Transformer temperature control method and transformer

文档序号：1112435 发布日期：2020-09-29 浏览：10次中文

阅读说明：本技术 一种变压器温度控制方法及变压器 (Transformer temperature control method and transformer ) 是由陈欢林先明刘利权于 2019-03-18 设计创作，主要内容包括：本发明公开了一种变压器温度控制方法,包括：根据变压器的顶层油温开启风机组进行降温；根据所述顶层油温及所述变压器的当前负荷确定是否需要启动冷却器组油泵；测量运行中的变压器冷却器组油泵的当前设备温度；根据冷却器组油泵的当前设备温度确定油泵电机的频率变化指令；判断此时的油泵频率是否达到频率阈值；判断此时顶层油温是否大于上限温度；根据所述冷却器组油泵的当前设备温度以及当前启动风扇的数量,确定所述冷却器组油泵的散热功率,并对所述散热功率进行额定修正,根据所述额定修正后的散热功率确定所述冷却器的散热效率,根据修正后的冷却器散热效率与预设的散热效率下限值,输出报警信号；根据顶层油温确定启动油泵的数量。(The invention discloses a transformer temperature control method, which comprises the following steps: starting a fan unit to cool according to the top oil temperature of the transformer; determining whether an oil pump of a cooler group needs to be started or not according to the top oil temperature and the current load of the transformer; measuring the current equipment temperature of an oil pump of a transformer cooler group in operation; determining a frequency change instruction of an oil pump motor according to the current equipment temperature of an oil pump of a cooler group; judging whether the frequency of the oil pump reaches a frequency threshold value or not; judging whether the top oil temperature is higher than the upper limit temperature or not; determining the heat dissipation power of the cooler oil pump according to the current equipment temperature of the cooler oil pump and the number of the current starting fans, performing rated correction on the heat dissipation power, determining the heat dissipation efficiency of the cooler according to the heat dissipation power after the rated correction, and outputting an alarm signal according to the heat dissipation efficiency of the cooler after the correction and a preset lower limit value of the heat dissipation efficiency; and determining the number of the starting oil pumps according to the top oil temperature.)

1. A method for controlling the temperature of a transformer, the method comprising the steps of:

s1: starting a fan unit to cool according to the top oil temperature of the transformer;

s2: acquiring the top oil temperature of the transformer, the current load of the transformer and the ambient temperature again, wherein the ambient temperature is the temperature of the working environment of the transformer; determining whether an oil pump of a cooler group needs to be started according to the top oil temperature and the current load of the transformer, if so, continuing the step S3, otherwise, transferring to S11;

s3: starting a working cooler group oil pump, wherein the maximum frequency of a frequency converter of the working cooler group oil pump is limited to fmax, the initial frequency of the frequency converter of the working cooler group oil pump is f1, and at the moment, the frequency converter of the working cooler group oil pump operates at the initial frequency of f1 and operates at a constant frequency and a constant speed;

s4: measuring the current equipment temperature of an oil pump of a transformer cooler group in operation;

s5: determining a frequency change instruction of an oil pump motor according to the current equipment temperature of an oil pump of a cooler group, and sending the frequency change instruction to the oil pump motor to control the oil pump motor to drive the oil pump to operate;

s6: judging whether the frequency of the oil pump reaches a frequency threshold value, if so, executing S7, and if not, executing S8;

s7: judging whether the top oil temperature is higher than the upper limit temperature or not, judging whether the transformer is in an overload or winding overtemperature state or not, if so, inputting all fan sets which are in an automatic state and do not operate, and if not, cutting off the fan sets which are input due to the winding overtemperature, and then executing S9;

s8: correcting the ambient temperature of the current equipment temperature of the oil pump of the cooler group, and then returning to S6;

s9: determining the heat dissipation power of the cooler oil pump according to the current equipment temperature of the cooler oil pump and the number of the current starting fans, performing rated correction on the heat dissipation power, determining the heat dissipation efficiency of the cooler according to the heat dissipation power after the rated correction, and outputting an alarm signal according to the heat dissipation efficiency of the cooler after the correction and a preset lower limit value of the heat dissipation efficiency;

