An automatic inspection method for intrinsically safe power supply for mines

Abstract

The invention discloses an automatic inspection method for an intrinsically safe power supply for mining, which belongs to the technical field of power supply inspection. The invention automatically controls the disconnection of an adjustable load unit through a core control unit, and adjusts the input voltage U of the intrinsically safe power supply under test. i is the rated voltage of the intrinsically safe power supply; then the core control unit automatically adjusts the duty cycle of the PWM pulse width modulation signal output by itself to control the input voltage U of the intrinsically safe power supply under test i At the same time, the core control unit intensively collects and caches the input voltage U of the intrinsically safe power supply under test. i And output voltage U o ; When the core control unit detects the output voltage U o Lower than input voltage U i When the input voltage U of the intrinsically safe power supply under test reaches 80%, record the input voltage U of the intrinsically safe power supply under test. i The value is the overvoltage protection value of the intrinsically safe power supply under test. The present invention can greatly improve the inspection efficiency, reduce the manual participation, and improve the inspection precision, accuracy and consistency; and meet the inspection requirements of the key parameters of the intrinsically safe power supply.

Description

Technical Field

[0001] The invention belongs to the technical field of power supply inspection, and in particular relates to an automatic inspection method for an intrinsically safe power supply for mining. Background Art

[0002] With the gradual development of intelligent and digital coal mines, more and more intrinsically safe monitoring and surveillance equipment are being applied to coal mines. In order to ensure the safe production of coal mines and the stable, accurate and reliable operation of intrinsically safe monitoring and surveillance equipment, the safety and stability of the intrinsically safe power supply for mines (hereinafter referred to as the intrinsically safe power supply) used to power the intrinsically safe monitoring and surveillance equipment must be guaranteed. Therefore, the inspection of the key parameters of the intrinsically safe power supply is crucial. The key parameters of the intrinsically safe power supply mainly include overvoltage protection value, overcurrent protection value, maximum output voltage deviation value, protection interval time and protection recovery process. Among them, the protection interval time is the safety indicator of the intrinsically safe power supply; the maximum output voltage deviation value and the protection recovery process are the performance indicators of the intrinsically safe power supply; the overvoltage protection value and the overcurrent protection value are both safety indicators and performance indicators.

[0003] In the prior art, conventional testing devices are used to test the key parameters of intrinsically safe power supplies. Figure 1 This is a schematic diagram of the connection structure of a conventional inspection device. Figure 1 The conventional inspection device shown in the figure has the following conventional inspection steps:

[0004] (1) Disconnect switch 5 and adjust the output voltage of DC regulated power supply 1 to the rated voltage U of the intrinsically safe power supply 3 under test. 1 ;

[0005] (2) Slowly increase the input voltage and observe the two voltmeters at all times. Record the value of the first voltmeter 2 before the value of the second voltmeter 4 drops, which is recorded as U 2 ;

[0006] (3) Restore the input voltage to U 1 , adjust the sliding rheostat 7 to the maximum; turn on the switch 5, slowly reduce the resistance of the sliding rheostat 7, and always observe the values ​​of the second voltmeter 4 and the ammeter 6, and record the value U of the second voltmeter 4 before the value of the ammeter 6 drops 3 And the current meter 6 shows the value I 1 ;

[0007] (4) Observe the oscilloscope 8, read the interval time T between two protection restorations, and observe the waveform of the voltage rising from zero to the maximum value;

[0008] (5) Switch to another level of protection and repeat the test.

[0009] Since the key parameters of the intrinsically safe power supply belong to dynamic limit values, and there is a certain step phenomenon in the adjustment process of the conventional inspection device used for inspection, the voltmeter, ammeter and other instruments of the conventional inspection device also have a certain degree of hysteresis; therefore, it is very likely that the critical value cannot be detected during the adjustment and measurement process. In order to get infinitely close to the true result, it is necessary to take the limit value as the measurement result after multiple measurements. The inspection process is cumbersome and inefficient. In addition, since the measurement process requires full human participation, operational errors will be introduced, affecting the measurement accuracy.

[0010] Through the above steps of testing the key parameters of the intrinsically safe power supply, it can be seen that the testing process requires the detection of voltage, current, and time, and the waveform display of the recovery process is required; in addition, it can be seen from the conventional testing steps that in order to meet the automatic testing, the input voltage and load current of the intrinsically safe power supply need to be automatically and continuously controlled. In order to meet the above needs and overcome the problems of the above-mentioned cumbersome measurement process and manual participation affecting the measurement accuracy, it is necessary to develop an automatic testing method for intrinsically safe power supplies for mines. Summary of the invention

[0011] The present invention aims at the above-mentioned problems, makes up for the deficiencies of the prior art, and provides an automatic inspection method for an intrinsically safe power supply for mining.

[0012] To achieve the above purpose, the present invention adopts the following technical solution.

