Error measuring device of winding temperature controller for transformer

Abstract

The utility model provides an error measuring device of a winding temperature controller for a transformer. The winding temperature controller to be measured comprises a temperature sensing unit; the display unit is coupled with the temperature sensing unit and is suitable for displaying the measured temperature measured by the temperature sensing unit; the current output end is suitable for outputting a current signal related to the measured temperature; the temperature switch is configured to switch the switch state in response to the situation that the measured temperature exceeds the set temperature; the error measuring device comprises a mounting rack; the constant-temperature assembly is installed on the installation frame and suitable for simulating the working environment of a winding of a transformer, and the temperature sensing unit is inserted into the constant-temperature assembly. The standard thermometer is inserted into the constant-temperature assembly and is suitable for acquiring the temperature of the constant-temperature assembly so as to judge whether the winding temperature controller is qualified or not based on the difference value between the temperature of the constant-temperature assembly and the measured temperature; the measuring assembly is installed on the installation frame and is suitable for displaying the output value of the current signal, displaying the far-end temperature according to the output value and recording the measured temperature at the switching moment.

Description

Technical Field

[0001] At least one embodiment of the utility model relates to the technical field of error measurement, and in particular to an error measurement device for a transformer winding temperature controller. Background Art

[0002] The transformer winding thermostat is a device used to monitor and control the winding temperature during the operation of the transformer. Since the transformer generates heat during operation, if the temperature is too high, it may damage the insulation material and affect the safe operation and service life of the transformer. Therefore, the winding thermostat plays a vital role in ensuring the normal operation of the transformer.

[0003] Usually, the oil level temperature and additional temperature rise of the transformer are measured by the winding thermostat to reflect the real temperature inside the transformer. The oil level temperature can be read through the pressure temperature part of the winding thermostat, but the measurement of the additional temperature rise part is more complicated and is a key issue that needs to be addressed. Considering the safety of transformer operation and the importance of the real internal temperature, the indication error, action contact error and other indicators of the winding thermostat need to be accurate and reliable.

[0004] In the related art, the error measurement of the winding temperature controller usually uses multiple measuring devices to measure the single index of the winding temperature controller respectively, but the error measurement of the current signal output by the winding temperature controller is often ignored. In addition, when it is necessary to measure multiple indexes of the winding temperature controller, more measuring devices need to be used, which increases the complexity of the measurement system and may make the measurement process and maintenance more difficult. Utility Model Content

[0005] In order to solve at least one of the technical problems in the prior art, an embodiment of the utility model provides an error measurement device for a transformer winding temperature controller, which can measure multiple indicators of the transformer winding temperature controller and simplify the complexity of the measurement system.

[0006] The embodiment of the utility model provides an error measurement device for a transformer winding temperature controller, characterized in that the winding temperature controller to be measured includes a temperature sensing unit, a display unit, a current output terminal and a temperature switch. The display unit is coupled to the temperature sensing unit and is suitable for displaying the measured temperature measured by the temperature sensing unit. The current output terminal is suitable for outputting a current signal related to the measured temperature. The temperature switch is configured to switch the switch state in response to the measured temperature exceeding the set temperature. The error measurement device includes a mounting frame, a constant temperature component, a standard thermometer and a measuring component. The constant temperature component is mounted on the mounting frame and is suitable for simulating the working environment of the transformer winding. The temperature sensing unit is inserted into the constant temperature component. The standard thermometer is inserted into the constant temperature component and is suitable for obtaining the temperature of the constant temperature component to determine whether the winding temperature controller is qualified based on the difference between the temperature of the constant temperature component and the measured temperature. The measuring component is mounted on the mounting frame and is suitable for displaying the output value of the current signal and displaying the remote temperature according to the output value, and recording the measured temperature at the switching moment.

[0007] According to an embodiment of the utility model, the mounting frame includes a base, a back plate and a mounting portion. The base, the thermostatic assembly is mounted on the base, the back plate extends upward from a first edge of the base, the mounting portion extends horizontally from an upper portion of the back plate toward a second edge of the base opposite to the first edge, and forms a receiving cavity between the back plate and the mounting portion.

