltage needs to be manually adjusted, resulting in slow testing speed, low efficiency, and high labor intensity for workers.

[0004] To achieve the above-mentioned and other related purposes, the present invention provides an automatic testing device for a DC voltage control device and a testing method thereof, comprising: an adjustable DC power supply module, a digital signal generating module, a digital-to-analog conversion module, an interface module, and a display module;

[0005] The input end of the adjustable DC power supply module is connected to AC 220V, and the output end is connected to the test device through the input end of the interface module to provide it with a stable DC working voltage;

[0006] The input end of the digital signal generating module is connected to the input end of the interface module, and the output end is connected to the input end of the digital-to-analog conversion module. The direction and frequency of the output voltage change of the digital-to-analog conversion module are controlled by selecting an external button and comparing the set value.

[0007] The output end of the digital-to-analog conversion module is connected to the output end of the interface module to output the converted DC voltage to the workpiece to be measured and the display module;

[0008] The output end of the digital-to-analog conversion module is connected to the output end of the interface module to provide a test voltage for the workpiece under test;

[0009] The input end of the display module is connected to the output end of the interface module to display the real-time voltage value output by the digital-to-analog conversion module.

[0010] In one embodiment of the present invention, the adjustable DC power supply module is an AC-DC DC regulated power supply with analog voltage controlled output.

[0011] In one embodiment of the present invention, the digital signal generating module includes: a pulse generator unit, a comparator unit, a control unit and a counter unit;

[0012] The input end of the pulse generator unit is connected to the output end of the control unit and the comparator unit, and the output end is connected to the input end of the control unit; by comparing the real-time voltage value output by the digital-to-analog conversion module, different pulse signals are output to control the output frequency of the counter unit;

[0013] The input end of the comparator unit is connected to the input end of the interface module and the output end of the counter unit, and the output end is connected to the input end of the pulse generator unit and the control unit; by comparing the set value input by the interface module and the real-time voltage value output by the digital-to-analog conversion module, a control signal is output to the pulse generator unit and the control unit to control the direction and frequency of the change of the output data of the counter unit;

[0014] The input end of the control unit is connected to the input end of the interface module, the output end of the comparator unit and the counter unit, and the output end is connected to the input end of the counter unit; the direction of the change of the output data of the counter unit is controlled by the selection button of the interface module or by comparing the set value input by the interface module with the real-time voltage value output by the digital-to-analog conversion module;

[0015] The output end of the counter unit is connected to the input end of the comparator unit and the digital-to-analog conversion module, and outputs a digital signal to the input end of the comparator unit and the digital-to-analog conversion module.

[0016] In one embodiment of the present invention, the digital value output by the digital signal generating module is twelve bits.

[0017] In one embodiment of the present invention, the comparator unit and the control unit monitor the output of the counter unit and the feedback signal of the workpiece being measured in real time, and automatically adjust the working state of the counter unit.

[0018] In one embodiment of the present invention, the pulse frequency output by the pulse generator unit is adjustable.

[0019] A method for testing a DC voltage control device automatic test device comprises the following steps:

[0020] (1) Press the first button UP, the pulse generator unit outputs a high-frequency pulse signal, and controls the counter unit to output a digital signal from zero to the input end of the comparator unit, the digital-to-analog conversion module and the control unit through the control unit. At the same time, the interface module inputs the set rated voltage value, the rising frequency turning value and the falling frequency turning value to the input end of the comparator unit. When the voltage value output by the digital-to-analog conversion module reaches the rising frequency turning value, the comparator unit outputs a control signal to the pulse generator unit to make it output a low-frequency pulse signal. At this time, the voltage output by the digital-to-analog conversion module increases at a slower rate. When the workpiece under test moves and receives the action signal, the counter unit pauses counting and records the voltage value of the display module at this time.

[0021] (2) Press the second button REUP, the pulse generator unit continues to output the high-frequency pulse signal, the output voltage value of the digital-to-analog conversion module rises to the rated voltage value, and the counter unit stops counting;

[0022] (3) Press the third button DOWN, the pulse generator unit outputs a high-frequency pulse signal, and controls the counter unit to count down through the control unit. When the voltage value output by the digital-to-analog conversion module reaches the turning value of the falling frequency, the comparator unit outputs a control signal to the pulse generator unit, causing it to output a low-frequency pulse signal. At this time, the voltage output by the digital-to-analog conversion module decreases at a slower rate. When the workpiece returns and receives the return signal, the counter unit stops counting and records the voltage value at this time on the display module.