[0013] The invention provides an automatic inspection method for an intrinsically safe power supply for mining. The method uses an automatic detection device for intrinsically safe power supply for mining to automatically inspect key parameters of an intrinsically safe power supply under test. The automatic detection device for intrinsically safe power supply for mining comprises a power supply, a voltage adjustment unit, an adjustable load unit, a current detection unit, a voltage detection unit, a display unit, a communication unit, a protection switching unit and a core control unit. The power supply is connected to the voltage adjustment unit, the voltage adjustment unit is connected to the core control unit, the adjustable load unit is connected to the current detection unit, the adjustable load unit and the current detection unit are respectively connected to the core control unit, the display unit and the communication unit are respectively connected to the core control unit, the protection switching unit is connected to the core control unit, the protection switching unit adopts a relay, and the relay is used to be respectively connected to the input end of the intrinsically safe power supply under test, the connection point between the previous heavy protection output end and the next heavy protection input end, and the output end;

[0014] The voltage detection unit includes a power supply voltage detection unit, an input voltage detection unit, and an output voltage detection unit. The power supply voltage detection unit is respectively connected to the power supply, the voltage regulating unit, and the core control unit, and the power supply voltage detection unit is used to detect the output voltage of the power supply; the input voltage detection unit is respectively connected to the voltage regulating unit and the core control unit, and the input voltage detection unit is used to detect the input voltage output to the intrinsically safe power supply under test after adjustment by the voltage regulating unit, and the voltage regulating unit and the input voltage detection unit are both used to be connected to the input end of the intrinsically safe power supply under test; the output voltage detection unit is respectively connected to the adjustable load unit and the core control unit, and the output voltage detection unit is used to detect the output voltage of the intrinsically safe power supply under test, and the adjustable load unit, the current detection unit, and the output voltage detection unit are all used to be connected to the output end of the intrinsically safe power supply under test;

[0015] The automatic inspection method for the intrinsically safe power supply for mining includes automatically inspecting the overvoltage protection value of the intrinsically safe power supply under test: in the initial state, the core control unit automatically controls the adjustable load unit to disconnect and adjusts the input voltage U of the intrinsically safe power supply under test. i is the rated voltage of the intrinsically safe power supply; then the core control unit automatically adjusts the duty cycle of the PWM pulse width modulation signal output by itself to control the input voltage U of the intrinsically safe power supply under test i At the same time, the core control unit intensively collects and caches the input voltage U of the intrinsically safe power supply under test. i And output voltage U o ; When the core control unit detects the output voltage U o Lower than input voltage U i When the input voltage U of the intrinsically safe power supply under test reaches 80%, record the input voltage U of the intrinsically safe power supply under test. i The value is the overvoltage protection value of the intrinsically safe power supply under test;

[0016] Automatically check the overcurrent protection value of the tested intrinsically safe power supply: In the initial state, the core control unit automatically controls the adjustable load unit to disconnect and adjusts the input voltage U of the tested intrinsically safe power supply. i is the rated voltage of the intrinsically safe power supply; then the core control unit automatically adjusts the duty cycle of the PWM pulse width modulation signal output by itself to control the load current I of the intrinsically safe power supply under test o At the same time, the core control unit intensively collects and caches the load current I of the intrinsically safe power supply under test. o And output voltage U o ; When the core control unit detects the output voltage U o Lower than input voltage U i When the load current I of the intrinsically safe power supply under test during this adjustment period reaches 50%, the acquisition and caching are stopped, and the load current I of the intrinsically safe power supply under test during this adjustment period is filtered and recorded from the cached data. oThe maximum value is the overcurrent protection value of the intrinsically safe power supply under test;

[0017] Automatically check the maximum output voltage deviation value of the tested intrinsically safe power supply: In the initial state, the core control unit automatically controls the adjustable load unit to disconnect and adjusts the input voltage U of the tested intrinsically safe power supply. i is the rated voltage of the intrinsically safe power supply; then the core control unit automatically adjusts the duty cycle of the PWM pulse width modulation signal output by itself to control the load current I of the intrinsically safe power supply under test o At the same time, the core control unit intensively collects and caches the load current I of the intrinsically safe power supply under test. o 、Input voltage U i And output voltage U o ; When the core control unit detects the output voltage U o Lower than input voltage U i When the load current I of the intrinsically safe power supply under test during this adjustment period reaches 50%, the acquisition and caching are stopped, and the load current I of the intrinsically safe power supply under test during this adjustment period is filtered and recorded from the cached data. o The input voltage U corresponding to the maximum value i And the output voltage U o The value of input voltage U i And the output voltage U o The difference is the maximum output voltage deviation of the intrinsically safe power supply under test;

