Main transformer temperature loop verification method for transformer

Abstract

The invention discloses a main transformer temperature loop verification method for a transformer, and the method comprises the following steps: 1, placing a thermometer temperature-sensing element and a standard thermometer at a temperature measurement point in a transformer oil tank together, and measuring the oil temperature in the oil tank; 2, placing a temperature sensing bulb of a winding thermometer in a constant-temperature oil tank, recording an indication value at the moment after the temperature sensing bulb is kept constant, simulating the operation state of the transformer, applying current to a heating wire, recording the indication value at the moment after a pointer of the thermometer is stable, and calculating a temperature difference value according to temperature data recorded twice; 3, comparing the temperature data measured by the thermometer temperature sensing element with the temperature data measured by the standard thermometer, and recording error data; the oil temperature of the transformer is measured, compared and analyzed through the thermometer temperature sensing element and the standard thermometer at the same time, the winding temperature is measured through a hot-spot temperature rise method, the transformer winding temperature is accurately measured, and the verification effect of a main transformer temperature loop is improved.

Description

Technical Field

[0001] The invention relates to the technical field of main transformer temperature circuit verification, and in particular to a main transformer temperature circuit verification method for a transformer. Background Art

[0002] Transformer refers to a device that uses the principle of electromagnetic induction to change the AC voltage. Transformers can be divided into power transformers and special transformers according to their uses. Power transformers are mainly used in power transmission and distribution lines to change the AC voltage to meet the needs of different users. Special transformers are used in special fields such as smelting, electrical processing, electric traction, communications, and automatic control. Its main components are primary coils, secondary coils, and iron cores. Transformers are basic equipment for power transmission and distribution, and are widely used in industries, agriculture, transportation, urban communities, and other fields. The main transformer temperature circuit calibration is a key step to ensure that the main transformer temperature indication is accurate and the protection system works properly.

[0003] The Chinese patent publication number is CN21917877U, and the authorization announcement date is June 13, 2023. A transformer temperature circuit fault detection device includes: a resistance thermometer, a current thermometer, a first voltmeter, a second voltmeter, a main transformer measurement and control device, a thermal resistor, a sensing unit, a display screen, a resistor, and a current signal generator; the output end of the resistance thermometer is connected to the input end of the thermal resistor, the output end of the current thermometer is connected to the input end of the sensing unit, the output end of the thermal resistor and the output end of the sensing unit are both connected to the display screen, and the output end of the resistor and the output end of the current signal generator are both connected to the input end of the main transformer measurement and control device; the first voltmeter and the sensing unit are connected in parallel, and the second voltmeter and the thermal resistor are connected in parallel; the first voltmeter and the second voltmeter are both connected to the display screen. The utility model has the advantages of simple structure, easy use, complete functions and low cost.

[0004] When checking the temperature circuit of the existing transformer main transformer, a thermometer is generally used to measure the temperature. It is necessary to use a multimeter to test whether each temperature action contact is connected one by one at different temperature values. During the temperature rise period, when measuring different points, it is easy to fail to measure in time when the temperature reaches the set value, which increases the temperature measurement error, affects the accuracy and efficiency of the main transformer temperature circuit verification, and cannot meet the use requirements. Summary of the invention

[0005] The object of the present invention is to provide a method for calibrating the main transformer temperature circuit of a transformer, so as to solve the problem proposed in the above background technology that a thermometer is generally used to measure the temperature when calibrating the main transformer temperature circuit of the existing transformer, and it is necessary to use a multimeter to test whether each temperature action contact is connected one by one at different temperature values. During the temperature rise period, when measuring different points, it is easy to fail to measure in time when the temperature reaches the set value, which increases the temperature measurement error, affects the accuracy and efficiency of the main transformer temperature circuit calibration, and cannot meet the use requirements.

[0006] To achieve the above object, the present invention provides the following technical solution: a method for checking the temperature circuit of a main transformer of a transformer, comprising an acquisition module, a check module, an alarm module and a terminal, wherein the acquisition module is divided into oil temperature measurement and winding temperature measurement, and the check module includes data recording, data comparison, data storage and data display, comprising the following steps:

[0007] Step 1: Place the thermometer sensing element and the standard thermometer at the temperature measuring point in the transformer oil tank to measure the oil temperature in the oil tank;

[0008] Step 2: Place the temperature sensing package of the winding thermometer in a constant temperature oil tank, keep it constant and record the indicated value at this time, simulate the operation state of the transformer, apply current to the heating wire, record the indicated value at this time after the pointer of the thermometer stabilizes, and calculate the temperature difference value based on the temperature data recorded twice;

[0009] Step 3: Compare the temperature data measured by the thermometer temperature sensing element with the temperature data measured by the standard thermometer, and record the error data;

[0010] Step 4: Compare the temperature difference value of the winding temperature measurement with the preset value to ensure that the error is within the allowable range, and store and back up the qualified temperature data;

[0011] Step 5: The calibration results are directly displayed on the LCD screen. When the calibration results are abnormal, the alarm module is automatically triggered to issue an alarm.

[0012] Step 6: Upload the calibration result data to the terminal via wireless communication. The staff can retrieve the calibration data remotely and perform simple operations.

[0013] Preferably, a regular time is set for the main transformer temperature circuit check, and the main transformer temperature circuit check is performed regularly.