[0008] According to an embodiment of the utility model, the measuring assembly includes a DC ammeter, a display and an electric contact display. The DC ammeter is installed in the accommodating cavity, extends outside the mounting portion, and is suitable for measuring and displaying the output value. The display is installed on the mounting portion, and is suitable for displaying the remote temperature based on the output value. The electric contact display is installed on the base, spaced apart from the thermostatic assembly, and electrically connected to the temperature switch, and is suitable for recording the measured temperature at the switching moment of the temperature switch.

[0009] According to an embodiment of the utility model, the mounting frame further comprises a support member, which is installed between the base and the mounting portion and is suitable for providing support for the mounting portion.

[0010] According to an embodiment of the utility model, the thermostatic component includes a shell, a thermostatic bath and a heating unit. A cavity is formed inside the shell, which is installed on the base, and an opening is opened on the top of the shell. A solution is contained inside the thermostatic bath, and the thermostatic bath is installed in the cavity and is located below the opening. The heating unit is installed in the thermostatic bath and is suitable for heating the solution so that the solution maintains a target temperature. The temperature sensing unit extends from the opening into the thermostatic bath.

[0011] According to an embodiment of the utility model, the thermostatic component further comprises a standard temperature display unit which is mounted on the housing, electrically connected to the standard thermometer and the heating unit, and is suitable for setting the target temperature and displaying the temperature of the thermostatic component.

[0012] According to an embodiment of the utility model, the winding temperature controller further includes a heating wire. The heating wire is wound on the temperature sensing unit and is suitable for generating heat to simulate the additional temperature rise of the transformer. The measuring component further includes an AC constant current source. The AC constant current source is installed in the accommodating cavity and extends outside the mounting portion, and is suitable for providing a working current for the winding temperature controller. Among them, by toggling the current switch in the winding temperature controller, the current switch provides the heating wire with the thermal simulation current under the action of the working current.

[0013] According to an embodiment of the utility model, the measuring component also includes an AC ammeter, which is installed in the accommodating cavity, extends outside the mounting portion, and is spaced apart from the AC constant current source, and is suitable for obtaining a monitoring current of the thermal simulation current.

[0014] According to an embodiment of the utility model, the error measuring device further includes two first terminals and two second terminals. The two first terminals are mounted on the mounting portion, wherein one end of one of the first terminals is electrically connected to the current switch, one end of the other first terminal is electrically connected to the AC ammeter, and the other ends of the two first terminals are connected to the two ends of the heating wire to connect the AC ammeter in series between the current switch and the heating wire. The two second terminals are mounted on the mounting portion and are spaced apart from the two first terminals, one end of the two second terminals is electrically connected to the DC ammeter, and the other end is pluggable and electrically connected to the current output end.

[0015] According to an embodiment of the utility model, there are multiple current output terminals, and the error measuring device further includes two third terminals and a resistor. The two third terminals are mounted on the mounting portion and are spaced apart from the two first terminals. The resistor is connected across the two third terminals and is suitable for converting one of the current signals into a voltage signal.

[0016] According to an embodiment of the utility model, the mounting frame further comprises a plurality of universal wheels, which are mounted on the bottom plate of the base.

[0017] According to the error measuring device of the transformer winding temperature controller of the embodiment of the utility model, by integrating the thermostatic component and the measuring component on the mounting frame, multiple indicators of the transformer winding temperature controller can be measured, the complexity of the system is reduced, the maintenance difficulty of the error measuring device is reduced and the measurement process is simplified. The thermostatic component provides a constant temperature environment to avoid the influence of temperature changes in the external environment. A standard thermometer is set in the thermostatic component, and the temperature of the thermostatic component is detected by the standard thermometer. Then, in the process of measuring the error of the winding temperature controller to be measured, the output value of the current signal at the current output end of the winding temperature controller is measured and displayed by the measuring component. According to the linear relationship between the output value and the temperature value, the output value can be converted into a temperature value, and then the temperature value is compared with the temperature of the thermostatic component, and the remote error between the output value and the temperature of the thermostatic component can be obtained; according to the comparison of the measured temperature displayed by the display unit of the winding temperature controller and the temperature of the thermostatic component detected by the standard thermometer, the difference between the measured temperature and the temperature of the thermostatic component can be obtained, and the difference is used as the indication error. By measuring and recording the measured temperature of the temperature switch when the measured temperature is near the set temperature and the temperature switch is switched, the switching error of the temperature switch can be obtained. According to the standard error range of the winding temperature controller, it can be judged whether the winding temperature controller to be tested is qualified. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and other purposes, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

