Electronic load port open-circuit voltage surge suppression system and method

Abstract

The invention belongs to the field of voltage surge suppression, and particularly relates to an electronic load port open-circuit voltage surge suppression system and a voltage surge suppression method based on the system. The technical problems that an existing protection method is prone to false triggering, slow in protection onset time and poor in protection effect are mainly solved. The system comprises a load current given module, a load open circuit protection module, a load open circuit judgment module and a sampling module, the sampling end of the sampling module is connected with tested equipment, and the output end is connected with the input end of the load open circuit judgment module; the input end of the load open-circuit protection module is connected with the output end of the load open-circuit judgment module, and the output end is connected with the first input end of the load current given module; the second input end of the load current given module receives client given load parameters, and the output end of the load current given module is connected with tested equipment. According to the invention, given blocking can be carried out at the moment of open circuit of the load port, so that generation of port voltage spikes is avoided, and tested equipment is protected.

Description

TECHNICAL FIELD

[0001] The present application relates to a voltage surge suppression system and method, in particular to an electronic load port open circuit voltage surge suppression system and a voltage surge suppression method based on the system. BACKGROUND

[0002] In the use of traditional electronic load, most of the test content of the test product is the protection function, and the triggering of the protection function often causes the test product to cut off the power supply on the AC side to protect the equipment, and at this time the constant current property of the electronic load test platform itself will cause a voltage spike on the output side port of the electronic load due to the absence of the power grid, and the level of this spike voltage often exceeds the AC side voltage withstand of the test product, thus causing the AC side of the test product to be broken down, resulting in incalculable losses. Therefore, protection needs to be provided to the test product during testing to avoid the situation of the AC side of the test product being broken down.

[0003] The existing protection method is single voltage protection, which uses the sampled voltage value to make real-time judgment whether it exceeds the threshold value, thereby performing protection action, but this protection method has the following disadvantages:

[0004] 1. Easy to mis-trigger. Since there may be harmonics and sampling burrs in the voltage sampling waveform during power supply use, the single voltage protection may be frequently misjudged, resulting in protection mis-triggering.

[0005] 2. Slow protection activation time. Since the single voltage protection needs to be filtered for a period of time to avoid voltage sampling noise when used, it will cause a delay in judgment, thus missing the peak suppression time and causing protection failure.

[0006] 3. Poor protection effect. The protection process generally uses a direct blocking given form of processing, which makes it impossible to discharge the peak energy in the main circuit, thus resulting in poor protection effect. SUMMARY

[0007] The purpose of the present application is to solve the technical problems of existing protection methods that are prone to mis-triggering, slow protection activation time, and poor protection effect, and to provide an electronic load port open circuit voltage surge suppression system and method.

[0008] To achieve the above purpose, the technical solution adopted by the present application is:

[0009] An electronic load port open circuit voltage surge suppression system, characterized in that:

[0010] It comprises a load current given module, a load open circuit protection module, a load open circuit determination module, and a sampling module.

[0011] The sampling end of the sampling module is connected with the test equipment, and the output end is connected with the input end of the load open circuit judgment module, for obtaining current and voltage sampling signals and outputting to the load open circuit judgment module;

[0012] The load open circuit judgment module is used for calculating the current and voltage waveform peak value and the maximum waveform slope of the whole period at normal time as a judgment threshold value, and determining to enter the pre-protection state when the real-time waveform slope of the real-time current and voltage sampling signals exceeds the maximum waveform slope, and considering that the port appears open circuit when the real-time current and voltage both exceed the waveform peak value in the pre-protection state, so as to send an open circuit fault signal;

[0013] The input end of the load open circuit protection module is connected with the output end of the load open circuit judgment module, and the output end is connected with the first input end of the load current given module, for entering the protection inhibition state when receiving the open circuit fault signal, and sending a given blocking signal to the load current given module;

[0014] The second input end of the load current given module is used for receiving the customer given load parameter, and the output end is connected with the test equipment, and the load current given module is used for outputting the given load current to the test equipment according to the given load parameter at normal time, and clearing the given load parameter and outputting the protection threshold current to the test equipment when receiving the given blocking signal, so as to avoid the appearance of port voltage peak.

