Automatic detection device for choke transformer

Abstract

The utility model relates to the technical field of electrical variable measurement, in particular to an automatic detection device for a choke transformer, which comprises an input power supply, a detection circuit and a microcomputer for adjusting the detection circuit. The detection circuit comprises a signal source which is connected to a microcomputer through a serial port and is used for generating a sine wave signal and transmitting the sine wave signal to a switch unit through a data line; the switch unit is respectively connected to the adjusting unit and the detection unit and is used for changing a circuit connection mode according to an instruction of the microcomputer so as to realize different detection items; the adjusting unit is used for adjusting relevant parameters in the detection circuit; according to the utility model, the circuit connection mode can be rapidly and accurately changed, the automatic detection process switching can be realized, and compared with the traditional manual switch switching, the switching speed is improved, and the complexity and error of manual operation are reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of electric variable measurement, in particular to an automatic detection device for a choke transformer. Background Art

[0002] In railway signaling, a track circuit is a system consisting of transmitting equipment, rail lines, and receiving equipment. Its function is to detect whether a section of track line is occupied by a train. The normal operation of the track circuit is crucial. Once a failure occurs, it can cause train delays at best, or even cause subsequent trains to enter the occupied track line, resulting in extremely serious consequences. As a key component of track circuit equipment, the choke transformer needs to pass the traction current during operation and ensure that the traction current does not affect the equipment behind it. Therefore, the electrical indicators of the track circuit equipment must be tested before installation and during operation to ensure that they meet the requirements. The testing of the choke transformer is a key link in this process.

[0003] However, the current choke transformer detection mainly consists of a signal source, a voltage regulator, a measuring instrument, wires, resistors and other accessories. During the test, the tester needs to manually adjust the voltage, then use the instrument to measure the relevant indicators and record the results in a dedicated table. Some indicators also need to be calculated. This method is relatively primitive and the test workload is huge. Alternatively, the equipment is integrated into a box. Due to the large size of the signal source and voltage regulator, the box is generally designed with a pull rod for easy dragging. During the test, the tester also needs to manually adjust the voltage regulator, resistors, etc. Although the integrated microcomputer can save and manage the test records, the degree of automation of this method is still limited. During the test process, it is still necessary to manually adjust the signal and confirm the correctness of the adjustment result. In addition, the equipment is large and difficult to carry. At this stage, there is a need for an automatic detection device for choke transformers. Utility Model Content

[0004] In order to solve the problems of low automation and heavy testing workload in a choke transformer detection method, the utility model provides an automatic detection device for a choke transformer.

[0005] In a first aspect, the present invention provides an automatic detection device for a choke transformer, which adopts the following technical solution:

[0006] An automatic detection device for a choke transformer, comprising:

[0007] an input power supply, a detection circuit, and a microcomputer for regulating the detection circuit;

[0008] The detection circuit includes: a signal source connected to a microcomputer via a serial port, for generating a sine wave signal, and transmitting the sine wave signal to a switch unit via a data line;

[0009] The switch unit is connected to the adjustment unit and the detection unit respectively, and is used to change the circuit connection mode according to the instruction of the microcomputer to realize different detection items;

[0010] An adjustment unit, used for adjusting relevant parameters in the detection circuit;

[0011] The detection unit is used to detect the choke transformer and obtain relevant detection data.

[0012] Furthermore, the input power supply includes a transformer with two independent secondary winding structures, which converts the input alternating current into dual-path direct current with different voltages. One output end of the transformer is connected to the microcomputer and various components in the detection circuit, and the other output end of the transformer is connected to a choke transformer.

[0013] Furthermore, the signal source includes a signal synthesizer and a power amplifier, the signal synthesizer is connected to the power amplifier, and the sinusoidal wave signal generated by the signal source is amplified by the power amplifier and transmitted to the switch unit.