[0019] Figure 1 A system diagram schematically shows an error measurement device for a transformer winding temperature controller according to an embodiment of the utility model;

[0020] Figure 2 A first perspective stereogram schematically shows an error measuring device for a transformer winding temperature controller according to an embodiment of the utility model; and

[0021] Figure 3 A second perspective stereogram schematically shows an error measuring device for a transformer winding temperature controller according to an embodiment of the utility model; and

[0022] Figure 4 The measurement principle diagram of the winding temperature controller according to the embodiment of the utility model is schematically shown.

[0023] Description of reference numerals:

[0024] 1- Error measurement device;

[0025] 11-Mounting frame;

[0026] 111- base;

[0027] 112- back plate;

[0028] 113-installation part;

[0029] 114- support member;

[0030] 115-Universal wheel;

[0031] 12- Constant temperature component;

[0032] 121-housing;

[0033] 122-constant temperature bath;

[0034] 123-standard temperature display unit;

[0035] 13- Standard thermometer;

[0036] 14-AC constant current source;

[0037] 15-AC ammeter;

[0038] 16- DC ammeter;

[0039] 17-Electric contact display;

[0040] 18- first terminal;

[0041] 19- second terminal;

[0042] 101- third terminal;

[0043] 2- Winding thermostat;

[0044] 21-display unit;

[0045] 22-temperature sensing unit;

[0046] 23- Heating wire;

[0047] 24-current on;

[0048] 25-operation unit;

[0049] 3- Transformer;

[0050] 31-winding;

[0051] 32-Current transformer. DETAILED DESCRIPTION

[0052] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention, and the various features described in the embodiments can be combined to form multiple optional solutions. It should also be noted that, for ease of description, only the parts related to the present invention are shown in the accompanying drawings, rather than all structures.

[0053] Figure 1 The system diagram of the error measuring device of the transformer winding temperature controller according to the embodiment of the utility model is schematically shown. Figure 2 A three-dimensional diagram schematically shows an error measuring device for a transformer winding temperature controller according to an embodiment of the utility model, Figure 3 A second perspective stereogram of an error measuring device for a transformer winding temperature controller according to an embodiment of the utility model is schematically shown.

[0054] As one aspect of the embodiment of the utility model, a device for measuring the error of a transformer winding temperature controller is provided. Figure 1 As shown, the winding temperature controller 2 to be tested includes a temperature sensing unit 22, a display unit 21, a current output terminal and a temperature switch. The display unit 21 is coupled to the temperature sensing unit 22 and is suitable for displaying the measured temperature measured by the temperature sensing unit. The current output terminal is suitable for outputting a current signal related to the measured temperature, and the temperature switch is configured to switch the switch state in response to the measured temperature exceeding the set temperature. Figure 2 and Figure 3 As shown, the error measuring device 1 includes a mounting frame 11, a thermostat component 12, a standard thermometer 13 and a measuring component. The thermostat component 12 is mounted on the mounting frame 11 and is suitable for simulating the working environment of the winding of the transformer. The temperature sensing unit 22 is inserted into the thermostat component 12. The standard thermometer 13 is inserted into the thermostat component 12 and is suitable for obtaining the temperature of the thermostat component 12 to determine whether the winding temperature controller is qualified based on the difference between the temperature of the thermostat component and the measured temperature. The measuring component is mounted on the mounting frame 11 and is suitable for displaying the output value of the current signal and displaying the remote temperature according to the output value, and recording the measured temperature at the switching time.