[0023] (4) Press the fourth button RESET to reset the counter unit and the test ends.

[0024] As described above, the automatic test device and test method of the DC voltage control device of the present invention have the following beneficial effects: first, the present invention adopts a hardware circuit to generate the test voltage, and uses an adjustable DC power supply with analog voltage control output to provide the working voltage for the hardware circuit, thereby ensuring the output of uniform, stable and high-precision test voltage; second, the test voltage changes at a relatively high rate, but when approaching the critical point of action and return, the test voltage change rate is automatically reduced, which not only improves efficiency but also ensures accuracy; third, when the workpiece under test moves or returns, the test voltage change automatically stops, making it convenient for the tester to record the test data; finally, the change of the test voltage is changed from manual to automatic, and the test process only requires a few keystrokes, which is simple to operate, which not only improves efficiency but also reduces the labor intensity of the tester. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Shown is a structural block diagram of the present invention;

[0026] Figure 2Shown is a structural block diagram of a digital signal generating module of the present invention;

[0027] Figure 3 Shown is a schematic diagram of the interface module of the present invention;

[0028] Figure 4 Shown is a schematic diagram of the digital-to-analog conversion module of the present invention;

[0029] Figure 5 Shown is a schematic diagram of a pulse generator unit of the present invention;

[0030] Figure 6-8 Shown is a schematic diagram of a comparator unit of the present invention;

[0031] Figure 9-10 Shown is a schematic diagram of a control unit of the present invention;

[0032] Figure 11 Shown is a schematic diagram of a counter unit of the present invention.

[0033] Component number description

[0034] 1. Adjustable DC power supply module; 2. Digital signal generation module; 3. Digital-to-analog conversion module; 4. Interface module;

[0035] 5. Display module; 6. Pulse generator unit; 7. Comparator unit; 8. Control unit; 9. Counter unit. DETAILED DESCRIPTION

[0036] See also Figure 1-11 The following describes the embodiments of the present invention through specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through different specific embodiments. The details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other unless there is a conflict.

[0037] It should be noted that the illustrations provided in the following embodiments are merely schematic illustrations of the basic concept of the present invention. Therefore, the illustrations only show components related to the present invention and are not drawn according to the number, shape, and size of components in actual implementation. In actual implementation, the type, quantity, and proportion of each component may be changed arbitrarily, and the component layout may also be more complex.

[0038] See also Figure 1, the present invention provides a DC voltage control device automatic test device and test method thereof, comprising: an adjustable DC power supply module 1, a digital signal generation module 2, a digital-to-analog conversion module 3, an interface module 4 and a display module 5;

[0039] The adjustable DC power supply module 1 is an AC-DC DC regulated power supply controlled by analog voltage. Given that the DC working voltage of railways or rail transit is generally not higher than 110V and the limit voltage does not exceed 150V, a DC regulated power supply with an input terminal connected to AC 220V, an input control voltage of 0-10VDC, and an output DC voltage of 0-150V3A is adopted. The output terminal is connected to the test device through the input terminal of the interface module to provide it with a DC working voltage, thereby ensuring the output of a uniform, stable, and high-precision test voltage.

[0040] The input end of the digital signal generating module 2 is connected to the input end of the interface module 4, and the output end is connected to the input end of the digital-to-analog conversion module 3. By selecting the key and comparing the set value, the change direction and frequency of the output voltage of the digital-to-analog conversion module 3 are controlled;

[0041] See also Figure 3 The input end of interface module 4 includes a first button (UP), a second button (REUP), a third button (DOWN), and a fourth button (RESET), which control the output state of the device. The input end of interface module 4 also includes multiple sets of setting switches S1-S6, which respectively input the rated voltage value, the rising frequency transition value, and the falling frequency transition value to the three comparators of comparator unit 7. The input set values ​​are generally empirical values, but they can also be appropriately relaxed based on the operating voltage value after several field tests. In addition, the input end of interface module 4 also includes a feedback switch J4, which feeds the operating signal or return signal of the workpiece being tested back to digital signal generation module 2.