[0014] Furthermore, the switch unit includes multiple groups of 485 / 8-way intelligent switches, and the 485 / 8-way intelligent switches are connected to the microcomputer via a 485 serial port.

[0015] Furthermore, the adjustment unit includes a driving component and an adjustable resistor, the driving component is connected to an adjustment knob of the adjustable resistor via a coupling, and a control end of the driving component is connected to a microcomputer.

[0016] Furthermore, the driving component includes a stepper motor and a stepper motor controller. The stepper motor controller is connected to a microcomputer via a 485 serial port and is used to receive control instructions from the microcomputer. The stepper motor drives the coupling to rotate the knob of the adjustable resistor according to the instructions of the 485 stepper motor controller.

[0017] Furthermore, the detection unit includes a voltage measuring component and an ammeter, and the ammeter is connected in series between the signal source and the adjustable resistor to measure the current flowing into the circuit.

[0018] Furthermore, the voltage measuring component includes an AC voltmeter V1, an AC voltmeter V2, an AC voltmeter V3 and an AC voltmeter V4, the AC voltmeter V1 is connected between the output end of the signal source and the adjustable resistor, the AC voltmeter V2 is connected in parallel with the adjustable resistor, the AC voltmeter V3 is connected in parallel between the adjustable resistor and the choke transformer, and the AC voltmeter V4 is connected to the secondary coil of the choke transformer.

[0019] Furthermore, the voltage measuring component further includes a DC voltmeter V5, and the DC voltmeter V5 is connected to the secondary coil of the choke transformer via a wire.

[0020] Furthermore, the signal source adopts a signal source with a minimum frequency resolution of 1uHz and a minimum amplitude resolution of 1mV.

[0021] In summary, the present invention has the following beneficial technical effects:

[0022] 1. The switch unit of this utility model adopts multiple groups of 485 / 8-way intelligent switches, which are connected to the microcomputer through the 485 serial port. The microcomputer can send instructions according to different detection items. The intelligent switch can quickly and accurately change the circuit connection mode and realize automatic detection process switching. Compared with traditional manual switch switching, it not only improves the switching speed, but also reduces the complexity and error of manual operation.

[0023] 2. The utility model integrates the power interface, detection circuit, microcomputer and other hardware into one to form a complete automatic detection system. This integrated design reduces the connection complexity between devices, avoids operational errors caused by improper connection of multiple independent devices, improves the stability and reliability of the system, and also reduces the workload of manual setting and debugging.

[0024] 3. The adjustment unit of the present invention adopts a stepper motor and a stepper motor controller in conjunction with an adjustable resistor. Through microcomputer control, the stepper motor can accurately drive the coupling to rotate the knob of the adjustable resistor, thereby achieving precise adjustment of relevant parameters in the detection circuit. This hardware design avoids the tedious process of manual repeated adjustment of the resistor, greatly reduces the testing workload, and improves the accuracy and efficiency of parameter adjustment. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of a detection circuit in an automatic detection device for a choke transformer according to an embodiment of the present utility model.

[0026] Figure 2 This is a circuit diagram of an impedance measurement detection item in a detection circuit of an embodiment of the utility model.

[0027] Figure 3 This is a circuit diagram of a turns ratio measurement test item in a detection circuit of an embodiment of the utility model.

[0028] Figure 4 This is a circuit diagram of the same-name terminal measurement detection item in the detection circuit of an embodiment of the utility model.

[0029] Figure 5It is a schematic diagram of the detection process in an automatic detection device for a choke transformer according to an embodiment of the utility model. DETAILED DESCRIPTION

[0030] The present invention will be described in further detail below with reference to the accompanying drawings.