s10: determining the number of starting oil pumps according to the top oil temperature;

s11: monitoring the ambient temperature, detecting the temperature through a second temperature sensor arranged on the inner side of the side wall of the oil-immersed transformer, wherein the second temperature sensor rotates around an output shaft of the motor under the driving of the motor, and the time for rotating the output shaft of the motor for one circle is N2 seconds;

s12: acquiring a second temperature sensor detection value at the current time every N2 seconds, and acquiring a first predicted temperature value of a first future time period after the current time and a second predicted temperature value of a second future time period after the first future time period in a pre-stored temperature prediction table through the second temperature sensor detection value at the current time to obtain a predicted temperature change trend from the first future time period to the second future time period;

s13: performing rated correction on the heat dissipation power according to the predicted temperature change trend;

s14: judging whether the current predicted heat dissipation power is enough to cool down, if so, executing S15, and if not, executing S16;

s15: when the oil temperature of the top layer of the transformer is lower than the oil temperature lower limit, cutting off the fan set with the longest accumulated operation time, and if the oil temperature of the top layer of the transformer is still lower than the oil temperature lower limit, continuously cutting off the next fan set with the longest accumulated operation time, and sequentially cutting off the last fan set;

s16: acquiring a first historical time corresponding to the first future time in historical dates, predicting to acquire a first predicted load value of the transformer corresponding to the first future time based on a first historical load average value of the first historical time, a first load comprehensive influence rate of the first historical time with the predicted temperature gear, and a first historical load value of the first historical time of the first historical date corresponding to the first future date of the first future time, and then executing S6.

2. The transformer temperature control method according to claim 1, wherein the S1 includes:

s11': detecting the temperature of top oil in an oil tank through a first temperature sensor in the transformer oil tank;

s12': and if the average temperature of the top layer oil in the oil tank detected in N1 seconds is greater than the preset upper limit temperature, the controller acquires the running accumulated time of all fans of the fan set, and the fan set with the longest accumulated stop time is thrown into for cooling.

3. The transformer temperature control method according to claim 1, wherein the S10 includes:

s101: detecting a top layer oil temperature, and starting n1 groups of oil pumps when the top layer oil temperature is in a temperature interval (T1 ', T1 ' + n1 delta T1), wherein T1 ' represents a first temperature threshold value, delta T1 represents a set first temperature rise value, and n1 represents a positive integer;

s102: every X seconds, respectively calculating the average value of all first top layer oil temperature values and all second top layer oil temperature values counted in the previous X seconds, and respectively recording the calculated average value of the first top layer oil temperature values and the calculated average value of the second top layer oil temperature values as a first calculated value and a second calculated value;

s103: starting the n2 groups of oil pumps when the mean value of the first and second calculated values is in a temperature interval (T1 ', T1 ' + n2 Δ T2), wherein T1 ' represents a first temperature threshold, Δ T2 represents a set second temperature rise and Δ T2< Δ T1, n2 represents a positive integer;

s104: and comparing the second calculated value with a preset maximum allowable oil temperature value, and outputting an oil temperature abnormal signal if the second calculated value exceeds the maximum allowable oil temperature value.

4. The transformer temperature control method according to claim 1, wherein the S2 includes:

and judging whether the top oil temperature is greater than or equal to a first temperature threshold value or not, judging whether the current load of the transformer is greater than or equal to 0.8 time of the rated load of the transformer or not, and if so, judging that the oil pump of the cooler group needs to be started.

5. The transformer temperature control method according to claim 1, wherein in S5, the frequency change command of the oil pump motor is: increasing Δ f every 1 second frequency in increments of Δ f, wherein: Δ f ═ T0+ T1)/Ta × f1, T0 is the temperature of the outer wall of the oil inlet pipe of the oil pump of the cooler group, T1 is the temperature of the outer wall of the oil return pipe, and Ta is the temperature of the cooling oil tank.

