Railway substation low-voltage side power-on detection method and detection device

Abstract

The application discloses a kind of railway substation low-voltage side power-on detection methods, comprising: the initial voltage of three-phase ac power supply of railway substation incoming line side is boosted to preset high voltage and output to the front end of incoming line side load;Collect the current, voltage and phase signal of voltage transformer and / or current transformer on the substation load after boosting and display;According to the comparison of the current, voltage signal value and preset signal value, obtain the detection result, display alarm information and shut down output when higher than preset signal value;Wherein, preset high voltage is to ensure that the current, voltage and phase signal can be collected on the side when preset high voltage is applied on high-voltage side under the condition that railway substation transformer low-voltage side short circuit occurs.This method boosts lower initial voltage, and the current of transformer low-voltage side is proportionally increased, which overcomes the problems such as small short-circuit impedance of transformer and large sampling device zero drift of mutual inductor, so that the measurement data meets the sampling accuracy requirement of protection device.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of railway power testing, and more particularly to a railway substation low-voltage side power-on detection method and detection equipment. BACKGROUND

[0002] The substation is a kind of power facility in the power system for functions such as voltage and current regulation, system protection, and power flow control, which is mainly composed of transformers, transformers, circuit breakers, series capacitor compensation devices, shunt reactors, etc. The construction process of the substation mainly includes foundation construction, equipment installation, primary cable laying and cable head manufacturing and installation (soft bus manufacturing and installation), secondary cable laying and wiring, equipment single debugging, equipment commissioning, and power transmission opening and commissioning. The equipment commissioning is particularly important for the construction quality of the substation, which is related to the equipment installation quality, the primary cable installation quality, the secondary cable wiring quality, and the final verification of the functions of each device and the implementation of the design functions, and to a considerable extent, it is also related to the power transmission success rate of the power system. Therefore, the power supply project needs to check and verify the equipment installation quality, cable wiring quality and various protection functions before power transmission. However, due to the numerous connections between devices in the substation system and the non-uniform configuration and logic relationship of protection devices between devices in each project, the system commissioning period and quality are significantly affected by the professional quality of the commissioning personnel, making it difficult to effectively control the commissioning period.

[0003] The secondary wiring loop detection operation mainly includes remote signaling loop, remote control loop and remote measurement loop detection. The voltage / current loop in the remote measurement loop is particularly important. If the wiring error is not checked out during the debugging and detection process, the protection device may malfunction or not act during power transmission, or even burn out the equipment. Therefore, the wiring polarity check of the transformer in the railway substation before power transmission is crucial. The conventional detection method is to use a pointer-type multimeter to check whether the current transformer polarity meets the design requirements and whether the voltage transformer is one-point grounded. Among them, the check of the transformer differential protection coil polarity, the feeder side current transformer polarity and the voltage transformer secondary coil wiring polarity is the most critical. The installation quality and wiring quality of these three devices directly affect the success of the power transmission and the reliability of the protection device action, that is, the wiring error of the transformer differential protection coil polarity will cause the transformer differential protection to malfunction, resulting in unsuccessful power transmission; the wiring error of the feeder side voltage and current loop will reduce the sensitivity of the impedance protection or distance protection in the feeder protection device or cause the possibility of refusal / malfunction during the feeder power transmission process or after the power transmission.

[0004] Before receiving power, railway substations conduct simulated power-on testing on the entire substation as required. The purpose is twofold: first, to determine the integrity and correctness of the primary wiring; and second, to verify that the secondary wiring and equipment meet the conditions for receiving power or are in a energized state as required. The core of this verification is whether the primary and secondary wiring meet the requirements of the protection device manuals or design, whether the sampling of each protection device is correct, whether each electrical interlocking circuit is complete and functional, and whether secondary equipment such as circuit breakers, device activation / deactivation, and setting values ​​meet the power-on requirements. Its function is to simulate energization before receiving power, serving as the final system test for formal power reception. The conventional practice is to tabulate and checklist the inspection items according to the equipment configuration of each substation, and then check each item one by one. Generally, a substation needs to be divided into three inspection teams: a primary equipment inspection team, a secondary wiring inspection team, and a relay protection inspection team. Each team has 4 people, totaling 12 people, and the inspection takes 3-5 days to complete. This method is inefficient, requires highly skilled inspectors, and is fragmented and unsystematic, resulting in long commissioning and testing cycles and significant resource investment. More notably, conventional power-on testing methods often fail to detect or acquire signals such as current, voltage, and phase, especially in cases of short circuits on the low-voltage side of transformers in railway substations. In these situations, current, voltage, and phase signals are frequently unavailable on the high-voltage side, making power-on testing impossible. Furthermore, when the transformer impedance is low and / or the high-to-low voltage turns ratio is large, it is often difficult to detect current, voltage, and phase signals, resulting in sampling accuracy that often fails to meet the requirements of power-on testing. Summary of the Invention