[0018] Automatically check the protection interval time of the intrinsically safe power supply under test: In the initial state, the core control unit automatically controls the adjustable load unit to disconnect and adjusts the input voltage U of the intrinsically safe power supply under test. i is the rated voltage of the intrinsically safe power supply; then the core control unit automatically adjusts the duty cycle of the PWM pulse width modulation signal output by itself to control the load current I of the intrinsically safe power supply under test o Increases until the overcurrent protection is executed, and the load current I o When it drops to zero, record the time as t 0 ; Keep the load unchanged, and then the core control unit intensively collects the load current I of the intrinsically safe power supply under test o , record the load current I of the intrinsically safe power supply under test o The time when it rises and then drops to zero again is t 1 , t 0 to 1 The elapsed time is the protection interval time T of the intrinsically safe power supply under test. 1 ;

[0019] Automatically check the protection recovery process of the tested intrinsically safe power supply: In the initial state, the core control unit automatically controls the adjustable load unit to disconnect and adjusts the input voltage U of the tested intrinsically safe power supply.i is the rated voltage of the intrinsically safe power supply; the core control unit automatically adjusts the duty cycle of the PWM pulse width modulation signal output by itself to control the load current I of the intrinsically safe power supply under test o Increases until the overcurrent protection is executed, and the load current I o When it drops to zero, the load is kept unchanged, and then the core control unit intensively collects the load current I of the intrinsically safe power supply under test. o ; When the load current I o When rising from zero, record the time as t 2 At the same time, the core control unit starts to intensively record the load current I of the intrinsically safe power supply under test o until the load current I of the intrinsically safe power supply under test o When it drops to zero again, record the time as t 3 and stop recording I o ;t 2 to 3 The elapsed time is the time T of the recovery process of the tested intrinsically safe power supply 2 , combined with the load current I of the intrinsically safe power supply under test recorded during the period o The data reflects the protection recovery process of the tested intrinsically safe power supply.

[0020] Furthermore, the automatic inspection method for the intrinsically safe power supply for mining also includes automatically inspecting the voltage level of the intrinsically safe power supply under test: inspecting the power supply voltage U P The core control unit collects and determines the voltage level of the intrinsically safe power supply under test.

[0021] Furthermore, if the supply voltage U P The range is: U P ≥26V, it is determined that the voltage level of the tested intrinsically safe power supply is 24V.

[0022] Furthermore, if the supply voltage U P The range is: 20V≤U P <26V, it is determined that the voltage level of the tested intrinsically safe power supply is 18V.

[0023] Furthermore, if the supply voltage U P The range is: 14V≤U P <20V, it is determined that the voltage level of the tested intrinsically safe power supply is 12V voltage level.

[0024] Furthermore, if the supply voltage U P The range is: U P <14V, it is determined that the intrinsically safe power supply under test is faulty.

[0025] Furthermore, the automatic inspection method for intrinsically safe power supplies for mining also includes automatic inspection of the intrinsically safe power supply under test under automatic switching of different heavy protection positions: in an initial state, the core control unit automatically controls the relay to disconnect one level of protection of the intrinsically safe power supply under test, so that the one level of protection takes effect, and short-circuit the remaining heavy protections to make the remaining heavy protections invalid; when the parameter inspection of the intrinsically safe power supply under the one level of protection is completed, the core control unit automatically controls the relay to short-circuit the one level of protection to make the one level of protection invalid, and disconnect any other uninspected protection to make any other protection take effect, and re-inspect the parameters of the intrinsically safe power supply under test until the parameters of the intrinsically safe power supply under all heavy protections are inspected.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The invention provides an automatic inspection method for intrinsically safe power supplies for mining, which can greatly improve inspection efficiency, reduce manual participation, and improve inspection precision, accuracy and consistency; and meets the inspection requirements for key parameters of intrinsically safe power supplies. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic block diagram of the connection structure of a conventional inspection device;

[0029] Figure 2 The present invention is a schematic block diagram of the connection structure of a mine intrinsically safe power supply automatic detection device used in a mine intrinsically safe power supply automatic inspection method.

[0030] Markings in the figure: 1 is a DC regulated power supply, 2 is a first voltmeter, 3 is a tested intrinsically safe power supply, 4 is a second voltmeter, 5 is a switch, 6 is an ammeter, 7 is a sliding rheostat, 8 is an oscilloscope, 9 is a power supply, 10 is a power supply voltage detection unit, 11 is a voltage regulating unit, 12 is an input voltage detection unit, 13 is an output voltage detection unit, 14 is an adjustable load unit, 15 is a current detection unit, 16 is a communication unit, 17 is a core control unit, and 18 is a display unit. DETAILED DESCRIPTION

[0031] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. It should be understood that the specific implementation methods described herein are only used to explain the present invention and are not used to limit the present invention.

