Secondary side resonance elimination device for locomotive high-voltage voltage transformer

Abstract

The utility model discloses a secondary side resonance elimination device for a locomotive high-voltage voltage transformer, and relates to the technical field of high-voltage transformer protection circuits. According to the utility model, output signals when a secondary side N2 coil (voltage) and a primary side coil N1 (current) of a mutual inductor pass through a neutral section are collected, digital signal processing technologies such as digital measurement, filtering and amplification are carried out on the signals through a circuit, and the signals are simultaneously sent to a microprocessor; when a microprocessor detects a low-frequency oscillation phenomenon (current and voltage), the microprocessor controls the conduction of an MOS tube Q1 through an RL1 port via a photoelectric coupler U4 and optical coupler isolation, thereby inputting a load to a secondary coil N3 of a mutual inductor, enabling ferromagnetic resonance to rapidly disappear under the damping effect, and completing the resonance elimination processing. According to the utility model, resonance on-line monitoring and resonance elimination processing are carried out on a running locomotive, and the device is applied to protective equipment for harmonic elimination of a high-voltage mutual inductor at the top of a railway locomotive, a bullet train and the like.

Description

Technical Field

[0001] The utility model relates to the technical field of high-voltage transformer protection circuits, in particular to a secondary side detuning device for a locomotive high-voltage voltage transformer. Background Art

[0002] As the primary carrier of railway transportation, locomotive safety is crucial. High-voltage voltage transformers, part of locomotive high-voltage electrical equipment, primarily perform overhead line voltage measurement, power metering, and protection functions.

[0003] A high-voltage voltage transformer generally refers to a voltage transformer. The primary purpose of a voltage transformer is to transform voltage to power measuring instruments and relay protection devices, measure line voltage, power, and energy, or protect valuable equipment, motors, and transformers in the event of a line fault. The basic structure of a voltage transformer is very similar to that of a transformer. It also has two windings: a primary winding and a secondary winding, both mounted on or wound around an iron core. When the voltage transformer is operating, the primary winding, N1, is connected in parallel to the line, and the secondary winding, N2, is connected in parallel to the instrument or relay. Therefore, when measuring the voltage on a high-voltage line, although the primary voltage is high, the secondary voltage is low, ensuring the safety of both the operator and the instrument.

[0004] At present, there are a few explosion phenomena in the operation of locomotive high-voltage voltage transformers. After research, it is found that the locomotive is in the excessive phase area, which produces ferromagnetic resonance. The ferromagnetic resonance overvoltage is generated according to the locomotive excessive phase process, causing the roof transformer to be burned out. Summary of the Invention

[0005] The purpose of the utility model is to provide a secondary side detuning device for a locomotive high voltage voltage transformer, so as to solve the problems raised in the above background technology.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] A secondary side detuning device for a locomotive high-voltage voltage transformer includes a power supply, a wireless communication unit, a microprocessor, a status indicator light, a voltage acquisition and conditioning circuit, a current acquisition and conditioning circuit, and a load switching circuit.

[0008] The wireless communication unit is communicatively connected to the microprocessor wireless communication unit, the output ends of the power supply, voltage acquisition and conditioning circuit, and current acquisition and conditioning circuit are respectively connected to the input end of the microprocessor, and the output end of the microprocessor is respectively connected to the status indicator light and the input end of the load switching circuit; the input end of the voltage acquisition and conditioning circuit is connected to the voltage interface of the N2 coil on the secondary side of the transformer, and the input end of the current acquisition and conditioning circuit is connected to the current interface of the N1 coil on the primary side of the transformer; the output end of the load switching circuit is connected to the voltage interface of the N3 coil on the secondary side of the transformer.

[0009] Preferably, a current transformer is provided between the current interface of the primary side coil N1 of the transformer and the voltage transformer, and an interface is reserved on the circuit board;

[0010] A metering transformer is provided between the voltage interface of the secondary coil N2 of the transformer and the voltage transformer;

[0011] The voltage interface of the transformer secondary coil N3 is directly connected to the voltage transformer.

[0012] Preferably, the circuit of the microprocessor includes an MCU chip.