[0005] To address at least one deficiency or improvement requirement in existing technologies, this invention provides a method and equipment for detecting the energization of the low-voltage side of a railway substation. This overcomes the technical limitation that, in the event of a short circuit on the low-voltage side of a railway substation transformer, signals such as current, voltage, and phase are often unavailable on the high-voltage side, making energization testing frequently impossible. Simultaneously, it improves the efficiency of energization testing by overcoming the low testing efficiency caused by the need for individual equipment adjustments in traditional methods.

[0006] To achieve the above objectives, in a first aspect, the present invention provides a method for detecting the energization of the low-voltage side of a railway substation, comprising:

[0007] The initial voltage of the three-phase AC power supply on the incoming side of the railway substation is boosted to a preset high voltage;

[0008] The preset high voltage is output to the front end of the load on the incoming line side of the railway substation to energize the load;

[0009] Collect the current, voltage, and phase signals of the voltage transformers and / or current transformers on the substation load after the voltage is stepped up;

[0010] The signal value collected is displayed, a detection result is obtained according to comparison of the collected current and voltage signal values with preset signal values, and alarm information is displayed and the output is turned off when the preset signal values are exceeded;

[0011] The preset high voltage can ensure that the current, voltage and phase signals can be collected at the high-voltage side when the preset high voltage is applied to the high-voltage side in the case of low-voltage side short circuit of the transformer of the railway substation.

[0012] Further, the preset high voltage ranges from 380 to 1180 V.

[0013] Further, the preset high voltage is 1180 V.

[0014] Further, when the current, voltage and phase signals of the voltage transformer and / or current transformer on the load of the substation after voltage boosting are collected, the collected current, voltage and phase signal values and corresponding hexagon diagrams are displayed.

[0015] Further, the process of boosting the initial voltage to the preset high voltage comprises:

[0016] The preset high voltage is set to the single-chip microcomputer control board.

[0017] After the single-chip microcomputer control board receives the preset high voltage, the preset high voltage is stored in a register, and the output table header voltage value is collected and obtained.

[0018] When the output table header voltage value is less than the preset high voltage, the frequency converter is started by using 485 communication, and the input and output contactors are closed, so that the three-phase motor voltage regulator is boosted to the preset high voltage.

[0019] Further, after the initial voltage is boosted to the preset high voltage, the process further comprises:

[0020] When the output table header voltage value is equal to the preset high voltage, the frequency converter is turned off, so that the preset high voltage is stably output.

[0021] Further, the preset signal value is a preset signal value range or a preset signal single-point value; and the preset signal value is input through a data display device.

[0022] In a second aspect, the present application provides a low-voltage side power-on detection device for a railway substation, comprising a boosting module, a collecting module and a display module.

[0023] The boosting module is used for boosting the initial voltage of the three-phase alternating current power supply at the incoming line side of the railway substation to a preset high voltage, and outputting the preset high voltage to the front end of the load at the incoming line side of the railway substation, so as to power on the load.

[0024] The collecting module is configured to collect current, voltage and phase signals of a voltage transformer and / or a current transformer on the boosted substation load;

[0025] The display module is configured to display the collected signal values, input a preset signal value, and display an alarm information when the signal value is higher than the preset signal value.

[0026] Further, the safety protection module is further included.

[0027] The safety protection module includes one or more circuit protection mechanisms such as overvoltage protection, overcurrent protection, overload protection, short circuit protection and meter head fault alarm protection, and performs fault alarm and cuts off output when a fault occurs.

[0028] Further, the preset high voltage output is adjustable, and the voltage adjustment range is 380-1180V.