[0031] Example 1

[0032] Reference Figure 1 , an automatic detection device for a choke transformer of this embodiment includes:

[0033] A power supply interface, a detection circuit, and a microcomputer for adjusting the detection circuit;

[0034] The detection circuit includes: a signal source connected to a microcomputer via a serial port, for generating a sine wave signal, and transmitting the sine wave signal to a switch unit via a data line;

[0035] The switch unit is connected to the adjustment unit and the detection unit respectively, and is used to change the circuit connection mode according to the instruction of the microcomputer to realize different detection items;

[0036] An adjustment unit, used for adjusting relevant parameters in the detection circuit;

[0037] The detection unit is used to detect the choke transformer and obtain relevant detection data.

[0038] Specifically,

[0039] like Figure 1As shown, this embodiment is mainly composed of a power supply, a signal source, an intelligent switch, an adjustable resistor, a stepper motor, a voltmeter, an ammeter and a microcomputer. Among them, the power supply is an AC to DC module, and its input is a standard 220V / 50Hz AC power. It has dual outputs, one of which is DC 12V / 5A, which is specially used for the detection of the same end; the other is DC 5V / 2A, which provides power for the micro industrial computer, the voltage and ammeter and the switch module. The connection between the power supply and other components is achieved through wires, and the DC power output is connected to the corresponding equipment to ensure that the components in the detection circuit can work normally. The signal source is the input of the detection circuit and is composed of a signal synthesizer and a power amplifier. It has high-precision frequency and amplitude resolution. The minimum frequency resolution is 1uHz (0.000001Hz) and the minimum amplitude resolution is 1mV (0.001V). It is connected to the micro industrial computer through the serial port, receives the control instructions issued by the micro industrial computer, and returns the execution results to the micro industrial computer. At the same time, the sine wave signal generated by the signal source is amplified by the power amplifier and output to the corresponding detection circuit for the detection of the choke transformer. The microcomputer controls the signal source to generate a signal of corresponding frequency and amplitude, controls the switch to connect the corresponding node, controls the stepper motor to adjust the adjustable resistor to the appropriate resistance value, and finally reads the measurement results of the relevant voltage and ammeter, and calculates the final detection results according to the following method, and stores the results in the non-volatile memory of the micro industrial computer. The intelligent switch adopts 485 / 8-way switch module, has 8-channel switch input or output functions, and uses RS-485 communication protocol for data transmission, such as Figure 5 As shown, in addition, according to the different nodes connected to the switch, the detection of the detection circuit is mainly divided into the following three aspects, namely impedance measurement detection, turns ratio measurement detection and same-name terminal measurement detection.

[0040] like Figure 2As shown in the figure, when performing impedance measurement, K1, K3, and K5 are connected to the lower nodes, and K2, K4, K6, K7, and K8 are connected to the upper nodes. This creates a circuit environment capable of accurately measuring the impedance of a choke transformer. In this circuit, a 25Hz signal is output from the signal source, passing through ammeter A1 and resistor R / 2 ohm / 10W into the choke transformer BE. This connection sequence allows the signal to pass through each component sequentially. Ammeter A1 measures the current flowing into the circuit, while resistor R / 2 ohm / 10W divides the voltage and adjusts circuit parameters. The signal ultimately enters the choke transformer BE for measurement. The control signal source outputs a 25Hz signal with a default amplitude of 3V. The 25Hz frequency is selected based on the electrical characteristics and testing requirements of the choke transformer. This frequency stimulates the relevant characteristics of the choke transformer for accurate measurement. The amplitude is set to 3V to provide an appropriate excitation signal strength in the circuit, ensuring proper circuit operation without affecting measurement accuracy due to excessively strong or weak signals.

[0041] The stepper motor is controlled to adjust the knob of the adjustable resistor. At the same time, the measured values ​​of voltmeters V2 and V3 are automatically compared. In this circuit, voltmeters V2 and V3 respectively measure the voltage at different positions in the circuit. By adjusting the adjustable resistor, the current and voltage distribution in the circuit can be changed.