[0013] Preferably, the voltage acquisition and conditioning circuit includes an insertion interface P1, an operational amplifier U2A, an operational amplifier U2B and a U1 port;

[0014] The 2nd interface of the plug interface P1, the resistor R4, the 3rd interface of the operational amplifier U2A, the 1st interface of the operational amplifier U2A, the resistor R3, the 5th interface of the operational amplifier U2B, the 7th interface of the operational amplifier U2B and the U1 port are connected in series in sequence;

[0015] Interface 1 of the plug interface P1 is electrically connected between interface 2 of the plug interface P1 and resistor R4 via resistor R7 and capacitor C1, and the resistor R7 and capacitor C1 are connected in parallel;

[0016] The 2nd interface of the operational amplifier U2A is electrically connected between the 1st interface of the operational amplifier U2A and the resistor R3 through the resistor R1, and an external resistor R2 is connected between the 2nd interface of the operational amplifier U2A and the resistor R1; the resistor R2 and the 4th interface of the operational amplifier U2A are grounded respectively, and the 8th interface of the operational amplifier U2A is externally connected to the VCC5V terminal;

[0017] The 6th interface of the operational amplifier U2B is electrically connected between the 7th interface of the operational amplifier U2B and the U1 port. An external resistor R5 is connected between the 7th interface of the operational amplifier U2B and the U1 port. The resistor R5 is grounded.

[0018] The U1 port is electrically connected to the 23 interface of the MCU chip.

[0019] Preferably, the current acquisition and conditioning circuit includes a plug-in interface P2, an operational amplifier U1A, an operational amplifier U1B and an I1 port;

[0020] The 2nd interface of the plug interface P2, the resistor R14, the 3rd interface of the operational amplifier U1A, the 1st interface of the operational amplifier U1A, the resistor R13, the 5th interface of the operational amplifier U1B, the 7th interface of the operational amplifier U1B and the I1 port are connected in series in sequence;

[0021] Interface 1 of the plug interface P2 is electrically connected between interface 2 of the plug interface P2 and the resistor R14 via the resistor R16 and the capacitor C4, and the resistor R16 and the capacitor C4 are connected in parallel;

[0022] The 2nd port of the operational amplifier U1A is electrically connected between the 1st port of the operational amplifier U1A and the resistor R13 via the resistor R10. An external resistor R12 is connected between the 2nd port of the operational amplifier U1A and the resistor R10. The resistor R12 and the 4th port of the operational amplifier U1A are grounded respectively. The 8th port of the operational amplifier U1A is externally connected to the VCC5V terminal.

[0023] The 6th interface of the operational amplifier U1B is electrically connected between the 7th interface of the operational amplifier U1B and the I1 port through the resistor R9. An external resistor R15 is connected between the 7th interface of the operational amplifier U1B and the U1 port. An external resistor R11 is connected between the 6th interface of the operational amplifier U1B and the resistor R9. The resistors R15 and R11 are grounded respectively.

[0024] The I1 port is electrically connected to the 24 interface of the MCU chip.

[0025] Preferably, the load switching circuit includes an interface P3, a rectifier bridge D2, a resistor R17, a photocoupler U4, a resistor R20, a diode D1, a resistor R21, a MOS tube Q1, and a load module;

[0026] The 2nd interface of the plug interface P3, the 1st interface of the rectifier bridge D2, the 3rd interface of the rectifier bridge D2, the resistor R17, the 4th interface of the photoelectric coupler U4, the 3rd interface of the photoelectric coupler U4, the resistor R20, the diode D1, the resistor R21, the G interface of the MOS tube Q1, the S interface of the MOS tube Q1, the load module, the 2nd interface of the rectifier bridge D2, the 4th interface of the rectifier bridge D2 and the 1st interface of the plug interface P3 are connected in series in sequence;

[0027] The D interface of the MOS tube Q1 is electrically connected between the resistor R17 and the 3 interface of the rectifier bridge D2, the 1 interface of the photoelectric coupler U4 is externally connected to the RL1 terminal through the resistor R18, and the 2 interface of the photoelectric coupler U4 is grounded;

[0028] The connection between the load module and the 2nd interface of the rectifier bridge D2 is grounded. An external resistor R23 is connected between the resistor R21 and the G interface of the MOS tube Q1. The other end of the resistor R23 is electrically connected between the load module and the 2nd interface of the rectifier bridge D2.

[0029] The load module includes a resistor R24 and a resistor R25, and the resistor R24 and the resistor R25 are connected in parallel;

[0030] The RL1 terminal is electrically connected to the 60 interface of the MCU chip.