[0029] Overall, compared with the prior art, the above technical solutions conceived by the present application can achieve the following beneficial effects:

[0030] (1) The method of the present application raises the conventional lower initial voltage input at the incoming line side of the railway substation to a preset high voltage, thereby proportionally raising the current at the low voltage side of the transformer, meeting the requirement of applying voltage at the high voltage side in the case of short circuit at the low voltage side of the railway substation transformer, so that the current, voltage and phase can be collected at the high voltage side, thereby overcoming the problems of zero drift of the sampling device caused by small short circuit impedance of the transformer and large transformer ratio, and meeting the sampling accuracy requirement of the protection device. The setting of collecting and displaying various circuit signals and displaying alarm information and shutting down output when the signal value is higher than the preset signal value changes the low detection efficiency caused by the one-by-one debugging of the equipment in the traditional method, and improves the convenience and efficiency of the power-on detection method.

[0031] (2) The method of the present application is based on the output of the adjustable preset high voltage, which can adapt to the device configuration of various railway substations, increase the application range of the power-on detection method, and improve the convenience and efficiency of the power-on detection. Further preferably, the conventional lower initial voltage input at the incoming line side of the railway substation is raised to a preset high voltage of 1180V, thereby overcoming the defects of signal sampling as described above, meeting the requirement of power-on at the low voltage side of the subway DC power supply system, thereby increasing the application scenarios of the power-on detection method, and enabling the power-on detection work before power transmission of the railway and subway to be smoothly carried out.

[0032] (3) The adjustable voltage boosting module of the power-on detection device of the present invention can raise the conventionally input low initial voltage to a preset high voltage, and then output the preset high voltage to the front end of the current transformer on the incoming side of the railway substation. This can proportionally increase the current on the low-voltage side of the transformer, so that when the low-voltage side of the transformer in the railway substation is short-circuited, voltage can be applied to the high-voltage side, so that current, voltage and phase signals can be collected on the high-voltage side. This can overcome the problems of low short-circuit impedance of the transformer and zero drift of the sampling device due to the large transformer ratio, and make the measurement data meet the sampling accuracy requirements of the protection device.

[0033] (4) Through the integrated design of the data display device configuration and display design and the safety mechanism of the safety protection device, it is possible to collect and display various circuit signals at the same time and display alarm information and shut down the output when the signal value is higher than the preset value. This changes the situation of low detection efficiency caused by the equipment being debugged one by one in the traditional method, thereby improving the convenience and efficiency of power-on detection. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 A flowchart illustrating a method for detecting the energization of the low-voltage side of a railway substation, provided in an embodiment of this application;

[0036] Figure 2 A schematic block diagram of the module structure of a low-voltage side power-on detection device for a railway substation, provided in an embodiment of this application;

[0037] Figure 3 A schematic block diagram illustrating the structure and interface connection of a low-voltage side power-on detection device for a railway substation, provided as an embodiment of this application;

[0038] Figure 4 Wiring diagram of the meter input interface of the operation control cabinet provided in the embodiments of this application. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0040] Through a large number of energized detection test practices, the inventor found that the conventional energized detection method often cannot detect or collect current, voltage and phase signals, especially in the case of short circuit at the low voltage side of the transformer of the railway substation, and often cannot collect current, voltage and phase signals at the high voltage side of the transformer, which makes the energized detection test often cannot be normally implemented. In addition, when the transformer impedance is small and / or the transformer high-low voltage side ratio is large, it is often difficult to detect current, voltage and phase signals, thereby the sampling accuracy of the signals often cannot meet the requirements of the energized detection. Based on the current technical situation, through a large number of energized detection tests, it is found that by appropriately increasing the voltage of the three-phase alternating current input at the incoming line side of the railway substation, current, voltage and phase signals can be collected at the high voltage side of the transformer even in the case of short circuit at the low voltage side of the transformer of the railway substation, thereby solving the technical difficulty of signal collection. It is worth noting that during the energized detection, generally based on safety and economic considerations, the voltage at the incoming line side of the railway substation is often reduced, and the energized detection method of the present application reverses this conventional cognition. Through a large number of practices, it is found that the voltage at the incoming line side of the railway substation is boosted, and the boosted voltage is connected to the front end of the mutual inductor at the incoming line side of the railway substation. A voltage and current primary loop path is formed between the incoming line side voltage mutual inductor, the incoming line side current mutual inductor, the transformer, the transformer low voltage side current mutual inductor, the transformer low voltage side voltage mutual inductor and the ground. After the loop is formed, the current and voltage sampling conditions are checked at the control signal screen and the differential current and braking current values of the transformer main protection device are judged to see whether they meet the requirements of the protection device manual. The voltage is boosted to a preset high voltage to proportionally increase the current at the low voltage side of the transformer, thereby overcoming the technical defect that the current, voltage and phase signals cannot be collected at the high voltage side of the transformer in the case of short circuit at the low voltage side of the transformer of the railway substation, which makes the energized detection test often cannot be normally implemented. It also overcomes the problem of zero drift of the sampling device caused by small short-circuit impedance of the transformer and large mutual inductor ratio, so that the measurement data meets the sampling accuracy requirements of the protection device.