[0015] Further, the sampling module comprises a current sampling module and a voltage sampling module;

[0016] The sampling ends of the current sampling module and the voltage sampling module are respectively connected with the test equipment, and the output ends are respectively connected with the input end of the load open circuit judgment module;

[0017] The current sampling module is used for obtaining the current sampling signal and outputting to the load open circuit judgment module, and the voltage sampling module is used for obtaining the voltage sampling signal and outputting to the load open circuit judgment module.

[0018] Further, the output end of the load current given module is connected with the test equipment through a power module, and the power supply end of the power module is connected with an external power supply;

[0019] The power module is used for outputting the given load current after power amplification to the test equipment.

[0020] Further, the power supply end of the power module is connected with an external AC power supply.

[0021] Meanwhile, the application also provides an electronic load port open circuit voltage impact inhibition method based on the electronic load port open circuit voltage impact inhibition system, and the speciality thereof is that:

[0022] Step 1, the sampling end of the sampling module and the output end of the load current given module are connected with the test equipment respectively;

[0023] Step 2, the corresponding given load current is output to the test equipment by the load current given module according to the customer given load parameter;

[0024] Step 3, the test equipment is sampled in real time by the sampling module, current and voltage sampling signals are obtained and output to the load open circuit determination module;

[0025] Step 4, the current and voltage waveform peak values and the maximum waveform slope at normal time are calculated as judgment threshold values by the load open circuit determination module according to the current and voltage sampling signals, when the real-time waveform slope of the real-time current and voltage sampling signals is detected to be all greater than the maximum waveform slope, it is determined that the pre-protection state is entered, when the real-time current and voltage are detected to be all greater than the waveform peak value in the pre-protection state, it is considered that the port is open, so that an open circuit fault signal is sent out, and step 5 is executed, when the real-time waveform slope of the real-time current or voltage sampling signal is detected to be not greater than the maximum waveform slope, step 3 is returned;

[0026] Step 5, the load open circuit protection module enters the protection inhibition state when the open circuit fault signal is received, and sends a given blocking signal to the load current given module;

[0027] Step 6, the load current given module clears the customer given load parameter when the given blocking signal is received, and outputs a protection threshold current to the test equipment, so as to avoid the generation of port voltage spikes.

[0028] The beneficial effects of the present application are:

[0029] 1, the present application can sample the voltage and current of the main loop in real time, the open circuit characteristic is judged in the load open circuit determination module, and the judgment result is sent to the open circuit protection module, so that the given blocking can be performed at the moment of the load port open circuit, the delay is short, and the generation of port voltage spikes can be avoided in time to protect the test equipment.

[0030] 2, the present application uses the feature judgment scheme and does not increase the hardware, can be embedded in the original control system, and does not have obvious cost increase, solves the technical problem of the original electronic load that the impact voltage appears at the port open circuit under the constant current characteristic.

[0031] 3, the present application takes current and voltage as judgment threshold values, when single current or voltage glitches appear, false triggering does not occur, and the reliability is higher.

[0032] 4, when the given blocking is performed, the output of the load current given module is switched to the protection threshold current, so that the peak energy in the main loop can be discharged, and the protection effect is improved. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 is a structural schematic diagram of an embodiment of an open-circuit voltage surge suppression system of an electronic load port of the present application;

[0034] Figure 2 is a structural schematic diagram of the connection of an open-circuit voltage surge suppression system of the present application and a test device;

[0035] Figure 3 is a device structure connection diagram of an embodiment of an open-circuit voltage surge suppression system of the present application;

[0036] Figure 4 is a flowchart of an embodiment of an open-circuit voltage surge suppression method of the present application. DETAILED DESCRIPTION

[0037] In order to make the purpose, advantages and characteristics of the present application clearer, a kind of electronic load port open-circuit voltage surge suppression system and method proposed by the present application is further detailed below in conjunction with drawings and specific embodiments. The advantages and characteristics of the present application will be clearer according to the following specific embodiments.