6. The transformer temperature control method according to claim 1, wherein the S5 includes: and detecting the change delta f of the frequency of the working cooler group oil pump when any one of the current equipment temperatures of the cooler group oil pump changes by 1 ℃.

7. The transformer temperature control method according to claim 1, wherein in S8, the ambient temperature is collected, and the ambient temperature is used to correct the current equipment temperature of the oil pump of the cooler group, in a specific manner:

when the environment temperature is in a first temperature range, correcting the current equipment temperature of the oil pump of the cooler group to be 1.2 of the current equipment temperature of the original oil pump of the cooler group; when the environment temperature is in a first temperature range, correcting the current equipment temperature of the oil pump of the cooler group to be 1.5 of the current equipment temperature of the original oil pump of the cooler group; and when the ambient temperature is in a first temperature range, correcting the current equipment temperature of the oil pump of the cooler group to be the current equipment temperature of the original oil pump of the cooler group, wherein the maximum value of the first temperature range is less than or equal to the minimum value of a second temperature range, and the maximum value of the second temperature range is less than or equal to the minimum value of a third temperature range.

8. The transformer temperature control method according to claim 1, wherein in S8, the heat dissipation power of the oil pump of the cooler group is: and standard heat dissipation power M/[ (T0+ T1)/Ta ], wherein M is the number of the current starting fans.

9. The transformer temperature control method according to claim 1, wherein S13 includes, after extracting the first predicted temperature value and the second predicted temperature value from the local storage space, calculating a difference between the first predicted temperature value and the second predicted temperature value, and if the calculated difference is greater than 5 ℃, modifying the heat dissipation power to: standard heat dissipation power 1.2, if the calculated difference is less than 5 ℃, correcting the heat dissipation power as: standard heat dissipation power 0.9.

10. A transformer using the transformer temperature control method according to any one of claims 1 to 9.

Technical Field

The invention relates to the field of transformers, in particular to a transformer temperature control method and a transformer.

Background

A power transformer is an important electrical device in a power system, and the operation condition of the power transformer affects the safety and reliability of the power system as a whole. The transformer fault caused by the insulation aging of the transformer due to the over-temperature operation of the winding occupies a large proportion of the faults of the power system, so the measurement of the transformer oil temperature has an extremely important significance for preventing the transformer fault. At present, the measurement of the oil temperature of the power transformer is mainly realized by a transformer thermometer and related devices matched with the transformer thermometer. In the long-term operation and use process, the accuracy of the thermometer is reduced along with the use duration, so that the detection result has errors and even errors, the effective monitoring on the temperature of the transformer is lost, and a series of potential threats are generated to a power system. Therefore, the maintenance personnel need to calibrate the thermometer accurately at regular intervals. The winding temperature is the basis for the safe operation of the transformer, so the winding temperature of the transformer must be monitored in real time during the operation of the transformer. The BWR-04 type winding temperature controller used in the present electric power system is a special instrument designed for oil immersed power transformer. The transformer winding temperature T1 is the sum of the transformer top layer oil temperature T2 and the winding temperature rise Δ T (i.e., T1 is T2+ Δ T), wherein the winding temperature rise Δ T is determined by the transformer winding current, and the current of the secondary side of the current transformer is directly proportional to the winding current; the working principle of the winding temperature controller is that the winding temperature of the transformer is indirectly measured by adopting a thermal simulation method, the working principle is that the current of the secondary side of the current transformer which is in direct proportion to the load is taken out through the current transformer, the current is adjusted by the current transformer and then is input into an electric heating element in an elastic element of the winding temperature controller, the elastic element generates an additional displacement by the heat generated by the electric heating element, so that a temperature indicated value which is higher than the oil temperature by a temperature difference delta T is generated, and the winding temperature controller obtains the average indicated value of the winding temperature by the indirect method. The digital display temperature controller is arranged in the control machine room, a transmitter in the winding temperature controller converts a temperature signal into a (4-20) mA current signal, and the mA current signal is input into the digital display temperature controller, so that an operator on duty can conveniently observe the temperature of the transformer winding in the control room, and simultaneously can output the following signals as the input of the computer monitoring system according to the needs of a user. A winding thermometer used for an oil-immersed transformer belongs to a pressure type temperature instrument, the oil temperature is measured through the pressure type thermometer, the winding current is measured through TA, current signals are mechanically superposed on the basis of the oil temperature through a radiator, and a meter indicates the winding temperature and outputs remote signals. The controller generally comprises controller, matcher, secondary instrument, and the expense is higher, but practical application is less, does not generally insert non-electric quantity control loop, moreover because the easy corrosion of mechanical part, the potentiometre in the controller is fragile more, and the meter structure is complicated, the price is expensive, the maintenance degree of difficulty is big, seriously influences on-the-spot meter instruction and monitored control system temperature display.