[0041] As shown in Figure 1 , in one embodiment, a railway substation low voltage side energized detection method mainly includes the following steps.

[0042] Step 1, the initial voltage of the three-phase AC power supply at the incoming side of the railway substation is boosted to a preset high voltage. The preset high voltage is a voltage that can ensure that the current, voltage and phase signals can be collected at the high-voltage side when the preset high voltage is applied at the high-voltage side under the condition that the low-voltage side of the railway substation transformer is short-circuited. The core purpose of the power-on detection method is to meet the condition that the high-voltage side is powered to the preset high voltage under the condition that the low-voltage side of the railway substation transformer is short-circuited, so that the high-voltage side protection device can collect current, voltage and phase and automatically record relevant data to display a hexagon diagram.

[0043] Preferably, the preset high voltage ranges from 380 to 1180V, and the voltage value of the conventional input at the incoming side of the railway substation is 380V. Therefore, the lower limit of the preset high voltage is 380V, and the upper limit is set to 1180V based on the comprehensive consideration of adapting to the power-on of the low-voltage side of the subway DC power supply system and meeting the signal collection described above. More preferably, the preset high voltage is set to 1180V, thereby overcoming problems such as zero drift of the sampling device caused by small short-circuit impedance of the transformer and large transformer ratio, meeting the sampling accuracy requirements of the protection device, and meeting the requirements of the power-on of the low-voltage side of the subway DC power supply system, thereby increasing the application scenarios of the power-on detection method and enabling the power-on detection work of the railway and the subway to be successfully carried out before power transmission.

[0044] Step 2, output the preset high voltage to the front end of the load at the incoming side of the railway substation to power on the load. The load is an electronic component connected in a circuit with a certain potential difference between two ends, such as a voltage transformer, a current transformer, a resistor, etc.

[0045] Step 3, collect the current, voltage and phase signals of the voltage transformer and / or current transformer on the boosted substation load.

[0046] Step 4, display the collected signal values, obtain the detection result according to the comparison of the collected current and voltage signal values with the preset signal values, and display an alarm information and shut down the output when the signal values are higher than the preset signal values.

[0047] The preset signal value is a preset signal value range or a single point value of a certain preset signal, which can be input to the data display device.

[0048] The set voltage value is input to the single-chip microcomputer control board on the data display device such as a display screen by using the automatic voltage regulation function. The single-chip microcomputer control board stores the voltage value in the register after receiving the voltage value and reads the output table head voltage value.

[0049] If the current voltage value is less than the set voltage value, the frequency converter is started by using 485 communication, and the input and output contactor is closed. At this time, the three-phase electric voltage regulator boosts the voltage.

[0050] When the table head voltage value is equal to the set voltage value, the frequency converter is turned off, and the output is stabilized at this time.

[0051] The single-chip microcomputer control board compares the real-time collected signal value with the set value, and displays an alarm information on the display screen and turns off the output if the signal value is higher than the set value.

[0052] Reference Figure 2 and Figure 3 In one embodiment, a railway substation low-voltage side power-on detection device mainly includes a boost module, an acquisition module, and a display module. The power-on detection device can be designed in a box shape, and the modules can be integrated in the box-shaped power-on detection device. The modules can be connected to each other or externally connected through a series of interfaces provided on the surface of the box-shaped power-on detection device.