[0038] Referring to Figure 1 and Figure 3 , the embodiment of the present application is an electronic load port open-circuit voltage surge suppression system, mainly including an electronic load composed of load current setting module, load open-circuit protection module, load open-circuit determination module, current sampling module, voltage sampling module and power module.

[0039] Among them, load current setting module, load open-circuit protection module and load open-circuit determination module are software modules, which are carried on FPGA, so as to utilize the high-speed operation characteristics of FPGA to improve the real-time performance of protection. Current sampling module, voltage sampling module and power module are circuit modules, and the connection between circuit modules and FPGA is all high-speed optical fiber, which utilizes the high-speed communication characteristics of high-speed optical fiber to further improve the real-time performance of protection. The specific circuit of the circuit module can refer to the existing design, which can achieve the purpose of the embodiment and meet the test needs, and in the embodiment, the specific circuit structure is not specifically introduced.

[0040] The sampling ends of current sampling module and voltage sampling module are respectively connected with the test device, and the output ends are respectively connected with the input ends of load open-circuit determination module. Current sampling module can sample the current of test device to obtain current sampling signal. Voltage sampling module can sample the voltage of test device to obtain voltage sampling signal. Current sampling module and voltage sampling module output the obtained current sampling signal and voltage sampling signal as input data of load open-circuit determination module to load open-circuit determination module.

[0041] The load open circuit determination module determines the threshold value by calculating the peak value of the current and voltage waveform and the maximum waveform slope of the whole period according to the current sampling signal and the voltage sampling signal sent by the current sampling module and the voltage sampling module. When the real-time waveform slope of the real-time current and voltage sampling signal detected by the load open circuit determination module exceeds the maximum waveform slope, the load open circuit determination module determines that the pre-protection state is entered, and when the real-time current and voltage detected in the pre-protection state exceed the waveform peak value, it is determined that the port is open, and an open circuit fault signal is sent.

[0042] The input end of the load open circuit protection module is connected with the output end of the load open circuit determination module, and the output end is connected with the first input end of the load current setting module. When the load open circuit protection module receives the open circuit fault signal, it enters the protection inhibition state and sends a given blocking signal to the load current setting module.

[0043] The second input end of the load current setting module receives the given load parameters of the customer, and the output end is connected with the input end of the power module. The output end of the power module is connected with the test equipment, and the power supply end is connected with the external AC power supply. The load current setting module outputs the given load current to the power module according to the given load parameters at normal time, and the power module outputs the given load current to the test equipment after power amplification, so as to realize the test function. When the load current setting module receives the given blocking signal, it will instantaneously clear the given load parameters, switch the original given load current to the protection threshold current, and output the protection threshold current to the test equipment through the power module to avoid the occurrence of port voltage peak, and at the same time, the peak energy is released smoothly.

[0044] In specific application, the inhibition device of the embodiment can continuously sample high-speed voltage and current and make real-time open circuit judgment to obtain real-time open circuit state, and can lock the given port to avoid the occurrence of peak voltage within a short time after the occurrence of open circuit, so as to effectively protect the test equipment.

[0045] The inhibition method based on the above inhibition system specifically includes the following steps:

[0046] Step 1, connect the sampling end of the sampling module and the output end of the load current setting module with the test equipment respectively.

[0047] Step 2, output the corresponding given load current to the test equipment through the load current setting module according to the given load parameters of the customer.

[0048] Step 3, real-time sampling of the test equipment is performed through the sampling module to obtain current and voltage sampling signals and output them to the load open circuit determination module.

[0049] Step 4, according to the current and voltage sampling signals, the load open circuit judgment module calculates the current and voltage waveform peak value at normal time and the maximum waveform slope of the whole cycle as the judgment threshold. When it is detected that the real-time waveform slope of the real-time current and voltage sampling signals exceeds the maximum waveform slope, it is determined that the pre-protection state is entered. When it is detected that the real-time current and voltage exceeds the waveform peak value in the pre-protection state, it is considered that the port appears open circuit, so as to send an open circuit fault signal, and step 5 is executed; when it is detected that the real-time waveform slope of the real-time current or voltage sampling signal does not exceed the maximum waveform slope, return to step 3.