[0032] Reference Figure 2The present invention provides an automatic inspection method for an intrinsically safe power supply for mining, which uses an automatic detection device for intrinsically safe power supply for mining to automatically inspect key parameters of an intrinsically safe power supply 3 under test. The automatic detection device for intrinsically safe power supply for mining includes a power supply 9, a voltage regulating unit 11, an adjustable load unit 14, a current detection unit 15, a voltage detection unit, a display unit 18, a communication unit 16, a protection switching unit and a core control unit 17; the power supply 9 is connected to the voltage regulating unit 11, the voltage regulating unit 11 is connected to the core control unit 17, the adjustable load unit 14 is connected to the current detection unit 15, the adjustable load unit 14 and the current detection unit 15 are respectively connected to the core control unit 17, the display unit 18 and the communication unit 16 are respectively connected to the core control unit 17, the protection switching unit is connected to the core control unit 17, and the protection switching unit adopts a relay, which is used to be connected to the input end of the intrinsically safe power supply 3 under test, the connection point between the previous heavy protection output end and the next heavy protection input end, and the output end respectively;

[0033] The voltage detection unit includes a power supply voltage detection unit 10, an input voltage detection unit 12, and an output voltage detection unit 13. The power supply voltage detection unit 10 is connected to the power supply 9, the voltage adjustment unit 11, and the core control unit 17 respectively, and the power supply voltage detection unit 10 is used to detect the output voltage of the power supply; the input voltage detection unit 12 is connected to the voltage adjustment unit 11 and the core control unit 17 respectively, and the input voltage detection unit 12 is used to detect the input voltage output to the intrinsically safe power supply 3 under test after adjustment by the voltage adjustment unit 11, and the voltage adjustment unit 11 and the input voltage detection unit 12 are both used to be connected to the input end of the intrinsically safe power supply 3 under test; the output voltage detection unit 13 is connected to the adjustable load unit 14 and the core control unit 17 respectively, and the output voltage detection unit 13 is used to detect the output voltage of the intrinsically safe power supply 3 under test, and the adjustable load unit 14, the current detection unit 15 and the output voltage detection unit 13 are all used to be connected to the output end of the intrinsically safe power supply 3 under test.

[0034] The automatic inspection method for the intrinsically safe power supply for mining includes automatically inspecting the overvoltage protection value of the intrinsically safe power supply 3 under test: in the initial state, the core control unit 17 automatically controls the adjustable load unit 14 to disconnect, and adjusts the input voltage U of the intrinsically safe power supply 3 under test. i is the rated voltage of the intrinsically safe power supply; at this time, the overvoltage protection is not implemented, U i with U o Then the core control unit 17 automatically adjusts the duty cycle of the PWM pulse width modulation signal output by itself to control the input voltage U of the intrinsically safe power supply 3 under test i At the same time, the core control unit 17 intensively collects and caches the input voltage U of the intrinsically safe power supply 3 under test. i And output voltage U o; After the overvoltage protection is executed, the output voltage U o will drop rapidly to zero; when the core control unit 17 detects the output voltage U o Lower than input voltage U i When the input voltage U of the intrinsically safe power supply 3 is 80%, record the input voltage U of the intrinsically safe power supply 3 i The value is the overvoltage protection value of the intrinsically safe power supply 3 under test.

[0035] Automatically check the overcurrent protection value of the tested intrinsically safe power supply 3: In the initial state, the core control unit 17 automatically controls the adjustable load unit 14 to disconnect and adjusts the input voltage U of the tested intrinsically safe power supply 3 i is the rated voltage of the intrinsically safe power supply; at this time, the load current I o is zero, the input voltage U i With output voltage U o Then the core control unit 17 automatically adjusts the duty cycle of the PWM pulse width modulation signal output by itself to control the load current I of the intrinsically safe power supply 3 under test o At the same time, the core control unit 17 intensively collects and caches the load current I of the intrinsically safe power supply 3 under test. o And output voltage U o ; Load current I of the intrinsically safe power supply 3 under test o It will gradually increase from zero as the load is adjusted. At the same time, the output voltage U o will slowly decrease; after the overcurrent protection is executed, the load current I o will drop rapidly to zero, and at the same time the output voltage U o will also drop rapidly to zero; when the core control unit 17 detects the output voltage U o Lower than input voltage U i When the load current I of the intrinsically safe power supply 3 under test during this adjustment period is 50%, the acquisition and caching are stopped, and the load current I of the intrinsically safe power supply 3 under test during this adjustment period is filtered and recorded from the cached data. o The maximum value is the overcurrent protection value of the intrinsically safe power supply 3 under test.