[0031] Preferably, the power supply circuit includes a power supply chip U5, a voltage regulator chip U8, a plug interface P4, and a plug interface P5;

[0032] The 22 interface of the power chip U5 is externally connected to the VCC12V terminal through the diode D6; the 11 interface of the power chip U5 is externally connected to the VCC-5V terminal, and an external capacitor E5 is connected between the 11 interface of the power chip U5 and the VCC-5V terminal;

[0033] The 14 interface of the power chip U5 is externally connected to the VCC5V terminal, and an external capacitor E4 is connected between the 14 interface of the power chip U5 and the VCC5V terminal;

[0034] The capacitor E5 and the capacitor E4 are both grounded.

[0035] The VCC5V terminal, the 3rd interface of the voltage regulator chip U8, the 2nd interface of the voltage regulator chip U8 and the VCC-MCU terminal are connected in series in sequence. The VCC5V terminal, capacitor E6, capacitor C22 and VCC-MCU terminal are connected in series in sequence. An external capacitor C21 is connected between the VCC5V terminal and the 3rd interface of the voltage regulator chip U8, and the capacitor C21 is electrically connected between the capacitor E6 and the capacitor C22; an external capacitor E7 is connected between the 2nd interface of the voltage regulator chip U8 and the VCC-MCU terminal, and the capacitor E7 is electrically connected between the capacitor E6 and the capacitor C22; the 1st interface of the voltage regulator chip U8 is electrically connected between the capacitor E6 and the capacitor C22;

[0036] The connection between the capacitor E6 and the capacitor C22 is grounded;

[0037] The VCC-MCU terminal is electrically connected to the chip MCU.

[0038] Preferably, the wireless communication unit includes a level converter U7, a digital signal isolation chip U6 and a plug-in interface P6;

[0039] The VCC5V terminal is electrically connected to the 1 interface of the level converter U7, and the VCC-MCU terminal is electrically connected to the 8 interface of the level converter U7; the 6 interface of the level converter U7 is externally connected to the USART1_RX terminal, and the 7 interface of the level converter U7 is externally connected to the USART1_TX terminal;

[0040] The 15 interface of the digital signal isolation chip U6 is externally connected to the RS232_RX end, and the 16 interface of the digital signal isolation chip U6 is externally connected to the RS232_TX end; the RS232_RX end is electrically connected to the 2 interface of the plug interface P6, and the RS232_TX end is electrically connected to the 3 interface of the plug interface P6;

[0041] The USART1_RX end is electrically connected to the 69 interface of the MCU chip, and the USART1_TX end is electrically connected to the 68 interface of the MCU chip.

[0042] Preferably, the circuit of the status indicator light includes a light emitting diode D3, a light emitting diode D4 and a light emitting diode D5;

[0043] The light-emitting diode D3 is electrically connected to the VCC-MCU terminal through the resistor R26, the light-emitting diode D4 is electrically connected to the VCC-MCU terminal through the resistor R27; the light-emitting diode D5 is electrically connected to the VCC-MCU terminal through the resistor R28;

[0044] The side of the light-emitting diode D3 away from the resistor R26 is electrically connected to the RUN_LED terminal, the side of the light-emitting diode D4 away from the resistor R27 is electrically connected to the ALARM_LED terminal, and the side of the light-emitting diode D5 away from the resistor R28 is electrically connected to the TR_LED terminal;

[0045] The RUN_LED end is electrically connected to the 2nd interface of the chip MCU, the ALARM_LED end is electrically connected to the 1st interface of the chip MCU; and the TR_LED end is electrically connected to the 3rd interface of the chip MCU.

[0046] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0047] The utility model collects the output signals of the transformer secondary side N2 coil (voltage) and the primary side coil N1 (current) when they are out of phase, and performs digital signal processing technology such as digital measurement, filtering, and amplification on the signals through the circuit, and sends the signals to the microprocessor at the same time; the microprocessor analyzes and calculates the detected data to obtain the fault type (ferromagnetic resonance); the microprocessor passes through the load switching circuit and switches a small resistance (50Ω) to make the ferromagnetic resonance disappear quickly under the action of damping, thereby completing the detuning process; the voltage acquisition and adjustment circuit and the main circuit of the voltage acquisition and adjustment circuit are connected. The main function is to perform secondary amplification processing on the small signal output by the transformer; in the load switching circuit, when the microprocessor detects the (current and voltage) low-frequency oscillation phenomenon, the microprocessor passes through the RL1 port and the photoelectric coupler U4, and the photoelectric coupler isolation controls the MOS tube Q1 to turn on, thereby inputting a load into the secondary coil N3 of the transformer, allowing the ferromagnetic resonance to quickly disappear under the action of damping, thereby completing the detuning process; the utility model performs online resonance monitoring and detuning processing on a running locomotive, and is used as a protective device for eliminating harmonics of high-voltage transformers on the roofs of railway locomotives, EMUs, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0049] Figure 1 This is a principle block diagram of the utility model;