Disclosure of Invention

An object of the present invention is to provide a transformer temperature control method and a transformer, which can effectively take cooling measures according to the top temperature and the historical temperature condition of the transformer.

Specifically, the invention is realized by the following technical scheme:

a method of transformer temperature control, the method comprising the steps of:

s1: starting a fan unit to cool according to the top oil temperature of the transformer;

s4: measuring the current equipment temperature of an oil pump of a transformer cooler group in operation;

s6: judging whether the frequency of the oil pump reaches a frequency threshold value, if so, executing S7, and if not, executing S8;

s8: correcting the ambient temperature of the current equipment temperature of the oil pump of the cooler group, and then returning to S6;

s10: determining the number of starting oil pumps according to the top oil temperature;

s13: performing rated correction on the heat dissipation power according to the predicted temperature change trend;

s14: judging whether the current predicted heat dissipation power is enough to cool down, if so, executing S15, and if not, executing S16;

Preferably, the S1 includes:

s11': detecting the temperature of top oil in an oil tank through a first temperature sensor in the transformer oil tank;

Preferably, the S10 includes:

Preferably, the S2 includes:

Preferably, in S5, the frequency change command of the oil pump motor is: increasing Δ f every 1 second frequency in increments of Δ f, wherein: Δ f ═ T0+ T1)/Ta × f1, T0 is the temperature of the outer wall of the oil inlet pipe of the oil pump of the cooler group, T1 is the temperature of the outer wall of the oil return pipe, and Ta is the temperature of the cooling oil tank.

Preferably, the S5 includes: and detecting the change delta f of the frequency of the working cooler group oil pump when any one of the current equipment temperatures of the cooler group oil pump changes by 1 ℃.

Preferably, in S8, the ambient temperature is collected, and the current equipment temperature of the oil pump of the cooler group is corrected by the ambient temperature, which specifically includes:

Preferably, in S8, the heat dissipation power of the oil pump of the cooler group is: and standard heat dissipation power M/[ (T0+ T1)/Ta ], wherein M is the number of the current starting fans.

Preferably, the step S13 includes, after extracting the first predicted temperature value and the second predicted temperature value from the local storage space, calculating a difference between the first predicted temperature value and the second predicted temperature value, and if the calculated difference is greater than 5 ℃, correcting the heat dissipation power to be: standard heat dissipation power 1.2, if the calculated difference is less than 5 ℃, correcting the heat dissipation power as: standard heat dissipation power 0.9.

A transformer uses the aforementioned transformer temperature control method.

The invention has the beneficial effects that: and cooling measures can be effectively taken according to the top layer temperature and the historical temperature condition of the transformer.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic flow chart of a transformer temperature control method according to the present invention;

FIG. 2 is a diagram illustrating the specific step of S1 in FIG. 1;

fig. 3 is a schematic diagram illustrating a specific step of S10 in fig. 1.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the invention, as detailed in the appended claims.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in this specification and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

It is to be understood that although the terms first, second, third, etc. may be used herein to describe various information, these information should not be limited to these terms. These terms are only used to distinguish one type of information from another. For example, first information may also be referred to as second information, and similarly, second information may also be referred to as first information, without departing from the scope of the present invention. The word "if" as used herein may be interpreted as "at … …" or "when … …" or "in response to a determination", depending on the context.