[0036] Automatically check the maximum output voltage deviation value of the tested intrinsically safe power supply 3: In the initial state, the core control unit 17 automatically controls the adjustable load unit 14 to disconnect and adjusts the input voltage U of the tested intrinsically safe power supply 3 i The rated voltage of the intrinsically safe power supply is then automatically adjusted by the core control unit 17 to control the load current I of the intrinsically safe power supply 3 under test by adjusting the duty cycle of the PWM pulse width modulation signal output by itself. o At the same time, the core control unit 17 intensively collects and caches the load current I of the intrinsically safe power supply 3 under test.o 、Input voltage U i And output voltage U o ; Load current I of the intrinsically safe power supply 3 under test o It will gradually increase from zero as the load is adjusted. At the same time, the output voltage U o will slowly decrease; after the overcurrent protection is executed, the load current I o will drop rapidly to zero, and at the same time the output voltage U o will also drop rapidly to zero; when the core control unit 17 detects the output voltage U o Lower than input voltage U i When the load current I of the intrinsically safe power supply 3 under test during this adjustment period is 50%, the acquisition and caching are stopped, and the load current I of the intrinsically safe power supply 3 under test during this adjustment period is filtered and recorded from the cached data. o The input voltage U corresponding to the maximum value i And the output voltage U o The value of input voltage U i And the output voltage U o The difference is the maximum output voltage deviation value of the tested intrinsically safe power supply 3.

[0037] Automatically check the protection interval time of the tested intrinsically safe power supply 3: In the initial state, the core control unit 17 automatically controls the adjustable load unit 14 to disconnect and adjusts the input voltage U of the tested intrinsically safe power supply 3 i The rated voltage of the intrinsically safe power supply is then automatically adjusted by the core control unit 17 to control the load current I of the intrinsically safe power supply 3 under test by adjusting the duty cycle of the PWM pulse width modulation signal output by itself. o Increases until the overcurrent protection is executed, and the load current I o When it drops to zero, record the time as t 0 Keep the load unchanged, and then the core control unit 17 intensively collects the load current I of the intrinsically safe power supply 3 under test o , record the load current I of the intrinsically safe power supply 3 under test o The time when it rises and then drops to zero again is t 1 , t 0 to 1 The elapsed time is the protection interval time T of the intrinsically safe power supply 3 under test. 1 .

[0038] Automatically check the protection recovery process of the tested intrinsically safe power supply 3: In the initial state, the core control unit 17 automatically controls the adjustable load unit 14 to disconnect and adjusts the input voltage U of the tested intrinsically safe power supply 3 iThe load current I of the intrinsically safe power supply 3 under test is controlled by automatically adjusting the duty cycle of the PWM pulse width modulation signal output by the core control unit 17. o Increases until the overcurrent protection is executed, and the load current I o When the load current I of the intrinsically safe power supply 3 under test is reduced to zero, the load is kept unchanged, and then the core control unit 17 intensively collects the load current I o ; When the load current I o When rising from zero, record the time as t 2 At the same time, the core control unit 17 starts to intensively record the load current I of the intrinsically safe power supply 3 under test o until the load current I o When it drops to zero again, record the time as t 3 and stop recording I o ;t 2 to 3 The elapsed time is the recovery time of the tested intrinsically safe power supply 3. 2 , combined with the load current I of the intrinsically safe power supply 3 under test recorded during the period o The data reflects the protection recovery process of the tested intrinsically safe power supply 3.

[0039] In addition, the automatic inspection method for the intrinsically safe power supply for mining also includes automatically inspecting the voltage level of the intrinsically safe power supply 3 under test: the power supply voltage U P The voltage level of the intrinsically safe power supply 3 under test is collected and determined by the core control unit 17. P The range is: U P ≥26V, it is determined that the voltage level of the tested intrinsically safe power supply 3 is 24V. P The range is: 20V≤U P <26V, it is determined that the voltage level of the tested intrinsically safe power supply 3 is 18V. P The range is: 14V≤U P <20V, it is determined that the voltage level of the intrinsically safe power supply 3 under test is 12V. P The range is: U P <14V, it is determined that the intrinsically safe power supply 3 under test is faulty.

[0040] In addition, the automatic inspection method for intrinsically safe power supplies for mining also includes automatic inspection of the intrinsically safe power supply 3 under automatic switching of different heavy protection positions: in the initial state, the core control unit 17 automatically controls the relay to disconnect one level of protection of the intrinsically safe power supply 3 under test, so that the one level of protection takes effect, and at the same time short-circuits the remaining heavy protections to make the remaining heavy protections invalid; when the parameter inspection of the intrinsically safe power supply 3 under the one level of protection is completed, the core control unit 17 automatically controls the relay to short-circuit the one level of protection to make the one level of protection invalid, and at the same time disconnects any other uninspected protection to make any other protection take effect, and re-inspects the parameters of the intrinsically safe power supply 3 under test until the parameters of the intrinsically safe power supply 3 under all heavy protections are inspected.

[0041] Specifically, the voltage regulating unit 11 is connected between the output end of the power supply 9 and the input end of the intrinsically safe power supply 3 under test, and is connected to the core control unit 17. Its function is to adjust the input voltage of the intrinsically safe power supply 3 under test, and to check the overvoltage protection value of the intrinsically safe power supply 3 under test in combination with the output state of the intrinsically safe power supply 3 under test.