[0050] Figure 2 This is a circuit diagram of the utility model locomotive high voltage voltage transformer;

[0051] Figure 3 This is a circuit diagram of the utility model locomotive high voltage voltage transformer and interface;

[0052] Figure 4 It is a circuit diagram of the microprocessor of the utility model;

[0053] Figure 5 This is a circuit diagram of the voltage acquisition and adjustment circuit of the utility model;

[0054] Figure 6 This is a circuit diagram of the voltage acquisition and adjustment circuit of the utility model;

[0055] Figure 7 This is a circuit diagram of the load switching circuit of the utility model;

[0056] Figure 8 It is a circuit diagram of the power supply of the utility model;

[0057] Figure 9This is a circuit diagram of the wireless communication unit of the utility model;

[0058] Figure 10 It is a circuit diagram of the status indicator light of the utility model. DETAILED DESCRIPTION

[0059] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0060] refer to Figures 1-10 The utility model provides a technical solution: a secondary side harmonic elimination device for a locomotive high-voltage voltage transformer, comprising a power supply, a wireless communication unit, a microprocessor, a status indicator light, a voltage acquisition and conditioning circuit, a current acquisition and conditioning circuit, and a load switching circuit. The wireless communication unit is communicatively connected to the microprocessor wireless communication unit, and the output ends of the power supply, the voltage acquisition and conditioning circuit, and the current acquisition and conditioning circuit are respectively connected to the input end of the microprocessor, and the output end of the microprocessor is respectively connected to the input end of the status indicator light and the load switching circuit; the input end of the voltage acquisition and conditioning circuit is connected to the voltage interface of the transformer secondary side N2 coil, and the input end of the current acquisition and conditioning circuit is connected to the current interface of the transformer primary side N1 coil; the output end of the load switching circuit is connected to the voltage interface of the transformer secondary side N3 coil; a current transformer is provided between the current interface of the transformer primary side coil N1 and the voltage transformer, and an interface is reserved on the circuit board; a metering transformer is provided between the voltage interface of the transformer secondary side coil N2 and the voltage transformer; the voltage interface of the transformer secondary side coil N3 is directly connected to the voltage transformer.

[0061] The circuit of the microprocessor includes an MCU chip; the voltage acquisition and conditioning circuit includes an interface P1, an operational amplifier U2A, an operational amplifier U2B and a U1 port; the interface 2 of the interface P1, the resistor R4, the interface 3 of the operational amplifier U2A, the interface 1 of the operational amplifier U2A, the resistor R3, the interface 5 of the operational amplifier U2B, the interface 7 of the operational amplifier U2B and the U1 port are connected in series in sequence; the interface 1 of the interface P1 is electrically connected between the interface 2 of the interface P1 and the resistor R4 through the resistor R7 and the capacitor C1, and the resistor R7 and the capacitor C1 are connected in parallel; the operational amplifier U2A Interface 2 is electrically connected between interface 1 of the operational amplifier U2A and resistor R3 through resistor R1, and an external resistor R2 is connected between interface 2 of the operational amplifier U2A and resistor R1; the resistor R2 and interface 4 of the operational amplifier U2A are grounded respectively, and interface 8 of the operational amplifier U2A is externally connected to the VCC5V terminal; interface 6 of the operational amplifier U2B is electrically connected between interface 7 of the operational amplifier U2B and port U1, and an external resistor R5 is connected between interface 7 of the operational amplifier U2B and port U1, and the resistor R5 is grounded; the U1 port is electrically connected to interface 23 of the MCU chip.

[0062] The current acquisition and conditioning circuit includes a plug interface P2, an operational amplifier U1A, an operational amplifier U1B and an I1 port; the 2nd port of the plug interface P2, the resistor R14, the 3rd port of the operational amplifier U1A, the 1st port of the operational amplifier U1A, the resistor R13, the 5th port of the operational amplifier U1B, the 7th port of the operational amplifier U1B and the I1 port are connected in series in sequence; the 1st port of the plug interface P2 is electrically connected between the 2nd port of the plug interface P2 and the resistor R14 through the resistor R16 and the capacitor C4, and the resistor R16 and the capacitor C4 are connected in parallel; the 2nd port of the operational amplifier U1A is electrically connected to the 1st port of the operational amplifier U1A and the resistor R1 through the resistor R10 3, an external resistor R12 is connected between the 2 interface of the operational amplifier U1A and the resistor R10; the resistor R12 and the 4 interface of the operational amplifier U1A are grounded respectively, and the 8 interface of the operational amplifier U1A is externally connected to the VCC5V end; the 6 interface of the operational amplifier U1B is electrically connected between the 7 interface of the operational amplifier U1B and the I1 port through the resistor R9, an external resistor R15 is connected between the 7 interface of the operational amplifier U1B and the U1 port, and an external resistor R11 is connected between the 6 interface of the operational amplifier U1B and the resistor R9, and the resistor R15 and the resistor R11 are grounded respectively; the I1 port is electrically connected to the 24 interface of the MCU chip.