The present invention will be described in detail below by way of examples.

A method for controlling the temperature of a transformer, as shown in fig. 1, the method comprising the steps of:

s1: and starting the fan unit to cool according to the top oil temperature of the transformer.

S2: acquiring the top oil temperature of the transformer, the current load of the transformer and the ambient temperature again, wherein the ambient temperature is the temperature of the working environment of the transformer; and determining whether an oil pump of the cooler group needs to be started or not according to the top oil temperature and the current load of the transformer, if so, continuing to the step S3, otherwise, transferring to S11.

Specifically, whether the top oil temperature is greater than or equal to a first temperature threshold value or not is judged, whether the current load of the transformer is greater than or equal to 0.8 times of the rated load of the transformer or not is judged, and if yes, it is judged that the oil pump of the cooler group needs to be started. By adopting the comprehensive judgment mode, the operation of starting the oil pump of the cooler group can be carried out by synthesizing the conditions of the top oil temperature and the current load of the transformer.

S3: and starting the working cooler group oil pump, wherein the maximum frequency of a frequency converter of the working cooler group oil pump is limited to fmax, the initial frequency of the frequency converter of the working cooler group oil pump is f1, and at the moment, the frequency converter of the working cooler group oil pump operates at the initial frequency of f1 and operates at a constant frequency and a constant speed.

S4: and measuring the current equipment temperature of the oil pump of the running transformer cooler group.

Specifically, an oil pump temperature sensor is arranged on the cooler oil pump and used for collecting the current equipment temperature of the cooler oil pump.

In this embodiment, the current device temperature of the oil pump of the cooler group includes an oil inlet pipe outer wall temperature T0, an oil return pipe outer wall temperature T1, and a cooling oil tank temperature Ta. This embodiment sets up temperature sensor through advancing oil pipe outer wall, returning oil pipe outer wall and cooling tank and gathers the temperature of relevant position in real time to give controlling means with the temperature value passback.

S5: determining a frequency change instruction of an oil pump motor according to the current equipment temperature of an oil pump of a cooler group, and sending the frequency change instruction to the oil pump motor to control the oil pump motor to drive the oil pump to operate.

Specifically, the frequency change command of the oil pump motor is as follows: increasing Δ f every 1 second frequency in increments of Δ f, wherein:

Δf＝(T0+T1)/Ta*f1。

the oil pump motor drives the oil pump to start according to the frequency change instruction, the oil pump is accelerated to the rated rotating speed in the starting process, and the stability of oil flow in the transformer can be guaranteed, so that the safe and stable operation of the forced oil circulation air-cooled transformer is guaranteed.

In another embodiment of the present invention, the S5 includes:

s5': and detecting the change delta f of the frequency of the working cooler group oil pump when any one of the current equipment temperatures of the cooler group oil pump changes by 1 ℃.

f2 is f1+ Δ t × Δ f, where Δ t is the amount of change in the current equipment temperature of the chiller oil pump.

S6: and judging whether the oil pump frequency reaches a frequency threshold value, if so, executing S7, and if not, executing S8.

If the frequency threshold has been reached, the cooling can no longer be performed in a manner that increases the oil pump frequency, and if the frequency threshold has not been reached, the cooling can continue to be performed in a manner that increases the oil pump frequency.

S7: and judging whether the top oil temperature is higher than the upper limit temperature or not, judging whether the transformer is in an overload or winding overtemperature state or not, if so, inputting all the fan sets which are in an automatic state and do not operate, and if not, cutting off the fan sets which are input due to the winding overtemperature, and then executing S9.

S8: the ambient temperature correction is performed on the current equipment temperature of the cooler group oil pump, and thereafter, the flow returns to S6.