[0053] The boost module is a circuit device with a boost function. The input end of the boost module can be connected to the three-phase AC power supply on the incoming line side of the railway substation through the power socket (power socket interface) on the surface of the box. The output end of the boost module can be connected to the load on the incoming line side of the railway substation through the power box output interface on the surface of the box, as shown in the figure. The boost module is used to boost the initial voltage of the three-phase AC power supply on the incoming line side of the railway substation to a preset high voltage, and output the preset high voltage to the front end of the load on the incoming line side of the railway substation to power on the load. Figure 3

[0054] The acquisition module is a circuit device with a signal acquisition function, which can simultaneously acquire multiple circuit signals. The input end of the acquisition module can be connected to the current, voltage, and phase signals of the voltage transformer and / or current transformer on the boosted substation load through the load feedback input interface on the surface of the box, and the acquired circuit signals can be transmitted to the display module for display. The acquisition module is used to acquire the current, voltage, and phase signals of the voltage transformer and / or current transformer on the boosted substation load.

[0055] The display module is a circuit device with display and / or input functions, which is used to display the signal values acquired by the acquisition module, input the preset signal values, and display an alarm information when the acquired signal values are higher than the preset signal values.

[0056] Preferably, the railway substation low-voltage side power-on detection device further includes a safety protection module.

[0057] The safety protection module is a circuit device with a circuit safety protection function, which includes one or more circuit protection mechanisms such as overvoltage protection, overcurrent protection, overload protection, short circuit protection, and table head fault alarm protection. When a fault occurs, the safety protection module will alarm and cut off the output.

[0058] ​Preferably, the output preset high voltage is adjustable, and the voltage adjustment range is 0-1180V; more preferably, the voltage adjustment range is 380-1180V, the conventional input voltage value of the railway substation incoming line side is 380V, and the preset high voltage is to be boosted, so the lower limit of the preset high voltage is 380V, and the upper limit is set to 1180V based on the comprehensive consideration of adapting to the low-voltage side power-on of the subway DC power supply system and meeting the aforementioned signal collection.

[0059] In a more specific embodiment, a railway substation low-voltage side power-on detection device mainly includes two parts, namely an operation control cabinet and a power supply box, and the aforementioned boost module, collection module and display module can be integrated in the operation control cabinet and power supply box. The modules can be connected to each other or externally connected through a series of interfaces provided on the surface of the cabinet-shaped power-on detection device. The specific connection mode of the circuit panel during operation can be referred to Figure 3 . The power socket of the operation control cabinet is used to connect the three-phase alternating current power supply; the control cabinet output interface of the operation control cabinet is used to connect the power supply box input interface of the power supply box; and the power supply box output interface of the power supply box is used to connect the load of the railway substation incoming line side. The low-voltage side power-on detection device can boost the voltage of the three-phase alternating current power supply and output through the power supply box output interface. The output voltage range is 0-1180V, which can be adjusted, and more preferably, the voltage adjustment range is 380-1180V.

[0060] The basic detection principle of the power-on detection device is: using electromagnetic induction principle to customize a test device with automatic voltage regulation function, using a single-chip microcomputer control board to receive, send and store current and voltage signals to the register to realize sampling function, judging whether the output value reaches the set value, and then using 485 communication to start or close the frequency converter to realize three-phase motor voltage regulator boost or shutdown. Among them, in the protection design, the single-chip microcomputer control board compares the real-time collected signal value with the set value, and when it is higher than the set value, the alarm information is displayed on the display screen and the output is turned off; in the basic parameter determination, the transformer capacity, transformer wiring mode, transformer high-low voltage side mutual inductor configuration and transformation ratio, feeder side bus type and other factors of conventional speed railway, passenger dedicated line and high-speed railway are comprehensively compared and selected; in the function configuration, it needs to have protection devices, display screens, sensors, operation software and other auxiliary facilities, especially whether the test device can meet the demand of normal operation under the low-voltage side short-circuit working condition of the transformer.