[0063] The load switching circuit includes an interface P3, a rectifier bridge D2, a resistor R17, an optocoupler U4, a resistor R20, a diode D1, a resistor R21, a MOS tube Q1, and a load module; the interface 2 of the interface P3, the interface 1 of the rectifier bridge D2, the interface 3 of the rectifier bridge D2, the resistor R17, the interface 4 of the optocoupler U4, the interface 3 of the optocoupler U4, the resistor R20, the diode D1, the resistor R21, the G interface of the MOS tube Q1, the S interface of the MOS tube Q1, the load module, the interface 2 of the rectifier bridge D2, the interface 4 of the rectifier bridge D2, and the interface 1 of the interface P3 are connected in series in sequence; the MOS tube Q1 The D interface of 1 is electrically connected between the resistor R17 and the 3 interface of the rectifier bridge D2, the 1 interface of the photoelectric coupler U4 is externally connected to the RL1 end through the resistor R18, and the 2 interface of the photoelectric coupler U4 is grounded; the connection between the load module and the 2 interface of the rectifier bridge D2 is grounded, and the resistor R21 and the G interface of the MOS tube Q1 are externally connected to the resistor R23, and the other end of the resistor R23 is electrically connected between the load module and the 2 interface of the rectifier bridge D2; the load module includes a resistor R24 and a resistor R25, and the resistor R24 and the resistor R25 are connected in parallel; the RL1 end is electrically connected to the 60 interface of the MCU chip.

[0064] The power supply circuit includes a power supply chip U5, a voltage regulator chip U8, an interface P4, and an interface P5; the 22 interface of the power supply chip U5 is externally connected to the VCC12V terminal through a diode D6; the 11 interface of the power supply chip U5 is externally connected to the VCC-5V terminal, and an external capacitor E5 is connected between the 11 interface of the power supply chip U5 and the VCC-5V terminal; the 14 interface of the power supply chip U5 is externally connected to the VCC5V terminal, and an external capacitor E4 is connected between the 14 interface of the power supply chip U5 and the VCC5V terminal; the capacitor E5 and the capacitor E4 are grounded respectively; the VCC5V terminal, the 3 interface of the voltage regulator chip U8, the 2 interface of the voltage regulator chip U8 and the VC The C-MCU end is connected in series in sequence, and the VCC5V end, capacitor E6, capacitor C22, and VCC-MCU end are connected in series in sequence. An external capacitor C21 is connected between the VCC5V end and the 3 interface of the voltage regulator chip U8, and the capacitor C21 is electrically connected between the capacitor E6 and the capacitor C22; an external capacitor E7 is connected between the 2 interface of the voltage regulator chip U8 and the VCC-MCU end, and the capacitor E7 is electrically connected between the capacitor E6 and the capacitor C22; the 1 interface of the voltage regulator chip U8 is electrically connected between the capacitor E6 and the capacitor C22; the connection between the capacitor E6 and the capacitor C22 is grounded; the VCC-MCU end is electrically connected to the chip MCU.

[0065] The wireless communication unit includes a level converter U7, a digital signal isolation chip U6 and a plug interface P6; the VCC5V end is electrically connected to the 1 interface of the level converter U7, and the VCC-MCU end is electrically connected to the 8 interface of the level converter U7; the 6 interface of the level converter U7 is externally connected to the USART1_RX end, and the 7 interface of the level converter U7 is externally connected to the USART1_TX end; the 15 interface of the digital signal isolation chip U6 is externally connected to the RS232_RX end, and the 16 interface of the digital signal isolation chip U6 is externally connected to the RS232_TX end; the RS232_RX end is electrically connected to the 2 interface of the plug interface P6, and the RS232_TX end is electrically connected to the 3 interface of the plug interface P6; the USART1_RX end is electrically connected to the 69 interface of the MCU chip, and the USART1_TX end is electrically connected to the 68 interface of the MCU chip.