Gather ambient temperature, revise the current equipment temperature of cooler group oil pump with ambient temperature, the concrete mode is:

S9: determining the heat dissipation power of the cooler oil pump according to the current equipment temperature of the cooler oil pump and the number of the current starting fans, performing rated correction on the heat dissipation power, determining the heat dissipation efficiency of the cooler according to the heat dissipation power after the rated correction, and outputting an alarm signal according to the corrected heat dissipation efficiency of the cooler and a preset lower limit value of the heat dissipation efficiency.

Specifically, the heat dissipation power of the oil pump of the cooler group is as follows: the standard heat dissipation power is M/[ (T0+ T1)/Ta ], where M is the number of currently activated fans, and it can be seen from the above formula that the larger the number of currently activated fans is, the larger the heat dissipation power of the oil pump of the cooler group is corrected, and the larger (T0+ T1)/Ta is, the smaller the heat dissipation power of the oil pump of the cooler group is corrected.

S10: and determining the number of the starting oil pumps according to the top oil temperature.

S11: monitoring ambient temperature carries out temperature detection through setting up the second temperature sensor at oil-immersed transformer lateral wall inboard, and under motor drive, second temperature sensor rotates around the output shaft of motor, and the time that the motor output shaft rotated a week is N2 seconds.

S12: acquiring a second temperature sensor detection value at every N2 seconds, and acquiring a first predicted temperature value of a first future time period after the current time and a second predicted temperature value of a second future time period after the first future time period in a pre-stored temperature prediction table through the second temperature sensor detection value at the current time to obtain a predicted temperature change trend from the first future time period to the second future time period.

The method comprises the steps that a pre-stored temperature prediction table is stored in a local storage space, the pre-stored temperature prediction table records the top layer oil temperature of any time period in any day in the history within a certain time range, for example, the current time is 18:00 in 2 months and 1 day in 2019, the top layer oil temperature information of 1 day in 2 months and 1 day in 2018 to 31 days in 1 month and 2019 is stored in the local storage space, meanwhile, the time period is divided into 12 time periods in two hours every day, and the top layer oil temperature average value of each time period every day is stored in the local storage space. When the detection value of the second temperature sensor is determined, all temperature values in the next time period (i.e., the first future time period) corresponding to the value in the local storage space are searched according to the detection value of the second temperature sensor, and the mean value of all the temperature values is calculated, that is, the mean value is used as a first predicted temperature value.

S13: and carrying out rated correction on the heat dissipation power according to the predicted temperature change trend.

After extracting the first predicted temperature value and the second predicted temperature value from the local storage space, calculating a difference value between the first predicted temperature value and the second predicted temperature value, and if the calculated difference value is more than 5 ℃, correcting the heat dissipation power as follows: standard heat dissipation power 1.2, if the calculated difference is less than 5 ℃, correcting the heat dissipation power as: standard heat dissipation power 0.9.

S14: and judging whether the current predicted heat dissipation power is enough to cool down, if so, executing S15, and if not, executing S16.

When the heat dissipation power is corrected to the standard heat dissipation power 1.2, the current predicted heat dissipation power is determined to be sufficient for cooling.

S15: and when the oil temperature of the top layer of the transformer is lower than the oil temperature lower limit, cutting off the fan set with the longest accumulated operation time, and if the oil temperature of the top layer of the transformer is still lower than the oil temperature lower limit, continuously cutting off the next fan set with the longest accumulated operation time to the last fan set in sequence.

With the reduction of the oil temperature of the top layer of the transformer, the number of the fan sets which are put into the transformer is properly reduced, in the embodiment, only the fan sets are selected for cooling, and the predicted heat dissipation power is used for accepting or rejecting the fan sets, so that the accepting or rejecting method of the fan sets is more flexible.

S16: acquiring a first historical time corresponding to the first future time in historical dates, predicting to acquire a first predicted load value of the transformer corresponding to the first future time based on a first historical load average value of the first historical time, a first load comprehensive influence rate of the first historical time with the predicted temperature gear, and a first historical load value of the first historical time of the first historical date corresponding to the first future date of the first future time, and then executing S6.