[0061] According to the current application scene requirements, considering the factors such as the transformer capacity of the general speed railway, passenger dedicated line and high speed railway, the transformer wiring mode, the configuration and transformation ratio of the transformer high and low voltage side mutual inductor, and the feeder side bus type, etc., the 220KV / 63MVA transformer of a substation of a high speed railway is finally determined as an example to calculate the capacity of the test device. If the output voltage of the detection device is increased to 1180V and connected to the front end of the high voltage side voltage mutual inductor of the substation, according to the nameplate information of the single-phase traction transformer, the short circuit impedance voltage is 10.54-10.58%, the rated current is 286.36A, the short circuit impedance is taken as the maximum value of 10.58%, the impedance voltage is 220kV*0.1058=23.276kV, the high voltage side is pressurized to 1180V, which is 5.07% of the impedance voltage (1.18 / 23.276), the high voltage side current value is calculated according to the voltage proportion value, which is 14.518A (286.36*0.0507), so the detection device capacity is: 1180V*14.518=17.13kVA, the load rate is calculated as 0.85, so the actual required test device capacity is 17.13 / 0.85=20.15kVA, which can meet the requirements of the 220KV / 63MVA single-phase transformer with a short circuit impedance of 10.58% under the low voltage side short circuit working condition of the transformer.

[0062] The core function of the power-on detection equipment is to meet the condition of short circuit of the low voltage side of the transformer of the railway substation, and the high voltage side construction is pressurized, so that the high voltage side protection device can collect the current, voltage and phase and automatically record the related data to display the hexagon diagram. The main parameter of whether the power-on detection equipment can be successfully energized is whether the capacity of the power-on detection equipment can meet the normal working condition of the low voltage side short circuit of the 63MVA transformer of the railway substation.

[0063] According to the parameter calculation, the test transformer capacity is finally determined as 20kVA, which can meet the requirements of the 220KV / 63MVA, V / V wiring transformer with a short circuit impedance of 10.58%, the low voltage side short circuit working condition of the transformer for 60 minutes and the short circuit side current less than 35A.

[0064] Determination of the technical parameters of the equipment: ①Through the calculation of the power box capacity is 17 kVA; power voltage form is three-phase; input rated current: 25.8A; output rated current: 8.32A; output rated voltage: 0-1180V (continuous adjustable). ②The main technical parameters of the operation control cabinet are determined as follows: rated capacity: 20 kVA; power voltage form is three-phase; waveform distortion is less than 3%; measurement accuracy: 0.5% FS ± 3 words; resolution: 0.1V; output current: AC 0-40A; resolution: 0.01A; input and output phasor diagram display; through data analysis, the current, power and other related data at the specified voltage can be calculated; portable structure, the overall design structure is reasonable, reliable and durable; the equipment has modular structure, which is convenient for maintenance. ③The input and output have main overcurrent, short circuit, overload and overvoltage protection functions, and the alarm lamp flashes after DC feeding; the emergency disconnecting button is set, which will stop the work of the power box and make it emergency disconnect the power supply, and the electric siren will alarm; when the main circuit voltage is lower than the warning value or the current exceeds the warning value, the power box will automatically disconnect and the fault indicator will light.

[0065] The protection circuit is designed to include a power frequency transformer, a rectifier bridge, an LDO positive output IC, an LDO negative output IC, a current transformer, an operational amplifier, a delay IC, etc. The LDO supplies power to the operational amplifier and the delay circuit, the current is converted into an alternating voltage signal through the current transformer, and then the signal is amplified by the operational amplifier and sent to the delay IC. When the current exceeds the set value, the changing signal is sent to the single-chip microcomputer control board.

[0066] Using the automatic voltage regulation function, input the set voltage value to the single-chip microcomputer control board on the display screen. The single-chip microcomputer control board receives the voltage value and stores it in the register, and reads the output table head voltage value.

[0067] If the current voltage value is less than the set voltage value, start the frequency converter using 485 communication, close the input and output contactor, and at this time the three-phase motor voltage regulator boosts the voltage.

[0068] When the table head voltage value is equal to the set voltage value, the frequency converter is turned off, and at this time the output is stable.

[0069] The single-chip microcomputer control board compares the real-time collected signal value with the set value, and if it is higher than the set value, it displays alarm information on the display screen and turns off the output.

[0070] The single-chip microcomputer control board includes a main control IC-STM32F103RCT6, an AC220V to DC5V converter, a 5V to 3.3V LDO, a TTL to 485 circuit, a display screen communication control circuit, a TTL to 232 circuit, etc.