[0050] Step 5, the load open circuit protection module enters the protection inhibition state when receiving the open circuit fault signal, and sends a given blocking signal to the load current given module.

[0051] Step 6, the load current given module clears the customer given load parameter when receiving the given blocking signal, and outputs the protection threshold current to the test device to avoid the occurrence of port voltage peak.

[0052] In one embodiment, the test device is an alternating current power supply, and its rated parameters are: output voltage 220V, load current 500A. The suppression device of the embodiment is used for testing, and the specific test steps are as follows: Figure 4

[0053] Step 1, referring to Figure 2 , the sampling ends of the voltage sampling module and the current voltage module are connected with the alternating current power supply respectively to form a sampling loop; at the same time, the output end of the power module is connected with the alternating current power supply to form a main loop, realizing the connection of the electronic load and the test device.

[0054] Step 2, according to the customer given load parameter, the load current given module outputs the corresponding given load current to the alternating current power supply. In some embodiments, the customer given load parameter can be the rated parameter of the alternating current power supply, or can be appropriately increased or decreased on the basis of the rated parameter to test different working conditions of the alternating current power supply. As for the specific increase or decrease value, it is not described in detail in the embodiment, and can be executed according to the actual test needs.

[0055] Step 3, the voltage sampling module and the current voltage module sample the working voltage and current of the alternating current power supply in real time according to the frequency of sampling once per microsecond, so as to obtain the current sampling signal and the voltage sampling signal, and output them to the two input ends of the load open circuit judgment module respectively.

[0056] ​Step 4, the load open circuit determination module obtains the corresponding instantaneous waveform slope by subtracting the two adjacent current sampling signals and voltage sampling signals in time, and then obtains the maximum slope in 1 second as the slope threshold, and the actual calculated waveform slope threshold in this embodiment is 3000; it should be noted that the 1 second here is only a preferred embodiment of this embodiment, and in other embodiments of the application, the skilled in the art can set the precision according to the needs, as long as it meets the requirement of being much larger than the sampled waveform period, such as 0.5 seconds, 2 seconds, etc. Then the waveform slope is compared with the threshold in the output to determine whether to enter the pre-protection state.

[0057] When the real-time waveform slope of the real-time current and voltage sampling signals is detected to be greater than the maximum waveform slope, the pre-protection state is determined to be entered, for example, in this embodiment, the open circuit instantaneous slope value is detected to be 3824, which is greater than 3000, so the pre-protection state is determined to be entered. When the real-time waveform slope of the real-time current or voltage sampling signal is detected to be less than the maximum waveform slope, for example, in this embodiment, the open circuit instantaneous slope value is detected to be 2700, which is less than 3000, then return to step 3, thereby forming a closed loop monitoring.

[0058] When the pre-protection state is entered, it is also necessary to detect whether the real-time current and voltage of the alternating power source are both greater than the waveform peak value in the pre-protection state, if yes, it is considered that the port is open, so as to send an open circuit fault signal, and step 5 is executed; if not, it continues to be in the pre-protection state until the set time is reached and automatically exits, and the protection time set in this embodiment is 480us. Of course, in other embodiments of the application, the skilled in the art can set the time according to the needs, which can be slightly longer or shorter, such as 300us, 600us, etc.

[0059] Step 5, the load open circuit protection module enters the protection inhibition state when receiving the open circuit fault signal, and sends a given blocking signal to the load current given module.

[0060] Step 6, the load current given module clears the customer given load parameters when receiving the given blocking signal, and outputs the protection threshold current to the test device, in this embodiment, the time from entering the pre-protection state to triggering the protection is 80us, which meets the protection requirement, so that the port voltage peak can be avoided in time, thereby avoiding the damage caused by the over-voltage impact on the alternating side of the test device due to the port voltage peak, and further avoiding the damage caused by the over-voltage impact on the alternating side of the test device due to the over-voltage impact on the alternating side of the test device.