[0042] See also Figure 4 The output end of the digital-to-analog conversion module 3 is connected to the output end of the interface module 4, and the converted DC voltage is output to the workpiece under test and the display module 5, providing a test voltage for the workpiece under test.

[0043] The input end of the display module 5 is connected to the output end of the interface module 4 to display the real-time voltage value output by the digital-to-analog conversion module 3. A high-precision digital voltmeter is recommended for the display module 5. When test conditions are limited or the accuracy requirement is not high, an oscilloscope, multimeter or other voltage measuring device can also be used.

[0044] See also Figure 2 , the digital signal generating module 1 includes: a pulse generator unit 6, a comparator unit 7, a control unit 8 and a counter unit 9;

[0045] See also Figure 5The input end of the pulse generator unit 6 is connected to the output end of the control unit 8 and the comparator unit 7, and the output end is connected to the input end of the control unit 8; by comparing the real-time voltage value output by the digital-to-analog conversion module 3, different pulse signals are output to control the output frequency of the counter unit 9;

[0046] See also Figure 6-8 The input end of the comparator unit 7 is connected to the input end of the interface module 4 and the output end of the counter unit 9, and the output end is connected to the input end of the pulse generator unit 6 and the control unit 8; by comparing the set value input by the interface module 4 and the real-time voltage value output by the digital-to-analog conversion module 3, the control signal is output to the pulse generator unit 6 and the control unit 8 to control the direction and frequency of the data change output by the counter unit 9.

[0047] See also Figure 9-10 The input end of the control unit 8 is connected to the input end of the interface module 4, the output end of the comparator unit 7 and the counter unit 9, and the output end is connected to the input end of the counter unit 9; the direction of the change of the output data of the counter unit 9 is controlled by the selection button of the interface module 4, the set value input by the comparison interface module 4 and the real-time voltage value output by the digital-to-analog conversion module 3, and the feedback signal of the workpiece being measured.

[0048] See also Figure 11 , the output end of the counter unit 9 is connected to the input end of the comparator unit 7 and the digital-to-analog conversion module 3, and outputs a digital signal to the input end of the comparator unit 7 and the digital-to-analog conversion module 3;

[0049] See also Figure 1-11 The present invention simulates the slowing down of the test voltage's rate of change as it approaches the critical point of action during manual testing. The pulse generator unit 6 uses the MC14060B to generate pulse signals, and the MC14051B serves as the selector switch channel. The output pulse signals are input to the input of the control unit 8. By comparison, 2048 Hz and 8 Hz are preferred as high- and low-frequency counting pulses.

[0050] Press the first button UP to start the test. The pulse generator unit 6 starts working and outputs a high-frequency pulse signal to the counter unit 9. The counter unit 9 starts to output a digital signal from zero. At this time, the output voltage value begins to be displayed on the display module 5. The comparator unit 7 compares the real-time digital signal with the set value input by the interface module 4. When the output voltage value reaches the rising frequency turning point, the comparator unit 7 outputs a control signal to the control unit 8. After passing through the control unit 8, it is input to the pulse generator unit 6, causing it to output a low-frequency pulse signal. The output voltage increases at a slower rate. When the workpiece under test moves, the feedback switch J4 of the interface module 4 receives the action signal, the counter unit 9 pauses counting, and records the voltage value at this time on the display module 5.

[0051] When the test voltage is 150V, the corresponding 12-bit step size is 4096, with a step size of 0.0366V. The 10-bit step size is 0.1645V, and the 8-bit step size is even larger, at 0.5859V. Therefore, to improve test accuracy, the digital value output by counter unit 9 is 12 bits. Accordingly, the conversion chip of digital-to-analog conversion module 3 uses the 12-bit parallel port input chip MX7541. Counter unit 9 uses three 4-bit reversible counter chips MC14193 to form a 12-bit chip. To ensure output voltage stability, digital-to-analog conversion module 3 uses a precision controllable voltage regulator TL431 to provide the reference voltage for the AD conversion chip.

[0052] When the test voltage is 150V, the total value of the lower four bits of the output data of the counter unit 9 is only 15×150÷4096=0.55V. The position error of the turning point is maintained at 0.55V and does not affect the test accuracy. Therefore, in order to save costs, each group of comparators of the comparator unit 7 uses two four-bit comparator chips MC14585B to form an eight-bit comparator to collect the upper eight bits of the digital value output by the counter unit 9.