[0071] The following is a specific introduction to the panel of the railway substation low-voltage side power-on detection equipment. A panel of the operation control cabinet is referred to Figure 3Wherein, the load feedback input interface can include two meter input interfaces, each of which includes three-phase voltage and current input interfaces.

[0072] Meter input interface 1 (one of the input interfaces of the aforementioned acquisition module): signal input meter input interface 1 of the voltage and current transformers of the load feedback loop (400V / 5A).

[0073] Meter input interface 2 (the other input interface of the aforementioned acquisition module): signal input meter input interface 2 of the voltage and current transformers of the load feedback loop (400V / 5A).

[0074] Power socket: three-phase five-wire power input, i.e. the three-phase power input of the incoming line side of the railway substation.

[0075] Grounding Figure 3 (not shown): power supply grounding.

[0076] Control cabinet signal input interface: connected to the power supply box signal output interface.

[0077] The wiring mode of meter input interface 1 is shown in Figure 4 The same applies to meter input interface 2. After connecting input meters 1 and 2, the input voltage range, input current range, voltage transformation ratio, and current transformation ratio of the input meter need to be adjusted on the meter.

[0078] The reference Figure 3 .

[0079] Power supply box input interface: connected to the control cabinet output interface.

[0080] Power supply box output interface (including three-phase interface, where yellow: A phase, green: B phase, red: C phase, and black: zero line. The power supply box output interface is connected to the output interface of the aforementioned voltage boosting module): connected to the external load.

[0081] Grounding Figure 3 (not shown): power supply grounding.

[0082] Power supply box signal output interface: connected to the control cabinet signal input interface.

[0083] The railway low-voltage side power-on detection device needs to be correctly wired according to the electrical design drawings before it is put into use. It is important to first connect the signal input and output lines and then connect the power input and output lines. After the device is wired, it needs to be configured with minimum / maximum input voltage, minimum / maximum output current, output maximum power, and output step voltage, etc. parameters according to actual needs. After the parameter configuration is completed, it can be used for testing and application.

[0084] The parameter test interface is entered into the device main interface, the test interface displays input / output three-phase line voltage, input / output three-phase phase current, input / output frequency and test time, the output voltage size can be adjusted through the "+" or "-" options of the step voltage, and the test can be started after the above parameters are configured. The display interface during the parameter test process displays the input and output in real time.

[0085] After the test is completed, the output voltage will slowly decrease, and a "stop output" dialog box will pop up to indicate that the discharge is complete. If the step-up transformer is not reset, it needs to be reset. Before the reset is completed, the alarm signal light on the detection device will continue to light up on the low voltage side of the railway, among which the green signal indicates the output state display, the red signal indicates the voltage output display, the yellow signal indicates the input / output overcurrent, input / output overvoltage and other abnormal conditions, and the buzzer indicates the emergency stop button.

[0086] After the parameter test is completed, the protection function test also needs to be performed to verify the availability of the functions of the device, such as output active power, output reactive power, output apparent power, power factor, output vector, overvoltage / overcurrent protection, overload or short circuit alarm, and meter head fault alarm. Among them, in terms of device protection, when the input voltage (current) of any phase is greater than the set voltage (current) value, the "input voltage (current) is too high!" warning will pop up and the output will be cut off; when the output power is greater than the set maximum power, the "output power is too large!" warning will pop up and the output will be cut off; when any phase output is short-circuited, the "output short-circuit!" warning will pop up and the output will be cut off; when the input (output) meter head is abnormal, the "input (output) meter head fault!" warning will pop up and the output will be cut off; when the emergency stop button on the panel is pressed, the "emergency stop pressed!" warning will pop up and the output will be cut off. After all the input and output protection functions are verified to be reliable, the device can be formally used.

[0087] The above description is only an exemplary embodiment of the present disclosure, and cannot limit the scope of the present disclosure. That is, any equivalent changes and modifications made in accordance with the teachings of the present disclosure are still within the scope of the present disclosure. Other embodiments of the present disclosure will be readily apparent to those skilled in the art upon considering the specification and practicing the disclosure herein. The present application is intended to cover any variations, uses or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or conventional techniques in the art not described in the present disclosure. The specification and examples are only considered to be exemplary, and the scope and spirit of the present disclosure are defined by the claims.