[0055] According to the error measuring device of the transformer winding temperature controller of the embodiment of the utility model, by integrating the thermostat component and the measuring component on the mounting frame, multiple indicators of the transformer winding temperature controller can be measured, the complexity of the system is reduced, the maintenance difficulty of the error measuring device is reduced and the measurement process is simplified. The thermostat component provides a constant temperature environment to avoid the influence of temperature changes in the external environment. A standard thermometer is set in the thermostat component, and the temperature of the thermostat component is detected by the standard thermometer. Then, in the process of measuring the error of the winding temperature controller to be measured, the output value of the current signal at the current output end of the winding temperature controller is measured and displayed by the measuring component. According to the linear relationship between the output value and the temperature value, the output value can be converted into a temperature value, and then the temperature value is compared with the temperature of the thermostat component, and the remote error between the output value and the temperature of the thermostat component can be obtained; according to the comparison of the measured temperature displayed by the display unit of the winding temperature controller and the temperature of the thermostat component detected by the standard thermometer, the difference between the measured temperature and the temperature of the thermostat component can be obtained, and the difference is used as the indication error. By measuring and recording the measured temperature of the temperature switch when the measured temperature is near the set temperature and the temperature switch is switched, the switching error of the temperature switch can be obtained. According to the standard error range of the winding temperature controller, it can be judged whether the winding temperature controller to be tested is qualified.

[0056] Furthermore, when the indication error, remote error and switching error are all within the standard error range of the winding temperature controller, the winding temperature controller is qualified; when one of the indication error, remote error and switching error exceeds the standard error range of the winding temperature controller, the winding temperature controller is unqualified.

[0057] Figure 4 The measurement principle diagram of the winding temperature controller according to the embodiment of the utility model is schematically shown.

[0058] like Figure 4 As shown, the transformer winding temperature controller (winding temperature controller) is an instrument specially used to measure the temperature of the winding 31 of the transformer 3 and output a control signal, and is mainly composed of an oil level temperature controller (that is, a temperature sensing unit 22), a thermal simulation device (that is, a heating wire 23), a current output terminal and a temperature switch.

[0059] The working principle of the winding temperature controller is to place the temperature sensing element 23 of the winding temperature controller in the special measuring hole of the top layer of the oil tank of the transformer 23. When the oil temperature of the transformer 23 changes, the pressure of the temperature sensing medium in the pressure-type temperature package in the temperature sensing element 23 changes with the temperature, causing the elastic element to produce a corresponding displacement, and the pointer of the indicating instrument of the display unit 21 rotates. When the load of the transformer 3 is zero, the temperature value indicated by the winding temperature controller 2 is the top layer oil temperature of the transformer 3. When the transformer 3 is loaded, an additional temperature rise is generated on the oil, and a current proportional to the load is taken out through the current transformer 32 of the transformer 3. After adjustment by the converter, it flows through the heating wire 23 embedded in the temperature sensing element 23 to generate heat, thereby increasing the rotation of the indicating instrument pointer. The increase is approximately equal to the additional temperature rise of the oil by the winding temperature controller. The temperature value indicated by the winding temperature controller is the sum of the top layer oil temperature of the transformer and the additional temperature rise of the oil by the winding.

[0060] In an alternative embodiment, the display unit of the winding temperature controller may also be of other types, such as a digital display unit.

[0061] In an exemplary embodiment, the standard thermometer may be used as follows Figure 1 A mercury thermometer is shown, but other types of thermometers may be used, such as a platinum resistance thermometer.

[0062] According to the embodiments of the present utility model, Figures 2 to 3 As shown, the mounting frame 11 includes a base 111, a back plate 112 and a mounting portion 113. The base 111 thermostatic component is mounted on the base, the back plate 112 extends upward from a first edge of the base 111, and the mounting portion 113 extends horizontally from the upper portion of the back plate 112 toward a second edge of the base 111 opposite to the first edge, and forms a receiving cavity with the back plate 112. The measuring component includes a DC ammeter 16, a display and an electric contact indicator 17. The DC ammeter 16 is mounted in the receiving cavity and extends outside the mounting portion 113, and is suitable for measuring and displaying the output value. The display is mounted on the mounting portion, and is suitable for displaying the remote temperature based on the output value. The electric contact indicator 17 is mounted on the base 111, spaced apart from the thermostatic component 12, and electrically connected to the temperature switch, and is suitable for recording the measured temperature at the switching moment of the temperature switch.