[0042] When the voltages measured by the two voltmeters are roughly equal, the circuit has reached a specific equilibrium state. From a circuit principle perspective, the interactions between components like resistors, capacitors, and inductors within the circuit have reached a stable state, resulting in more accurate measurements. This equilibrium is achieved by adjusting the adjustable resistor, as changes in the adjustable resistor's value affect the current and voltage distribution within the circuit. When certain conditions are met, the voltages V2 and V3 become equal, and adjustment of the adjustable resistor ceases. Control the signal source's output amplitude. When voltmeter V3 measures 0.4V, read the values ​​measured by ammeter A1 (I), voltmeter V1 (U1), voltmeter V2 (U2), and voltmeter V3 (U3).

[0043] According to formula (1) , calculate the impedance modulus (Z) of the choke transformer. From circuit theory, we know that impedance is the ratio of voltage to current. In this circuit, is the measured value of voltmeter V3, I is the measured value of ammeter A1. Through this formula, the impedance of the choke transformer under the test conditions can be obtained.

[0044] According to formula (2) ,

[0045] Calculate the impedance phase angle of the choke transformer ( ), where U1, U2, and U3 in the formula are the measured values ​​of voltmeters V1, V2, and V3 respectively. This formula can be used to obtain the phase information of the choke transformer impedance.

[0046] like Figure 3 As shown, the turns ratio measurement test items are:

[0047] When measuring the turns ratio, connect K2, K4, K5, and K7 to the lower node, and K1, K3, K6, and K8 to the upper node. This connection method is designed based on the principle of transformer turns ratio measurement and aims to create a circuit environment that can accurately measure the turns ratio of a choke transformer. In this circuit, a 50Hz signal is output from the signal source and flows directly into the choke transformer BE. The 50Hz signal was selected based on the operating frequency characteristics of the choke transformer, as it better reflects the transformer's turns ratio characteristics.

[0048] The control signal source outputs a 50Hz signal with an amplitude of 3V by default. Similar to the impedance measurement, the 50Hz frequency and 3V amplitude are set based on the requirements of the transformer turns ratio measurement and can provide a suitable excitation signal for the measurement. According to formula (3) ,

[0049] in, is the measured value of V3, is the measured value of V4, calculate the turns ratio of the choke transformer ( ), from the transformer principle, we know that the turns ratio is equal to the ratio of the primary and secondary coil voltages. This formula can be used to obtain the ratio of the number of turns of the primary and secondary coils of the choke transformer.

[0050] like Figure 4 As shown, the measurement and test items of the same-name end are:

[0051] When measuring the same-name terminals, K2, K4, and K8 are connected to the lower node, K1, K3, and K7 are connected to the upper node, and K5 and K6 are pulsating (the upper and lower nodes are connected in turn). This connection method is designed based on the principle of same-name terminal measurement. The purpose is to build a circuit environment that can accurately measure the same-name terminals of the choke transformer.

[0052] In this circuit, a 12V DC voltage flows into the choke transformer BE in a pulsating manner through a 180 ohm / 2W resistor. The 12V DC voltage is set based on the requirements for measuring the same-name terminal. The pulsating mode is achieved by pulsating the connection of K5 and K6, which can produce a specific voltage change in the circuit to facilitate the measurement of the same-name terminal.

[0053] (1) Principle of the first measurement

[0054] Control the upper node of switch K5 and the lower node of switch K6 to be connected, while simultaneously reading U51 of voltmeter V5. In this circuit, V5 measures the voltage associated with the same-named terminal in the circuit. When the upper node of K5 and the lower node of K6 are connected, the current and voltage distribution in the circuit changes, affecting the measured value of V5. By reading U51, we can obtain voltage information in one situation, which can be used to determine the same-named terminal in the subsequent determination.

[0055] (2) Re-measurement principle

[0056] Control the lower node of switch K5 and the upper node of switch K6 to connect, and simultaneously read U52 of voltmeter V5. Similarly, when the lower node of K5 and the upper node of K6 are connected, the current and voltage distribution in the circuit will change, affecting the measured value of V5. By reading U52, we can obtain the voltage information of the other situation, which can be used for subsequent judgment of the same terminal.