[0066] The circuit of the status indicator light includes a light-emitting diode D3, a light-emitting diode D4 and a light-emitting diode D5; the light-emitting diode D3 is electrically connected to the VCC-MCU end through a resistor R26, and the light-emitting diode D4 is electrically connected to the VCC-MCU end through a resistor R27; the light-emitting diode D5 is electrically connected to the VCC-MCU end through a resistor R28; the side of the light-emitting diode D3 away from the resistor R26 is electrically connected to the RUN_LED end, the side of the light-emitting diode D4 away from the resistor R27 is electrically connected to the ALARM_LED end, and the side of the light-emitting diode D5 away from the resistor R28 is electrically connected to the TR_LED end; the RUN_LED end is electrically connected to the 2 interface of the chip MCU, the ALARM_LED end is electrically connected to the 1 interface of the chip MCU; the TR_LED end is electrically connected to the 3 interface of the chip MCU.

[0067] Specific working principle:

[0068] There is a current transformer between the transformer primary coil N1 current interface and the device under test (locomotive high-voltage voltage transformer). It is not arranged on the circuit board, and only the interface is left on the circuit board. A small metering transformer is deployed between the transformer secondary coil N2 voltage interface and the device under test (locomotive high-voltage voltage transformer). The transformer secondary coil N3 voltage interface is directly connected to the device under test (locomotive high-voltage voltage transformer).

[0069] Collect the output signals of the transformer secondary side N2 coil (voltage) and primary side coil N1 (current) when they are out of phase, perform digital signal processing such as digital measurement, filtering, and amplification on the signals through the circuit, and send the signals to the microprocessor at the same time;

[0070] The microprocessor analyzes and calculates the detected data to determine the fault type (ferromagnetic resonance);

[0071] The microprocessor passes through the load switching circuit and switches a small resistance (50Ω), allowing the ferromagnetic resonance to disappear quickly under the damping effect, thus completing the detuning process;

[0072] After detuning is completed, the detuning event will be uploaded to the upper platform via the RS232 interface;

[0073] The power supply uses 12V, which is converted to 5V by WRA1205 to power the op amp, and then converted to 3.3V to power the microprocessor;

[0074] The main function of the voltage acquisition and adjustment circuit is to perform secondary amplification on the small signal output by the transformer;

[0075] The wireless communication unit uploads the device status to the upper platform via RS232;

[0076] In the load switching circuit, when the microprocessor detects the low-frequency oscillation phenomenon (current and voltage), the microprocessor passes through the RL1 port and the optocoupler U4, and the optocoupler isolation controls the MOS tube Q1 to turn on, thereby applying a load to the secondary coil N3 of the mutual inductor, allowing the ferromagnetic resonance to quickly disappear under the action of damping, thereby completing the detuning process;

[0077] The secondary of the transformer outputs a power frequency AC signal, which is rectified into a DC signal by D2, a rectifier bridge.

[0078] The secondary harmonic measurement and detuning device of the utility model collects the output signals of the primary side N1 coil and the secondary side N2 coil of the mutual inductor when the phase is excessive, and performs digital signal processing technology such as digital measurement, filtering, and amplification on the signals through the circuit. Then, the detected data is analyzed and calculated to obtain the fault type. When ferromagnetic resonance is found, the system immediately starts the detuning circuit, and the microprocessor quickly controls the coil load of the mutual inductor, so that the ferromagnetic resonance disappears quickly under the action of damping, thereby completing the detuning process.

[0079] The utility model performs online resonance monitoring and harmonic elimination processing on a running locomotive, and is applied to protective equipment for eliminating harmonics of high-voltage mutual inductors on the top of railway locomotives, motor vehicles and the like.

[0080] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art will be able to modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein with equivalents. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A secondary-side detuning device for a high-voltage voltage transformer on a locomotive, comprising a power supply, a wireless communication unit, a microprocessor, a status indicator light, a voltage acquisition and conditioning circuit, a current acquisition and conditioning circuit, and a load switching circuit, characterized in that: The wireless communication unit is communicatively connected to the microprocessor wireless communication unit, the output ends of the power supply, voltage acquisition and conditioning circuit, and current acquisition and conditioning circuit are respectively connected to the input end of the microprocessor, and the output end of the microprocessor is respectively connected to the status indicator light and the input end of the load switching circuit; the input end of the voltage acquisition and conditioning circuit is connected to the voltage interface of the N2 coil on the secondary side of the transformer, and the input end of the current acquisition and conditioning circuit is connected to the current interface of the N1 coil on the primary side of the transformer; the output end of the load switching circuit is connected to the voltage interface of the N3 coil on the secondary side of the transformer.