[0063] According to an embodiment of the utility model, the current signal output by the current output terminal is correlated with the measured temperature (for example, a linear relationship), and a remote temperature value represented by the current signal can also be obtained by artificial calculation, thereby comparing the remote temperature value with the temperature of the constant temperature component to determine whether the current signal output by the current output terminal is within the error range.

[0064] According to the embodiment of the present utility model, the DC ammeter 16 and the display can be designed as one piece or can be provided separately.

[0065] In an exemplary embodiment, when the DC ammeter and the display are designed as one body, the display panel can simultaneously display the output value of the current signal and the remote temperature value obtained according to the output value. It is understandable that the output value and the remote temperature value can also be displayed alternately.

[0066] According to the embodiments of the utility model, the current signal outputted from the current output terminal is correlated with the measured temperature (for example, a linear relationship). The display performs calculations based on the output value of the current signal to obtain and display a remote temperature value represented by the current signal. The remote temperature value is then compared with the temperature of the thermostatic component (difference operation) to obtain an additional error. By comparing the additional error with the standard error range of the winding temperature controller, it can be determined whether the error of the current signal outputted from the current output terminal is within the error range.

[0067] It is understandable that the above-mentioned logical calculations only require simple logic circuits to be implemented, such as a single-chip microcomputer, a CPU, etc., and there is no need to design or develop corresponding software for them. Those skilled in the art can understand, implement and reproduce them after reading the above-mentioned technical solution, and no excessive elaboration is given here.

[0068] According to an embodiment of the utility model, Figure 2 and Figure 3 As shown, the mounting frame 11 further includes a plurality of second mounting members, one end of which is mounted on the back plate 112, and the other end is mounted on the side wall of the electric contact display 17, for fixing the electric contact display 17 on the mounting frame 11. According to an embodiment of the utility model, as Figure 2 As shown, the winding temperature controller 2 also includes an operating unit 25, which is arranged below the display unit 21. The operating unit 25 includes a shell and a cover. The shell is formed below the display unit, a cavity is formed inside the shell, and the cover cooperates with the shell to close the cavity. The temperature switch is installed in the cavity.

[0069] According to the embodiments of the present utility model, Figure 2 As shown, a plurality of locks connected to the cavity are installed below the operating portion 25. In this way, external cables can be inserted into the cavity through the locks and electrically connected to the temperature switch. According to an embodiment of the utility model, the winding temperature controller 2 also includes a transmitter unit installed above the temperature sensing unit, and a plurality of temperature transmitters are arranged inside the transmitter unit. The temperature transmitter is suitable for converting the measured temperature into a current signal to be output through the current output terminal.

[0070] According to the embodiment of the utility model, the current output end is the output end of the temperature transmitter, and the output DC current signal may be a 4-20mA current signal or a 0-20mA current signal.

[0071] According to the embodiments of the present utility model, Figure 2As shown, the mounting frame 11 further includes support members 114 , which extend upward from both sides of the bottom plate 111 , respectively, and are suitable for providing support for the back plate 112 to improve the stability of the back plate.

[0072] According to an embodiment of the present invention, the support member 114 may be a rod-shaped member or a plate-shaped member.

[0073] According to an embodiment of the utility model, the thermostatic assembly 12 includes a housing 121, a thermostatic bath 122 and a heating unit. The housing 121 has a cavity formed inside and is mounted on the base 111. The top of the housing 121 has an opening. The thermostatic bath 122 contains a solution, and the thermostatic bath 122 is mounted in the cavity and is located below the opening. The heating unit is mounted in the thermostatic bath 122 and is suitable for heating the solution to keep the solution at a target temperature.

[0074] According to an embodiment of the utility model, Figure 3 As shown, the mounting frame 11 also includes a plurality of first mounting members, one end of which is mounted on the back plate 112 , and the other end of which is mounted on the shell 121 of the thermostatic component 12 , for fixing the thermostatic component on the mounting frame 11 .

[0075] According to an embodiment of the present invention, the number of the first mounting members may be two, which are respectively mounted on two opposite sides of the housing 121 to fix the housing 121 on the mounting frame 11 .