[0042] Specifically, the voltage regulating unit 11 performs variable step-down adjustment control through the PWM pulse width modulation signal output by the core control unit 17; during the adjustment process, the core control unit 17 only needs to automatically adjust the duty cycle of the output PWM signal to obtain a stable and continuously variable DC voltage, which is provided to the tested intrinsically safe power supply 3. Compared with the existing adjustable linear power supply, the control method of the PWM pulse width modulation signal can improve the power supply efficiency and reduce the heat generation of the automatic detection device for intrinsically safe power supply for mining.

[0043] Specifically, the adjustable load unit 14 is connected in series before the current detection unit 15 and then connected to the output end of the intrinsically safe power supply 3 under test, and is connected to the core control unit 17; its function is to adjust the output current of the intrinsically safe power supply 3 under test, and to check the overcurrent protection value of the intrinsically safe power supply 3 under test in combination with the output state of the intrinsically safe power supply 3 under test.

[0044] Specifically, the intrinsically safe power supply 3 under test is divided into multiple protection levels of ia, ib, and ic, which respectively allow the intrinsically safe power supply 3 under test to still have protection capabilities when two faults, one fault, and zero faults occur; correspondingly, there are triple, double, and single protections. When inspecting the intrinsically safe power supply 3 under test, it is necessary to simulate a corresponding number of faults according to the protection level, and test the remaining protective circuits. Relays or relay groups are used to realize arbitrary combination fault simulation, that is, short-circuit the input and output ends of any one or more protection circuits to make the protection invalid. The protection switching unit is used to connect the input end of the intrinsically safe power supply 3 under test, the connection point between the output end of the previous protection and the input end of the next protection, and the output end connection to realize fault simulation.

[0045] Specifically, the voltage detection unit includes a power supply voltage detection unit 10, an input voltage detection unit 12, and an output voltage detection unit 13; wherein the power supply voltage detection unit 10, the input voltage detection unit 12, and the output voltage detection unit 13 are respectively connected to the core control unit 17; the power supply voltage detected by the power supply voltage detection unit 10, the input voltage of the intrinsically safe power supply 3 under test detected by the input voltage detection unit 12, and the output voltage of the intrinsically safe power supply 3 under test detected by the output voltage detection unit 13 are collected through the ADC analog-to-digital conversion module inside the core control unit 17. The purpose of collecting the power supply voltage is to identify the voltage level of the intrinsically safe power supply 3 under test through the power supply voltage range, and to introduce the corresponding qualified threshold value of the corresponding voltage level; the purpose of collecting the input voltage of the intrinsically safe power supply 3 under test is to check the overvoltage protection value of the intrinsically safe power supply 3 under test in combination with the output state of the intrinsically safe power supply 3 under test; the purpose of collecting the output voltage of the intrinsically safe power supply 3 under test is to check the maximum output voltage deviation value of the intrinsically safe power supply 3 under test in combination with the input voltage of the intrinsically safe power supply 3 under test.

[0046] Specifically, the current detection unit 15 is connected in series to the adjustable load unit 14 and then to the output end of the intrinsically safe power supply 3 under test, and is connected to the core control unit 17; its function is to detect the output current of the intrinsically safe power supply 3 under test, and to check the overcurrent protection value of the intrinsically safe power supply 3 under test in combination with the output state of the intrinsically safe power supply 3 under test.

[0047] Specifically, the display unit 18 is connected to the core control unit 17 , and human-computer interaction is accomplished through the display unit 18 .

[0048] Specifically, the communication unit 16 is connected to the core control unit 17, and the communication unit 16 is also connected to the host computer, so that the data results of the key parameters of the tested intrinsically safe power supply 3 can be uploaded to the host computer through the communication unit 16 to complete the data interaction with the host computer.

[0049] In summary, the core control unit 17, as the core main control device of the automatic inspection method for intrinsically safe power supply for mining of the present invention, realizes the collection of current and voltage, the switching of protection, the automatic adjustment of the input voltage of the intrinsically safe power supply 3 under test, the automatic adjustment of the adjustable load of the intrinsically safe power supply 3 under test, the transmission of data and waveforms, and the communication with the host computer. The automatic inspection method for intrinsically safe power supply for mining of the present invention adopts a microcomputer system with PWM pulse width modulation signal output, ADC analog-to-digital conversion acquisition, and UART communication functions as the core control unit 17 to complete all the above functions. The core control unit 17 is connected to the voltage regulating unit 11, outputs a PWM pulse width modulation signal, and adjusts the input voltage of the intrinsically safe power supply 3 under test; the core control unit 17 is connected to the adjustable load unit 14, outputs a PWM pulse width modulation signal, and adjusts the output load current of the intrinsically safe power supply 3 under test; the core control unit 17 is connected to the protection switching unit, and outputs a switch signal to simulate a circuit fault; the core control unit 17 is connected to the voltage detection unit, and collects the power supply voltage, the input voltage of the intrinsically safe power supply 3 under test, and the output voltage of the intrinsically safe power supply 3 under test through the ADC analog-to-digital conversion module inside the core control unit 17; The control unit 17 is connected to the current detection unit 15 to detect the output current of the intrinsically safe power supply 3 under test, and checks the overcurrent protection value of the intrinsically safe power supply 3 under test in combination with the output state of the intrinsically safe power supply 3 under test; the core control unit 17 is connected to the display unit 18 to display the test parameters, recovery waveform and test results of the intrinsically safe power supply 3 under test through the display unit 18; the core control unit 17 is connected to the communication unit 16 to upload data to the host computer through the communication unit 16, and realize statistics, storage, printing and other functions on the host computer; the core control unit 17 formulates a corresponding process according to the automatic inspection method of the present invention to control the entire automatic inspection process of the present invention.