[0057] (3) Principle of judging the same-name end

[0058] Repeat the above steps. When U51 is larger during the first measurement, and smaller during the second measurement, U52 is smaller, indicating that the same-name terminals are correctly connected. The principle of same-name terminals indicates that these terminals have the same potential in a transformer. In this specific circuit connection and measurement method, if U51 is larger and U52 is smaller, the same-name terminals in the circuit are correctly connected and meet the transformer's same-name terminal characteristics.

[0059] The above are all preferred embodiments of the present invention, and are not intended to limit the scope of protection of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. A choke transformer automatic detection device, characterized in that: include: an input power supply, a detection circuit, and a microcomputer for regulating the detection circuit; The detection circuit includes: a signal source connected to a microcomputer via a serial port, for generating a sine wave signal, and transmitting the sine wave signal to a switch unit via a data line; The switch unit is connected to the adjustment unit and the detection unit respectively, and is used to change the circuit connection mode according to the instruction of the microcomputer to realize different detection items; An adjustment unit, used for adjusting relevant parameters in the detection circuit; The detection unit is used to detect the choke transformer and obtain relevant detection data.

2. The automatic detection device for a choke transformer according to claim 1, characterized in that: The input power supply includes a transformer with two independent secondary winding structures, which converts the input alternating current into dual direct current with different voltages. One output end of the transformer is connected to the microcomputer and various components in the detection circuit, and the other output end of the transformer is connected to the choke transformer.

3. The automatic detection device for choke transformer according to claim 1, characterized in that: The signal source includes a signal synthesizer and a power amplifier. The signal synthesizer is connected to the power amplifier. The sine wave signal generated by the signal source is amplified by the power amplifier and transmitted to the switch unit.

4. The automatic detection device for choke transformer according to claim 1, characterized in that: The switch unit includes multiple groups of 485 / 8-way intelligent switches, and the 485 / 8-way intelligent switches are connected to the microcomputer via a 485 serial port.

5. The automatic detection device for choke transformer according to claim 1, characterized in that: The regulating unit comprises a driving component and an adjustable resistor, the driving component is connected to an adjusting knob of the adjustable resistor via a coupling, and a control end of the driving component is connected to a microcomputer.

6. The automatic detection device for choke transformer according to claim 5, characterized in that: The driving component includes a stepper motor and a stepper motor controller. The stepper motor controller is connected to a microcomputer via a 485 serial port and is used to receive control instructions from the microcomputer. The stepper motor drives the coupling to rotate the knob of the adjustable resistor according to the instructions of the 485 stepper motor controller.

7. The automatic detection device for choke transformer according to claim 1, characterized in that: The detection unit includes a voltage measuring component and an ammeter. The ammeter is connected in series between the signal source and the adjustable resistor to measure the current flowing into the circuit.

8. The automatic detection device for choke transformer according to claim 7, characterized in that: The voltage measuring component includes an AC voltmeter V1, an AC voltmeter V2, an AC voltmeter V3 and an AC voltmeter V4. The AC voltmeter V1 is connected between the output end of the signal source and the adjustable resistor, the AC voltmeter V2 is connected in parallel with the adjustable resistor, the AC voltmeter V3 is connected in parallel between the adjustable resistor and the choke transformer, and the AC voltmeter V4 is connected to the secondary coil of the choke transformer.

9. The automatic detection device for choke transformer according to claim 8, characterized in that: The voltage measuring component further includes a DC voltmeter V5, which is connected to the secondary coil of the choke transformer via a wire.

10. The automatic detection device for choke transformer according to claim 3, characterized in that: The signal source adopts a signal source with a minimum frequency resolution of 1uHz and a minimum amplitude resolution of 1mV.

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