[0076] According to an embodiment of the present invention, the solution may be silicone oil. It is understandable that the solution may also be water or other liquids.

[0077] According to an embodiment of the utility model, the opening size of the top of the shell 121 is larger than the outer diameter of the temperature sensing unit and smaller than the size of the transmitter unit, so that the transmitter unit can be mounted on the top of the shell 121, and the temperature sensing unit can extend into the constant temperature bath 122 through the opening, which is convenient for measuring errors.

[0078] In an illustrative embodiment, a plurality of constant temperature chambers 122 may be disposed in the housing 121 , and a plurality of openings may be provided at the top of the housing 121 , each opening corresponding to a constant temperature chamber 122 .

[0079] According to an embodiment of the utility model, the thermostatic bath may be a small-sized thermostatic bath, such as a cube with a side length not exceeding 0.5 m, so as to reduce the overall volume of the error measuring device, so that the error measuring device can be conveniently used for on-site measurement.

[0080] According to an embodiment of the utility model, the thermostatic bath may have a rectangular parallelepiped or a columnar shape.

[0081] According to an embodiment of the utility model, the winding temperature controller 2 further includes a heating wire 23. The heating wire 23 is wound around the temperature sensing unit 22 and is suitable for generating heat to simulate the additional temperature rise of the transformer. The measuring component further includes an AC constant current source 14, which is installed in the accommodating cavity and extends outside the mounting portion 113, and is suitable for providing a working current for the winding temperature controller 2. The current switch 24 in the winding temperature controller 2 is turned, so that the current switch 24 provides a thermal simulation current to the heating wire 23 under the action of the working current.

[0082] According to an embodiment of the utility model, the error measuring device also includes an AC ammeter 15, which is installed in the accommodating cavity, extends outside the mounting portion 113, and is spaced apart from the AC constant current source 14, and is suitable for obtaining a monitoring current of the thermal simulation current.

[0083] According to the embodiment of the utility model, when the heating wire is not heated, the measured temperature displayed by the winding thermostat is the temperature of the thermostatic component obtained by the temperature sensing unit. When the heating wire is heated, the heating wire generates an additional temperature rise by passing a thermal simulation current through the heating wire, thereby increasing the rotation of the indicator instrument pointer, and the increase value is approximately equal to the additional temperature rise of the solution by the winding thermostat, and the measured temperature displayed by the display unit is the sum of the temperature of the thermostatic component obtained by the temperature sensing unit and the additional temperature rise.

[0084] The additional error can be obtained by searching the temperature rise value corresponding to the input thermal simulation current in the additional temperature rise and thermal simulation current comparison table, and then comparing the two measured temperatures with the temperature rise value.

[0085] According to the embodiment of the present utility model, the additional temperature rise and thermal simulation current comparison table is a standard comparison table, as shown in Table 1.

[0086] Table 1 Comparison table of additional temperature rise and thermal simulation current

[0087] #timg# / ℃ 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 #timg# / mA 740 800 860 920 980 1040 1090 1140 1190 1240 1280 1320 1360 1400 1440

[0088] In Table 1, Indicates the temperature rise value, is the thermal simulation current.

[0089] According to an embodiment of the utility model, when searching for a thermal simulation current corresponding to an additional temperature rise value not shown in the additional temperature rise and thermal simulation current comparison table, an interpolation method may be used for calculation.

[0090] According to the embodiment of the utility model, the thermal simulation current is monitored by the AC ammeter 15, and the thermal simulation current value of the thermal simulation current actually outputted can be obtained, so that the actual magnitude of the additional temperature rise can be determined, thereby avoiding the problem of a large additional error between the remote temperature displayed remotely according to the current output end due to the deviation of the thermal simulation current output.

[0091] According to the embodiment of the utility model, the current switch 24 is installed in the transmitter unit, cooperates with the current transmitter, and outputs the thermal simulation current.

[0092] According to an embodiment of the present invention, there may be multiple current switches 24 , each corresponding to different thermal simulation currents.