The prediction of the transformer load value at the first future moment should be based on the transformer load value at the first historical moment in the historical date. The historical dates are all dates prior to the date of the current time, and in practice, the historical dates are typically a period of time prior to the current time, such as all dates in the last three years. The historical date is not only a concept of time, but also the historical load related data such as the historical load value, the temperature gear and the like should be included at each moment of each date in the historical date, namely the historical date should be the date containing the historical load related data. The first historical time is one or more times in the historical date, and the first historical time and the first future time have a certain corresponding relation. For example, the load difference between the transformer in the evening and the transformer in the early morning is significant, so if the first future time is the evening time, the first historical time should not include the early morning time, and the corresponding relationship between the first historical time and the first future time can be properly selected according to the requirement.

In an embodiment of the present invention, the S1 includes:

s11': the temperature of top oil in the oil tank is detected through a first temperature sensor in the transformer oil tank.

An air cylinder is arranged in the inner wall of the transformer oil tank, the first temperature sensor horizontally moves back and forth on the top oil level of the oil tank under the driving of the air cylinder, and the time for the piston rod of the air cylinder to stretch out and draw back once is N1 seconds; the first temperature sensor outputs a first detected temperature value every second.

In another embodiment of the present invention, two first temperature sensors detect the top layer oil temperature and are driven by the cylinder to move, that is, the two first temperature sensors are fixed on the piston rod of the cylinder, and the distance between the two first temperature sensors is 60mm, so that the two first temperature sensors can be conveniently installed, and the two first temperature sensors can keep a proper distance to simultaneously detect different positions of the top layer oil.

S12': and if the average temperature of the top layer oil in the oil tank detected in N1 seconds is greater than the preset upper limit temperature, the controller acquires the running accumulated time of all fans of the fan set, and the fan set with the longest accumulated stop time is thrown into for cooling.

Adding the fan set with the longest accumulated stop time, delaying for a certain time, checking whether the fan fails, and adding the fan set with longer accumulated stop time when the fan fails; and when the oil temperature of the top layer of the transformer is lower than the oil temperature lower limit, cutting off the fan set with the longest accumulated operation time, delaying for a certain time, if the oil temperature of the top layer of the transformer is still lower than the oil temperature lower limit, continuously cutting off the next group of air cooling devices with the longest accumulated operation time, and sequentially cutting off the last group of air cooling devices. The input of the fan is automatically controlled according to the temperature of the upper oil of the transformer, and the energy-saving operation of the fan is realized.

In an embodiment of the present invention, the S10 includes:

s101: detecting top layer oil temperature, and starting n1 groups of oil pumps when the top layer oil temperature is in a temperature interval (T1 ', T1 ' + n1 delta T1), wherein T1 ' represents a first temperature threshold value, delta T1 represents a set first temperature rising value, and n1 represents a positive integer.

S102: every X seconds, calculating the average value of all first top layer oil temperature values and all second top layer oil temperature values counted in the previous X seconds respectively, and recording the calculated average value of the first top layer oil temperature values and the calculated average value of the second top layer oil temperature values as a first calculated value and a second calculated value respectively.

S103: when the mean value of the first and second calculated values is in the temperature interval (T1 ', T1 ' + n2 Δ T2), n2 sets of oil pumps are started, wherein T1 ' represents a first temperature threshold, Δ T2 represents a set second temperature rise and Δ T2< Δ T1, n2 represents a positive integer.

S104: and comparing the second calculated value with a preset maximum allowable oil temperature value, and outputting an oil temperature abnormal signal if the second calculated value exceeds the maximum allowable oil temperature value.

The invention also provides a transformer using the transformer temperature control method.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.

13页详细技术资料下载

上一篇：一种医用注射器针头装配设备

下一篇：一种电源方舱内部环境柔性调节方法、系统及电源方舱

Transformer temperature control method and transformer

相关技术

网友询问留言