[0053] Press the second button REUP, the pulse generator unit 6 continues to output the high-frequency pulse signal. When the output voltage value rises to the rated voltage value, the comparator unit 7 outputs a control signal to the pulse generator unit 6 to stop working and the counter unit 9 stops counting.

[0054] Press the third button DOWN, the pulse generator unit 6 outputs a high-frequency pulse signal, and controls the counter unit 9 to count down through the control unit 8. When the output voltage value reaches the falling frequency turning value, the comparator unit 7 outputs a control signal to the pulse generator unit 6, causing it to output a low-frequency pulse signal. At this time, the output voltage decreases at a slower rate. When the workpiece returns, the feedback switch J4 of the interface module 4 receives the return signal, the counter unit 9 stops counting, and the voltage value at this time is recorded and displayed on the display module 5.

[0055] The high-order eight bits of the counter unit 9's output are also fed into the input of the control unit 8, which monitors the output voltage in real time. When the output voltage reaches zero or the rated value, the counter unit 9 stops counting. During normal operation, the comparator unit 7 determines whether the workpiece has reached its rated value. However, if the comparator unit 7 fails and the output voltage reaches the limit, the control unit 8 will directly stop the counter unit 9 to protect the workpiece.

[0056] Press the fourth button RESET to reset the counter unit 9 and the test ends.

[0057] See also Figure 1-11 , the testing method of the present invention comprises:

[0058] (1) Press the first button UP, the pulse generator unit 6 outputs a high-frequency pulse signal, and controls the counter unit 9 to output a digital signal from zero to the comparator unit 7, the digital-to-analog conversion module 3 and the input end of the control unit 8 through the control unit 8. At the same time, the interface module 4 inputs the set rated voltage value, the rising frequency turning value and the falling frequency turning value to the input end of the comparator unit 7. When the voltage value output by the digital-to-analog conversion module 3 reaches the rising frequency turning value, the comparator unit 7 outputs a control signal to the pulse generator unit 6, causing it to output a low-frequency pulse signal. At this time, the voltage output by the digital-to-analog conversion module 3 increases at a slower rate. When the workpiece to be measured moves and receives the action signal, the counter unit 9 pauses counting and records the voltage value of the display module 5 at this time.

[0059] (2) Press the second button REUP again, the pulse generator unit 6 continues to output the high-frequency pulse signal, the output voltage value of the digital-to-analog conversion module 3 rises to the rated voltage value, and the counter unit 9 stops counting;

[0060] (3) Press the third button DOWN, the pulse generator unit 6 outputs a high-frequency pulse signal, and controls the counter unit 9 to count down through the control unit 8. When the voltage value output by the digital-to-analog conversion module 3 reaches the falling frequency turning value, the comparator unit 7 outputs a control signal to the pulse generator unit 6, causing it to output a low-frequency pulse signal. At this time, the voltage output by the digital-to-analog conversion module 3 decreases at a slower rate. When the workpiece returns and receives the return signal, the counter unit 9 stops counting and records the voltage value of the display module 5 at this time.

[0061] (4) Press the fourth button RESET to reset the counter unit 9 and the test ends. Replace the workpiece to continue the test.

[0062] In summary, first, the present invention uses a hardware circuit to generate a test voltage, and uses an adjustable DC power supply with analog voltage control output to provide a working voltage for the hardware circuit, thereby ensuring a uniform, stable, and high-precision test voltage output; second, the test voltage changes at a relatively high rate, but automatically reduces the test voltage change rate when approaching the critical point of action and return, which not only improves efficiency but also ensures accuracy; third, when the workpiece under test moves or returns, the test voltage change automatically stops, making it convenient for the tester to record test data; finally, the change of the test voltage is changed from manual to automatic, and the test process only requires a few buttons, which is simple to operate, not only improving efficiency but also reducing the labor intensity of the tester. Therefore, the present invention effectively overcomes the various shortcomings of the prior art and has a high industrial utilization value.

[0063] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical principles disclosed herein are intended to be covered by the claims of the present invention.