[0093] According to the embodiments of the present utility model, Figure 2 As shown, the error measuring device further includes two first terminals 18 and two second terminals 19. The two first terminals 18 are mounted on the mounting portion 113, wherein one end of one of the first terminals is electrically connected to the current switch 24, one end of the other first terminal is electrically connected to the AC ammeter 15, and the other ends of the two first terminals 18 are connected to both ends of the heating wire 23, so that the AC ammeter 15 is connected in series between the current switch 24 and the heating wire 23. The two second terminals 19 are mounted on the mounting portion 113 and spaced apart from the two first terminals, one end of the two second terminals 19 is electrically connected to the DC ammeter 16, and the other end is pluggable and electrically connected to the current output end.

[0094] According to an embodiment of the utility model, by setting two first terminals and two second terminals, it is possible to easily remove the winding temperature controller from the error measuring device after measuring the error of the winding temperature controller currently being measured, and to quickly replace the next winding temperature controller to be measured, thereby simplifying the measurement process and improving the measurement efficiency.

[0095] According to an embodiment of the utility model, there are multiple current output terminals, and the error measuring device further includes two third terminals 101 and a resistor. The two third terminals 101 are mounted on the mounting portion 113 and are spaced apart from the multiple first terminals 18. The resistor is connected across the two third terminals 101 and is suitable for converting one of the current signals into a voltage signal.

[0096] According to an embodiment of the present invention, the mounting frame 11 further includes a plurality of universal wheels 115 , and the plurality of universal wheels 115 are mounted on the bottom plate of the base 111 .

[0097] In an illustrative embodiment, Figure 3 As shown, there are four universal wheels 115 , which are respectively mounted on the bottom plate of the base 111 .

[0098] According to the embodiment of the utility model, by providing a mounting frame 11, the constant temperature component 12, the standard thermometer 13, the AC constant current source 14, the AC ammeter 15, the DC ammeter 16, the electric contact display 17, the first terminal 18, the second terminal 19 and the third terminal 101 can be integrated, which simplifies the measurement process, can improve the efficiency of the error measurement of the winding temperature controller, and reduce the difficulty of maintaining the error measurement device.

[0099] According to the embodiment of the utility model, the method of comparing with the standard thermometer can be used for measurement. The standard thermometer and the temperature sensing unit of the winding temperature controller to be measured are inserted into the thermostatic bath, and the temperature in the thermostatic bath is controlled not to deviate from the calibration point ±0.5°C. The reading of the standard thermometer is used as the standard. After the temperature displayed by the standard thermometer stabilizes, the indication value changes by no more than 0.2 / 10min. At the same time, the indication values ​​of the standard thermometer, the winding temperature controller and the DC ammeter are read and recorded. When reading the indication value of the winding temperature controller, the line of sight should be perpendicular to the dial, and the reading should be estimated to 1 / 10 of the scale value. In this way, according to the recorded measured temperature, the temperature of the thermostatic component and the output value of the DC ammeter, the indication error and the remote error can be obtained respectively.

[0100] Then, turn the current switch on the winding temperature controller to select the output thermal simulation current so that the heating wire generates additional temperature rise under the action of the thermal simulation current. After the measured temperature stabilizes, read the measured temperature. According to the additional temperature rise and thermal simulation current comparison table, find the temperature rise value corresponding to the selected thermal simulation current, and compare the difference between the measured temperature at this time and the temperature of the constant temperature component with the temperature rise value to obtain the additional error.

[0101] By controlling the temperature of the thermostatic component, the measured temperature is made close to the set temperature of the temperature switch, and then the switching times of the temperature switch and the measured temperature at the switching moment of the temperature switch are recorded through the electric contact display, and the error of the temperature switch is measured.

[0102] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An error measuring device for a transformer winding temperature controller, characterized in that: The winding temperature controller (2) to be tested comprises: Temperature sensing unit (22); A display unit (21), coupled to the temperature sensing unit (22), and adapted to display a measured temperature measured by the temperature sensing unit (22); a current output terminal adapted to output a current signal related to the measured temperature; and a temperature switch configured to switch a switch state in response to the measured temperature exceeding a set temperature; The error measuring device (1) comprises: Mounting frame (11); A constant temperature component (12) is mounted on the mounting frame (11) and is suitable for simulating the working environment of a transformer winding, and the temperature sensing unit (22) is inserted into the constant temperature component (12); a standard thermometer (13), inserted in the thermostatic component (12), adapted to obtain the temperature of the thermostatic component (12), so as to judge whether the winding temperature controller is qualified based on the difference between the temperature of the thermostatic component (12) and the measured temperature; and A measuring component is mounted on the mounting frame (11), and is suitable for displaying the output value of the current signal and displaying the remote temperature according to the output value, and recording the measured temperature at the switching moment.