[0050] It can be understood that the above specific description of the present invention is only used to illustrate the present invention and is not limited to the technical solutions described in the embodiments of the present invention. Those skilled in the art should understand that the present invention can still be modified or replaced by equivalents to achieve the same technical effects; as long as the use requirements are met, they are within the protection scope of the present invention.

Claims

1. A method for automatically testing intrinsically safe power supplies for mining, characterized in that: The key parameters of the tested intrinsically safe power supply are automatically inspected by using an automatic detection device for intrinsically safe power supply for mining. The automatic detection device for intrinsically safe power supply for mining includes a power supply, a voltage regulating unit, an adjustable load unit, a current detection unit, a voltage detection unit, a display unit, a communication unit, a protection switching unit and a core control unit; the power supply is connected to the voltage regulating unit, the voltage regulating unit is connected to the core control unit, the adjustable load unit is connected to the current detection unit, the adjustable load unit and the current detection unit are respectively connected to the core control unit, the display unit and the communication unit are respectively connected to the core control unit, the protection switching unit is connected to the core control unit, the protection switching unit adopts a relay, and the relay is used to be connected to the input end of the tested intrinsically safe power supply, the connection point between the previous heavy protection output end and the next heavy protection input end, and the output end respectively; The voltage detection unit includes a power supply voltage detection unit, an input voltage detection unit, and an output voltage detection unit. The power supply voltage detection unit is respectively connected to the power supply, the voltage regulating unit, and the core control unit, and the power supply voltage detection unit is used to detect the output voltage of the power supply; the input voltage detection unit is respectively connected to the voltage regulating unit and the core control unit, and the input voltage detection unit is used to detect the input voltage output to the intrinsically safe power supply under test after adjustment by the voltage regulating unit, and the voltage regulating unit and the input voltage detection unit are both used to be connected to the input end of the intrinsically safe power supply under test; the output voltage detection unit is respectively connected to the adjustable load unit and the core control unit, and the output voltage detection unit is used to detect the output voltage of the intrinsically safe power supply under test, and the adjustable load unit, the current detection unit, and the output voltage detection unit are all used to be connected to the output end of the intrinsically safe power supply under test; The automatic inspection method for the intrinsically safe power supply for mining includes automatically inspecting the overvoltage protection value of the intrinsically safe power supply under test: in the initial state, the core control unit automatically controls the adjustable load unit to disconnect and adjusts the input voltage U of the intrinsically safe power supply under test. i is the rated voltage of the intrinsically safe power supply; then the core control unit automatically adjusts the duty cycle of the PWM pulse width modulation signal output by itself to control the input voltage U of the intrinsically safe power supply under test i At the same time, the core control unit intensively collects and caches the input voltage U of the intrinsically safe power supply under test. i And output voltage U o ; When the core control unit detects the output voltage U o Lower than input voltage U i When the input voltage U of the intrinsically safe power supply under test reaches 80%, record the input voltage U of the intrinsically safe power supply under test. i The value is the overvoltage protection value of the intrinsically safe power supply under test; Automatically check the overcurrent protection value of the tested intrinsically safe power supply: In the initial state, the core control unit automatically controls the adjustable load unit to disconnect and adjusts the input voltage U of the tested intrinsically safe power supply. i is the rated voltage of the intrinsically safe power supply; then the core control unit automatically adjusts the duty cycle of the PWM pulse width modulation signal output by itself to control the load current I of the intrinsically safe power supply under test o At the same time, the core control unit intensively collects and caches the load current I of the intrinsically safe power supply under test. o And output voltage U o ; When the core control unit detects the output voltage U o Lower than input voltage U i When the load current I of the intrinsically safe power supply under test during this adjustment period reaches 50%, the acquisition and caching are stopped, and the load current I of the intrinsically safe power supply under test during this adjustment period is filtered and recorded from the cached data. o The maximum value is the overcurrent protection value of the intrinsically safe power supply under test; Automatically check the maximum output voltage deviation value of the tested intrinsically safe power supply: In the initial state, the core control unit automatically controls the adjustable load unit to disconnect and adjusts the input voltage U of the tested intrinsically safe power supply. i is the rated voltage of the intrinsically safe power supply; then the core control unit automatically adjusts the duty cycle of the PWM pulse width modulation signal output by itself to control the load current I of the intrinsically safe power supply under test o At the same time, the core control unit intensively collects and caches the load current I of the intrinsically safe power supply under test. o 、Input voltage U i And output voltage U o ; When the core control unit detects the output voltage U o Lower than input voltage U i When the load current I of the intrinsically safe power supply under test during this adjustment period reaches 50%, the acquisition and caching are stopped, and the load current I of the intrinsically safe power supply under test during this adjustment period is filtered and recorded from the cached data. o The input voltage U corresponding to the maximum value i And the output voltage U o The value of input voltage U i And the output voltage U o The difference is the maximum output voltage deviation of the tested intrinsically safe power supply; Automatically check the protection interval time of the intrinsically safe power supply under test: In the initial state, the core control unit automatically controls the adjustable load unit to disconnect and adjusts the input voltage U of the intrinsically safe power supply under test. i is the rated voltage of the intrinsically safe power supply; then the core control unit automatically adjusts the duty cycle of the PWM pulse width modulation signal output by itself to control the load current I of the intrinsically safe power supply under test o Rising until the overcurrent protection is executed, the load current I o When it drops to zero, the time at this time is recorded as t0; the load is kept unchanged, and then the core control unit intensively collects the load current I of the intrinsically safe power supply under test o , record the load current I of the intrinsically safe power supply under test o The time when it drops to zero again after rising is t1, and the time from t0 to t1 is the protection interval time T1 of the intrinsically safe power supply under test; Automatically check the protection recovery process of the tested intrinsically safe power supply: In the initial state, the core control unit automatically controls the adjustable load unit to disconnect and adjusts the input voltage U of the tested intrinsically safe power supply. i is the rated voltage of the intrinsically safe power supply; the core control unit automatically adjusts the duty cycle of the PWM pulse width modulation signal output by itself to control the load current I of the intrinsically safe power supply under test o Rising until the overcurrent protection is executed, the load current I o When it drops to zero, the load is kept unchanged, and then the core control unit intensively collects the load current I of the intrinsically safe power supply under test. o ; When the load current I o When it starts to rise from zero, the time at this time is recorded as t2, and at the same time the core control unit starts to intensively record the load current I of the intrinsically safe power supply under test. o until the load current I of the intrinsically safe power supply under test o When it drops to zero again, record the time as t3 and stop recording I o The time from t2 to t3 is the recovery time T2 of the intrinsically safe power supply under test, combined with the load current I of the intrinsically safe power supply under test recorded during this period. o The data reflects the protection recovery process of the tested intrinsically safe power supply.