Claims

1. A DC voltage control device automatic test device, characterized in that: include: Adjustable DC power supply module, digital signal generation module, digital-to-analog conversion module, interface module and display module; The input end of the adjustable DC power supply module is connected to AC 220V, and the output end is connected to the test device through the input end of the interface module to provide it with a stable DC working voltage; The input end of the digital signal generating module is connected to the input end of the interface module, and the output end is connected to the input end of the digital-to-analog conversion module. The direction and frequency of the output voltage change of the digital-to-analog conversion module are controlled by selecting an external button and comparing the set value. The output end of the digital-to-analog conversion module is connected to the output end of the interface module to output the converted DC voltage to the workpiece to be measured and the display module; The output end of the digital-to-analog conversion module is connected to the output end of the interface module to provide a test voltage for the workpiece under test; The input end of the display module is connected to the output end of the interface module to display the real-time voltage value output by the digital-to-analog conversion module; The digital signal generating module includes: a pulse generator unit, a comparator unit, a control unit and a counter unit; The input end of the pulse generator unit is connected to the output end of the control unit and the comparator unit, and the output end is connected to the input end of the control unit; by comparing the real-time voltage value output by the digital-to-analog conversion module, different pulse signals are output to control the output frequency of the counter unit; The input end of the comparator unit is connected to the input end of the interface module and the output end of the counter unit, and the output end is connected to the input end of the pulse generator unit and the control unit; by comparing the set value input by the interface module and the real-time voltage value output by the digital-to-analog conversion module, a control signal is output to the pulse generator unit and the control unit to control the direction and frequency of the change of the output data of the counter unit; The input end of the control unit is connected to the input end of the interface module, the output end of the comparator unit and the counter unit, and the output end is connected to the input end of the counter unit; the direction of the change of the output data of the counter unit is controlled by the selection button of the interface module or by comparing the set value input by the interface module with the real-time voltage value output by the digital-to-analog conversion module; The output end of the counter unit is connected to the input end of the comparator unit and the digital-to-analog conversion module, and outputs a digital signal to the input end of the comparator unit and the digital-to-analog conversion module; The adjustable DC power supply module is an AC-DC DC regulated power supply with analog voltage control output.

2. The automatic testing device for a DC voltage control device according to claim 1, characterized in that: The digital quantity output by the counter unit is twelve bits.

3. The automatic testing device for a DC voltage control device according to claim 2, characterized in that: The comparator unit and the control unit monitor the output of the counter unit and the feedback signal of the measured workpiece in real time, and automatically adjust the working state of the counter unit.

4. The automatic testing device for a DC voltage control device according to claim 3, characterized in that: The pulse frequency output by the pulse generator unit is adjustable.

5. The testing method of the automatic testing device for a DC voltage control device according to claim 4, characterized in that: The following steps are involved: (1) Press the first button UP, the pulse generator unit outputs a high-frequency pulse signal, and controls the counter unit to output a digital signal from zero to the input end of the comparator unit, the digital-to-analog conversion module and the control unit through the control unit. At the same time, the interface module inputs the set rated voltage value, the rising frequency turning value and the falling frequency turning value to the input end of the comparator unit. When the voltage value output by the digital-to-analog conversion module reaches the rising frequency turning value, the comparator unit outputs a control signal to the pulse generator unit to make it output a low-frequency pulse signal. At this time, the voltage output by the digital-to-analog conversion module increases at a slower rate. When the workpiece under test moves and receives the action signal, the counter unit pauses counting and records the voltage value of the display module at this time. (2) Press the second button REUP, the pulse generator unit continues to output the high-frequency pulse signal, the output voltage value of the digital-to-analog conversion module rises to the rated voltage value, and the counter unit stops counting; (3) Press the third button DOWN, the pulse generator unit outputs a high-frequency pulse signal, and controls the counter unit to count down through the control unit. When the voltage value output by the digital-to-analog conversion module reaches the turning value of the falling frequency, the comparator unit outputs a control signal to the pulse generator unit, causing it to output a low-frequency pulse signal. At this time, the voltage output by the digital-to-analog conversion module decreases at a slower rate. When the workpiece returns and receives the return signal, the counter unit stops counting and records the voltage value at this time on the display module. (4) Press the fourth button RESET to reset the counter unit and the test ends.

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