2. The error measuring device according to claim 1, characterized in that: The mounting frame (11) comprises: A base (111), the thermostatic component being mounted on the base; A back plate (112) extending upward from a first edge of the base (111); and A mounting portion (113) extending horizontally from an upper portion of the back plate (112) toward a second edge of the base (111) opposite to the first edge, and forming a receiving cavity between the mounting portion and the back plate (112); The measuring assembly comprises: A direct current ammeter (16), installed in the accommodating cavity and extending outside the mounting portion (113), suitable for measuring and displaying the output value; a display, mounted on the mounting portion, adapted to display the remote temperature based on the output value; and An electric contact display (17) is mounted on the base (111), spaced apart from the thermostatic component (12), and electrically connected to the temperature switch, and is suitable for recording the measured temperature at the switching moment of the temperature switch.

3. The error measuring device according to claim 2, characterized in that: The mounting frame (11) further comprises: A support member (114) is installed between the base (111) and the mounting portion (113), and is suitable for providing support for the mounting portion (113).

4. The error measuring device according to claim 2, characterized in that: The constant temperature component (12) comprises: A shell (121) having a cavity formed therein and mounted on the base (111); an opening is formed at the top of the shell (121); A constant temperature tank (122) containing a solution, the constant temperature tank (122) being installed in the cavity and located below the opening; and A heating unit, installed in the constant temperature bath (122), adapted to heat the solution so that the solution maintains a target temperature; Wherein, the temperature sensing unit (22) extends from the opening into the constant temperature bath (122).

5. The error measuring device according to claim 4, characterized in that: The thermostatic component (12) further comprises: A standard temperature display unit (123) is mounted on the housing (121), is electrically connected to the standard thermometer and the heating unit, and is suitable for setting the target temperature and displaying the temperature of the constant temperature component (12).

6. The error measuring device according to claim 2, characterized in that: The winding temperature controller (2) further comprises: A heating wire (23) wound around the temperature sensing unit (22) and adapted to generate heat to simulate an additional temperature rise of the transformer; The measuring component also includes: an AC constant current source (14), installed in the accommodating cavity and extending outside the mounting portion (113), suitable for providing a working current for the winding temperature controller (2); The current switch (24) in the winding temperature controller (2) is turned so that the current switch (24) provides a thermal simulation current to the heating wire (23) under the action of the working current.

7. The error measuring device according to claim 6, characterized in that: The measurement kit also includes: An AC ammeter (15) is installed in the accommodating cavity, extends outside the mounting portion (113), and is spaced apart from the AC constant current source (14), and is suitable for obtaining a monitoring current of the thermal simulation current.

8. The error measuring device according to claim 7, characterized in that: Also includes: Two first terminals (18) are mounted on the mounting portion (113), wherein one end of one of the first terminals is electrically connected to the current switch (24), one end of the other first terminal is electrically connected to the AC ammeter (15), and the other ends of the two first terminals (18) are connected to both ends of the heating wire (23), so that the AC ammeter (15) is connected in series between the current switch (24) and the heating wire (23); Two second terminals (19) are mounted on the mounting portion (113) and are spaced apart from the two first terminals; one end of the two second terminals (19) is electrically connected to the DC ammeter (16), and the other end is pluggably electrically connected to the current output end.

9. The error measuring device according to claim 8, characterized in that: There are multiple current output terminals, and the error measuring device further includes: Two third terminals (101) are mounted on the mounting portion (113) and are spaced apart from the two first terminals (18); The resistor is connected between the two third terminals (101) and is suitable for converting one of the current signals into a voltage signal.

10. The error measuring device according to any one of claims 2 to 9, characterized in that: The mounting frame (11) further comprises: A plurality of universal wheels (115) are mounted on the bottom plate of the base (111).

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