2. The secondary side detuning device for a locomotive high voltage voltage transformer according to claim 1, characterized in that: A current transformer is provided between the current interface of the primary side coil N1 of the transformer and the voltage transformer, and an interface is reserved on the circuit board; A metering transformer is provided between the voltage interface of the secondary coil N2 of the transformer and the voltage transformer; The voltage interface of the transformer secondary coil N3 is directly connected to the voltage transformer.

3. The secondary side detuning device for a locomotive high voltage voltage transformer according to claim 2, characterized in that: The circuit of the microprocessor includes an MCU chip.

4. The secondary side detuning device for a locomotive high voltage voltage transformer according to claim 3, characterized in that: The voltage acquisition and conditioning circuit includes an insertion interface P1, an operational amplifier U2A, an operational amplifier U2B and a U1 port; The 2nd interface of the plug interface P1, the resistor R4, the 3rd interface of the operational amplifier U2A, the 1st interface of the operational amplifier U2A, the resistor R3, the 5th interface of the operational amplifier U2B, the 7th interface of the operational amplifier U2B and the U1 port are connected in series in sequence; Interface 1 of the plug interface P1 is electrically connected between interface 2 of the plug interface P1 and resistor R4 via resistor R7 and capacitor C1, and the resistor R7 and capacitor C1 are connected in parallel; The 2nd interface of the operational amplifier U2A is electrically connected between the 1st interface of the operational amplifier U2A and the resistor R3 through the resistor R1, and an external resistor R2 is connected between the 2nd interface of the operational amplifier U2A and the resistor R1; the resistor R2 and the 4th interface of the operational amplifier U2A are grounded respectively, and the 8th interface of the operational amplifier U2A is externally connected to the VCC5V terminal; The 6th interface of the operational amplifier U2B is electrically connected between the 7th interface of the operational amplifier U2B and the U1 port. An external resistor R5 is connected between the 7th interface of the operational amplifier U2B and the U1 port. The resistor R5 is grounded. The U1 port is electrically connected to the 23 interface of the MCU chip.

5. The secondary side detuning device for a locomotive high voltage voltage transformer according to claim 4, characterized in that: The current acquisition and conditioning circuit includes an insert interface P2, an operational amplifier U1A, an operational amplifier U1B and an I1 port; The 2nd interface of the plug interface P2, the resistor R14, the 3rd interface of the operational amplifier U1A, the 1st interface of the operational amplifier U1A, the resistor R13, the 5th interface of the operational amplifier U1B, the 7th interface of the operational amplifier U1B and the I1 port are connected in series in sequence; Interface 1 of the plug interface P2 is electrically connected between interface 2 of the plug interface P2 and the resistor R14 via the resistor R16 and the capacitor C4, and the resistor R16 and the capacitor C4 are connected in parallel; The 2nd port of the operational amplifier U1A is electrically connected between the 1st port of the operational amplifier U1A and the resistor R13 via the resistor R10. An external resistor R12 is connected between the 2nd port of the operational amplifier U1A and the resistor R10. The resistor R12 and the 4th port of the operational amplifier U1A are grounded respectively. The 8th port of the operational amplifier U1A is externally connected to the VCC5V terminal. The 6th interface of the operational amplifier U1B is electrically connected between the 7th interface of the operational amplifier U1B and the I1 port through the resistor R9. An external resistor R15 is connected between the 7th interface of the operational amplifier U1B and the U1 port. An external resistor R11 is connected between the 6th interface of the operational amplifier U1B and the resistor R9. The resistors R15 and R11 are grounded respectively. The I1 port is electrically connected to the 24 interface of the MCU chip.