Claims

1. An electronic load port open circuit voltage surge suppression system, characterized by: It includes a load current setting module, a load open circuit protection module, a load open circuit judgment module and a sampling module; The sampling end of the sampling module is connected to the device under test, and the output end is connected to the input end of the load open circuit determination module, for obtaining current and voltage sampling signals and outputting them to the load open circuit determination module; The load open circuit determination module is used to calculate the current and voltage waveform peak values ​​at normal times and the maximum waveform slope of the entire cycle based on the current and voltage sampling signals as a judgment threshold. When it is detected that the real-time waveform slopes of the real-time current and voltage sampling signals exceed the maximum waveform slope, it is determined to enter the pre-protection state. In the pre-protection state, if it is detected that the real-time current and voltage exceed the waveform peak values, it is considered that the port is open circuit, and an open circuit fault signal is issued; The input end of the load open circuit protection module is connected to the output end of the load open circuit determination module, and the output end is connected to the first input end of the load current setting module, and is used to enter a protection inhibition state when receiving an open circuit fault signal and send a given blocking signal to the load current setting module; The second input end of the load current setting module is used to receive the load parameters given by the customer, and the output end is connected to the test device. The load current setting module is used to output the given load current to the test device according to the given load parameters at normal times; when receiving the given blocking signal, the given load parameters are cleared and the protection threshold current is output to the test device to avoid port voltage spikes.

2. The electronic load port open circuit voltage surge suppression system according to claim 1, characterized in that: The sampling module includes a current sampling module and a voltage sampling module; The sampling terminals of the current sampling module and the voltage sampling module are respectively connected to the tested equipment, and the output terminals are respectively connected to the input terminals of the load open circuit determination module; The current sampling module is used to obtain a current sampling signal and output it to the load open circuit determination module, and the voltage sampling module is used to obtain a voltage sampling signal and output it to the load open circuit determination module.

3. The electronic load port open circuit voltage surge suppression system according to claim 1 or 2, characterized in that: The output end of the load current setting module is connected to the test device through the power module, and the power supply end of the power module is connected to an external power supply; The power module is used to amplify the power of a given load current and output it to the device under test.

4. The electronic load port open circuit voltage surge suppression system according to claim 3, characterized in that: The power supply end of the power module is connected to an external AC power source.

5. A method for suppressing open-circuit voltage surges at electronic load ports, based on a system for suppressing open-circuit voltage surges at electronic load ports according to any one of claims 1 to 4, characterized in that: The following steps are involved: Step 1: Connect the sampling terminal of the sampling module and the output terminal of the load current setting module to the device under test respectively; Step 2: Output the corresponding given load current to the device under test according to the customer's given load parameters through the load current setting module; Step 3: The sampling module performs real-time sampling on the device under test, obtains current and voltage sampling signals, and outputs them to the load open circuit determination module; Step 4: The load open circuit determination module calculates the peak current and voltage waveforms at normal times and the maximum waveform slope of the entire cycle based on the current and voltage sampling signals as a judgment threshold. When it is detected that the real-time waveform slopes of the real-time current and voltage sampling signals exceed the maximum waveform slope, it is determined to enter the pre-protection state. If it is detected that the real-time current and voltage exceed the waveform peaks in the pre-protection state, it is considered that the port is open circuit, and an open circuit fault signal is issued, and step 5 is executed. If it is detected that the real-time waveform slope of the real-time current or voltage sampling signal does not exceed the maximum waveform slope, the module returns to step 3. Step 5: When receiving the open circuit fault signal, the load open circuit protection module enters the protection inhibition state and sends a given blocking signal to the load current setting module; Step 6: When the load current setting module receives the given blocking signal, it clears the customer-given load parameters and outputs the protection threshold current to the device under test to avoid port voltage spikes.

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