2. The method for automatically testing an intrinsically safe power supply for mining according to claim 1, characterized in that: The automatic inspection method for the intrinsically safe power supply for mining also includes automatically inspecting the voltage level of the intrinsically safe power supply under test: inspecting the power supply voltage U P The core control unit collects and determines the voltage level of the intrinsically safe power supply under test.

3. The method for automatically checking an intrinsically safe power supply for mining according to claim 2 is characterized in that: If the supply voltage U P The range is: U P ≥26V, it is determined that the voltage level of the tested intrinsically safe power supply is 24.

4. The method for automatically checking an intrinsically safe power supply for mining according to claim 2 is characterized in that: If the supply voltage U P The range is: 20V≤U P <26V, it is determined that the voltage level of the tested intrinsically safe power supply is 18V.

5. The method for automatically checking an intrinsically safe power supply for mining according to claim 2 is characterized in that: If the supply voltage U P The range is: 14V≤U P <20V, it is determined that the voltage level of the tested intrinsically safe power supply is 12V voltage level.

6. The method for automatically testing an intrinsically safe power supply for mining according to claim 2, characterized in that: If the supply voltage U P The range is: U P <14V, it is determined that the intrinsically safe power supply under test is faulty.

7. The method for automatically testing an intrinsically safe power supply for mining according to claim 1, characterized in that: The automatic inspection method for the intrinsically safe power supply for mining also includes automatically inspecting the intrinsically safe power supply under automatic switching of different heavy protection positions: in the initial state, the core control unit automatically controls the relay to disconnect one level of protection of the intrinsically safe power supply under test, so that the one level of protection takes effect, and short-circuit the remaining heavy protections at the same time, so that the remaining heavy protections fail; when the parameter inspection of the intrinsically safe power supply under the one level of protection is completed, the core control unit automatically controls the relay to short-circuit the one level of protection, so that the one level of protection fails, and disconnects any other uninspected protection at the same time, so that any other protection takes effect, and re-inspects the parameters of the intrinsically safe power supply under test until the parameters of the intrinsically safe power supply under all heavy protections are inspected.

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