[0014] Preferably, in step 1, when measuring the oil temperature, the oil temperature is controlled to be close to the atmospheric temperature, and the upper layer oil temperature shall not exceed 95° C. when the ambient temperature is 40° C.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. The invention measures the temperature of the transformer winding by the hot spot temperature rise method, and uses the top oil temperature of the power transformer plus the temperature difference between the hottest point of the transformer winding and the oil to simulate and measure the hot spot temperature rise of the transformer winding. According to the relationship between the transformer load loss and the load current, the hot spot temperature is obtained by simulating the temperature rise of the winding relative to the top oil temperature. The hot spot temperature and hot spot temperature rise of the winding can be accurately measured, and the calibration accuracy of the main transformer temperature circuit of the transformer is improved to ensure its accuracy and reliability.

[0017] 2. The invention uploads the calibration result data to the terminal through wireless communication, and the staff can retrieve the calibration data remotely and perform simple operations. When the calibration result is abnormal, the alarm module is automatically triggered to issue an alarm, thereby improving the calibration effect of the main transformer temperature circuit;

[0018] 3. The invention can reduce errors by setting a regular calibration time and regularly adjusting or calibrating the thermometer. Regular calibration of the main transformer temperature circuit can ensure the accuracy and reliability of temperature indication. The oil temperature is measured close to the atmospheric temperature, and the error is controlled within ±5°C, which can reduce measurement errors and improve the calibration effect of the main transformer temperature circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural block diagram of the main transformer temperature loop verification of the present invention; DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0021] See also Figure 1 The present invention provides an embodiment: a method for checking the main transformer temperature circuit of a transformer, comprising an acquisition module, a check module, a warning module and a terminal, wherein the acquisition module is divided into oil temperature measurement and winding temperature measurement, and the check module includes data recording, data comparison, data storage and data display, comprising the following steps:

[0022] Step 1: Place the thermometer sensing element and the standard thermometer at the temperature measuring point in the transformer oil tank to measure the oil temperature in the oil tank;

[0023] Step 2: Place the temperature sensing package of the winding thermometer in a constant temperature oil tank, keep it constant and record the indicated value at this time, simulate the operation state of the transformer, apply current to the heating wire, record the indicated value at this time after the pointer of the thermometer stabilizes, and calculate the temperature difference value based on the temperature data recorded twice;

[0024] Step 3: Compare the temperature data measured by the thermometer temperature sensing element with the temperature data measured by the standard thermometer, and record the error data;

[0025] Step 4: Compare the temperature difference value of the winding temperature measurement with the preset value to ensure that the error is within the allowable range, and store and back up the qualified temperature data;

[0026] Step 5: The calibration results are directly displayed on the LCD screen. When the calibration results are abnormal, the alarm module is automatically triggered to issue an alarm.

[0027] Step 6: Upload the calibration result data to the terminal via wireless communication. The staff can retrieve the calibration data remotely and perform simple operations.

[0028] See also Figure 1 , set a regular time for the main transformer temperature circuit verification, regularly adjust or calibrate the thermometer to reduce errors, and regularly verify the main transformer temperature circuit to ensure the accuracy and reliability of temperature indication.

[0029] See also Figure 1 Step 1: When measuring the oil temperature, control the oil temperature to be close to the atmospheric temperature. The upper oil temperature shall not exceed 95°C when the ambient temperature is 40°C. The oil temperature is measured close to the atmospheric temperature, and the error is controlled within ±5°C. This can reduce the measurement error and improve the verification effect of the main transformer temperature loop.

[0030] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

[0031] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for checking the temperature loop of a transformer main transformer, comprising an acquisition module, a check module, a warning module and a terminal, wherein the acquisition module is divided into oil temperature measurement and winding temperature measurement, and the check module includes data recording, data comparison, data storage and data display, characterized in that: The following steps are involved: Step 1: Place the thermometer sensing element and the standard thermometer at the temperature measuring point in the transformer oil tank to measure the oil temperature in the oil tank; Step 2: Place the temperature sensing package of the winding thermometer in a constant temperature oil tank, keep it constant and record the indicated value at this time, simulate the transformer operation state, apply current to the heating wire, record the indicated value at this time after the thermometer pointer stabilizes, and calculate the temperature difference value based on the temperature data recorded twice; Step 3: Compare the temperature data measured by the thermometer temperature sensing element with the temperature data measured by the standard thermometer, and record the error data; Step 4: Compare the temperature difference value of the winding temperature measurement with the preset value to ensure that the error is within the allowable range, and store and back up the qualified temperature data; Step 5: The calibration results are directly displayed on the LCD screen. When the calibration results are abnormal, the alarm module is automatically triggered to issue an alarm. Step 6: Upload the calibration result data to the terminal via wireless communication. The staff can retrieve the calibration data remotely and perform simple operations.

2. A method for checking the main transformer temperature circuit of a transformer according to claim 1, characterized in that: The main transformer temperature circuit check is performed at a regular time.

3. A method for checking the main transformer temperature circuit of a transformer according to claim 1, characterized in that: In the step 1, when measuring the oil temperature, the oil temperature is controlled to be close to the atmospheric temperature, and the upper layer oil temperature shall not exceed 95° C. when the ambient temperature is 40° C.

Images