[0088] The technical features of the above embodiments can be combined in any way, and to make the description concise, not all possible combinations of the technical features in the above embodiments are described in detail, however, as long as the combinations of the technical features do not exist contradictory, they should be considered as the scope of the present disclosure.

[0089] It is to be understood that the above description is intended to be illustrative and not restrictive. Many other embodiments will be apparent to those of skill in the art upon reading the above description. The scope of the application should therefore, be determined not with reference to the above description, but should instead be determined with reference to the appended claims, along with their full scope of equivalents. The disclosure of all articles and references referred to herein are incorporated by reference in their entirety.

Claims

1. A method of energization detection on the low voltage side of a railway substation, characterized in that, include: The initial voltage of the three-phase AC power supply on the incoming side of the railway substation is boosted to a preset high voltage, the value of which is adjustable. The preset high voltage is output to the front end of the load on the incoming line side of the railway substation to energize the load; A primary voltage and current loop is formed between the incoming voltage transformer, the incoming current transformer, the transformer, the transformer low-voltage current transformer, the transformer low-voltage voltage transformer and ground. After the loop is formed, the current and voltage sampling status is checked on each protection device in the control signal panel, and it is determined whether the differential current and braking current values ​​on the transformer main protection device meet the requirements of the protection device. Collect the current, voltage, and phase signals of the voltage transformers and / or current transformers on the substation load after the voltage is stepped up; The system displays the collected signal values, compares the collected current and voltage signal values ​​with preset signal values ​​to obtain the detection results, and displays alarm information and shuts off the output when the values ​​exceed the preset signal values. The preset high voltage ensures that when the low-voltage side of the railway substation transformer is short-circuited, current, voltage, and phase signals can be collected on the high-voltage side when the preset high voltage is applied.

2. The power-on detection method of claim 1, wherein, The preset high voltage range is 380~1180V.

3. The power-on detection method of claim 2, wherein, The preset high voltage is 1180 V.

4. The power-on detection method of claim 1, wherein, When acquiring the current, voltage, and phase signals of the voltage transformers and / or current transformers on the substation load after voltage boosting, the acquired current, voltage, and phase signal values ​​and the corresponding hexagonal diagrams are displayed simultaneously.

5. The power-on detection method of claim 1, wherein, The process of boosting the initial voltage to a preset high voltage includes: Set a preset high voltage to the microcontroller control board; After receiving the preset high voltage, the microcontroller control board stores it in the register and acquires the output meter voltage value. If the output meter voltage value is determined to be less than the preset high voltage, the inverter is started using 485 communication, and the input / output contactor is closed to make the three-phase electric voltage regulator boost the voltage to the preset high voltage.

6. The power-on detection method of claim 5, wherein, After the initial voltage is boosted to the preset high voltage, the following is also included: If the output meter voltage value is determined to be equal to the preset high voltage, the frequency converter is turned off to ensure a stable output of the preset high voltage.

7. The power-on detection method of claim 1, wherein, The preset signal value is a preset signal value range or a preset signal single-point value; the preset signal value is input through a data display device.

8. A railway substation low voltage side power-on detection device for implementing the power-on detection method according to any one of claims 1 to 7, characterized in that, include: Boost module, data acquisition module, and display module; The boost module is used to boost the initial voltage of the three-phase AC power supply on the incoming side of the railway substation to a preset high voltage, and output the preset high voltage to the front end of the load on the incoming side of the railway substation to energize the load. The acquisition module is used to acquire the current, voltage and phase signals of the voltage transformers and / or current transformers on the substation load after the voltage is stepped up; The display module is used to display the collected signal values, input a preset signal value, and display alarm information when the signal value is higher than the preset signal value.

9. The power-on detection apparatus of claim 8, wherein Also includes: Safety protection module; The safety protection module includes one or more circuit protection mechanisms such as overvoltage protection, overcurrent protection, overload protection, short circuit protection, and meter fault alarm protection. When a fault occurs, it will issue a fault alarm and cut off the output.

10. The power-on detection apparatus of claim 8, wherein The output preset high voltage is adjustable, and the voltage adjustment range is 380-1180 V.

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