6. The secondary side detuning device for a locomotive high voltage voltage transformer according to claim 5, characterized in that: The load switching circuit includes an interface P3, a rectifier bridge D2, a resistor R17, a photoelectric coupler U4, a resistor R20, a diode D1, a resistor R21, a MOS tube Q1, and a load module; The 2nd interface of the plug interface P3, the 1st interface of the rectifier bridge D2, the 3rd interface of the rectifier bridge D2, the resistor R17, the 4th interface of the photoelectric coupler U4, the 3rd interface of the photoelectric coupler U4, the resistor R20, the diode D1, the resistor R21, the G interface of the MOS tube Q1, the S interface of the MOS tube Q1, the load module, the 2nd interface of the rectifier bridge D2, the 4th interface of the rectifier bridge D2 and the 1st interface of the plug interface P3 are connected in series in sequence; The D interface of the MOS tube Q1 is electrically connected between the resistor R17 and the 3 interface of the rectifier bridge D2, the 1 interface of the photoelectric coupler U4 is externally connected to the RL1 terminal through the resistor R18, and the 2 interface of the photoelectric coupler U4 is grounded; The connection between the load module and the 2nd interface of the rectifier bridge D2 is grounded. An external resistor R23 is connected between the resistor R21 and the G interface of the MOS tube Q1. The other end of the resistor R23 is electrically connected between the load module and the 2nd interface of the rectifier bridge D2. The load module includes a resistor R24 and a resistor R25, and the resistor R24 and the resistor R25 are connected in parallel; The RL1 terminal is electrically connected to the 60 interface of the MCU chip.

7. The secondary side detuning device for a locomotive high voltage voltage transformer according to claim 3, characterized in that: The power supply circuit includes a power supply chip U5, a voltage regulator chip U8, a plug interface P4, and a plug interface P5; The 22 interface of the power chip U5 is externally connected to the VCC12V terminal through the diode D6; the 11 interface of the power chip U5 is externally connected to the VCC-5V terminal, and an external capacitor E5 is connected between the 11 interface of the power chip U5 and the VCC-5V terminal; The 14 interface of the power chip U5 is externally connected to the VCC5V terminal, and an external capacitor E4 is connected between the 14 interface of the power chip U5 and the VCC5V terminal; The capacitor E5 and the capacitor E4 are both grounded. The VCC5V terminal, the 3rd interface of the voltage regulator chip U8, the 2nd interface of the voltage regulator chip U8 and the VCC-MCU terminal are connected in series in sequence. The VCC5V terminal, capacitor E6, capacitor C22 and VCC-MCU terminal are connected in series in sequence. An external capacitor C21 is connected between the VCC5V terminal and the 3rd interface of the voltage regulator chip U8, and the capacitor C21 is electrically connected between the capacitor E6 and the capacitor C22; an external capacitor E7 is connected between the 2nd interface of the voltage regulator chip U8 and the VCC-MCU terminal, and the capacitor E7 is electrically connected between the capacitor E6 and the capacitor C22; the 1st interface of the voltage regulator chip U8 is electrically connected between the capacitor E6 and the capacitor C22; The connection between the capacitor E6 and the capacitor C22 is grounded; The VCC-MCU terminal is electrically connected to the chip MCU.

8. The secondary side detuning device for a locomotive high voltage voltage transformer according to claim 7, characterized in that: The wireless communication unit includes a level converter U7, a digital signal isolation chip U6 and a plug-in interface P6; The VCC5V terminal is electrically connected to the 1 interface of the level converter U7, and the VCC-MCU terminal is electrically connected to the 8 interface of the level converter U7; the 6 interface of the level converter U7 is externally connected to the USART1_RX terminal, and the 7 interface of the level converter U7 is externally connected to the USART1_TX terminal; The 15 interface of the digital signal isolation chip U6 is externally connected to the RS232_RX end, and the 16 interface of the digital signal isolation chip U6 is externally connected to the RS232_TX end; the RS232_RX end is electrically connected to the 2 interface of the plug interface P6, and the RS232_TX end is electrically connected to the 3 interface of the plug interface P6; The USART1_RX end is electrically connected to the 69 interface of the MCU chip, and the USART1_TX end is electrically connected to the 68 interface of the MCU chip.

9. The secondary side detuning device for a locomotive high voltage voltage transformer according to claim 7, characterized in that: The circuit of the status indicator light includes a light emitting diode D3, a light emitting diode D4 and a light emitting diode D5; The light-emitting diode D3 is electrically connected to the VCC-MCU terminal through the resistor R26, the light-emitting diode D4 is electrically connected to the VCC-MCU terminal through the resistor R27; the light-emitting diode D5 is electrically connected to the VCC-MCU terminal through the resistor R28; The side of the light-emitting diode D3 away from the resistor R26 is electrically connected to the RUN_LED terminal, the side of the light-emitting diode D4 away from the resistor R27 is electrically connected to the ALARM_LED terminal, and the side of the light-emitting diode D5 away from the resistor R28 is electrically connected to the TR_LED terminal; The RUN_LED end is electrically connected to the 2nd interface of the chip MCU, the ALARM_LED end is electrically connected to the 1st interface of the chip MCU; and the TR_LED end is electrically connected to the 3rd interface of the chip MCU.

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