CN111562023B - Device and method for comprehensively monitoring and early warning equipment temperature in wind power plant box transformer substation cabin - Google Patents

Abstract

A device and a method for comprehensively monitoring and early warning the temperature of equipment in a box-type transformer substation cabin of a wind power plant comprise wireless temperature monitoring, wired temperature monitoring, humidity monitoring, transformer oil temperature, shell, environment temperature detection, running current and voltage monitoring and CPU running control alarm devices at different points of the equipment in the box-type transformer substation cabin, comprehensive temperature estimation calculation and three-level early warning judgment methods of historical temperature, current real-time temperature, temperature change rate, ambient temperature, humidity and running current of each running equipment are considered, temperature is quickly predicted and estimated according to the temperature historical value, real-time sampling value and temperature change rate of a certain measuring point, then comprehensive temperature calculation is carried out according to the influences of the environment temperature, the humidity and load current, finally, three-level early warning judgment formulas are formed on the basis of mutual constraint of the calculated value and time setting value, real-time prediction estimation comprehensive calculation and alarm are carried out on different temperature monitoring points of each equipment, and meanwhile, corresponding judgment and early warning are carried out on the exceeding of humidity and the exceeding of current.

Description

Device and method for comprehensively monitoring and early warning equipment temperature in wind power plant box transformer substation cabin

Technical Field

The invention relates to the technical field of wind power plant temperature early warning, in particular to a comprehensive monitoring and early warning device and method for the temperature of equipment in a box-type substation cabin of a wind power plant, which are reasonable in structure and early warning timely.

Background

The wind power plant box transformer substation generally comprises a high-voltage load switch, an isolating switch, a transformer, a low-voltage circuit breaker, a mutual inductor and main auxiliary devices, the traditional contact temperature monitoring of each device usually carries out early warning by taking the current real-time monitoring value as the basis, the conditions of historical temperature accumulation, temperature change rate, humidity, surrounding environment, operating current and the like of the device are not considered, this often results in missed optimal forecast times, resulting in forecast delays or forecast jitter or forecast values that decrease and prevent the equipment from operating at full power and efficiency, such as late forecasting without regard to temperature variation trends, the temperature may be accumulated and rapidly increased due to the forecast, which may cause more serious fire accident, and for example, the allowable contact temperature should be properly reduced when the environmental temperature is high and the load current is large, and the allowable temperature duration can be appropriately lengthened when the environmental temperature is low, such as in winter, and the load current is small, and the like.

Disclosure of Invention

The invention aims to overcome the defects of the real-time value early warning technology of equipment in the prior art, comprehensively estimates the value of the running equipment according to the historical temperature, the current real-time temperature, the temperature change rate, the ambient temperature, the humidity and the running current of the equipment, and judges the running equipment in a three-stage early warning mode, thereby ensuring the running of the equipment to be more efficient and reliable, and providing the comprehensive monitoring and early warning device and the early warning method for the temperature of the equipment in the box transformer cabin of the wind power plant, which have reasonable structure and early warning in time.

The technical scheme of the invention is realized as follows:

the device temperature comprehensive monitoring and early warning device comprises a load switch contact temperature measuring and transmitting module and an isolating switch temperature measuring and transmitting module which are arranged in a high-pressure chamber in a box-type transformer chamber, comprises a transformer oil temperature and transformer shell temperature measuring module arranged in a transformer unit, comprises a humidity monitoring module arranged in the box-type transformer chamber and an environment temperature measuring module arranged outside the box-type transformer chamber, and comprises a breaker contact temperature measuring and transmitting module, a current transformer temperature measuring module, a wireless temperature signal receiving module, a wired temperature signal A/D conversion module, a humidity signal A/D conversion module, a current-voltage measuring module, a current-voltage A/D conversion module, a switching value input and output module, a temperature comprehensive monitoring and processing module, a temperature monitoring and early warning device and a switch value input and output module, The device comprises a humidity comprehensive monitoring processing module, a current and voltage comprehensive monitoring processing module, a CPU comprehensive analysis and early warning output module and a display operation module;

load switch contact temperature measurement and emission module be connected with wireless temperature signal receiving module electricity, isolator temperature measurement and emission module be connected with wireless temperature signal receiving module electricity, transformer oil temperature and transformer case temperature measurement module and the wired temperature signal AD conversion module electricity of transformer unit be connected, install humidity monitoring module and humidity signal AD conversion module electricity in the case becomes the storehouse and be connected, humidity signal AD conversion module is connected with humidity integrated monitoring processing module electricity, install the ambient temperature measurement module outside the case becomes the storehouse and be connected with wired temperature signal AD conversion module electricity, install the circuit breaker contact temperature measurement and the emission module of low-pressure chamber in the case becomes the storehouse and be connected with wireless temperature signal receiving module electricity, current transformer temperature measurement module and wired temperature signal AD conversion module electricity be connected The circuit breaker current-voltage measuring module is electrically connected with the current-voltage A/D conversion module, the current-voltage A/D conversion module is electrically connected with the current-voltage comprehensive monitoring processing module, the wireless temperature signal receiving module and the wired temperature signal A/D conversion module are electrically connected with the temperature comprehensive monitoring processing module, the current-voltage comprehensive monitoring processing module and the switching value input/output module are electrically connected with the CPU comprehensive analysis and early warning output module, and the CPU comprehensive analysis and early warning output module is electrically connected with the operation display module.

The load switch contact temperature measuring and transmitting module comprises 6 temperature sensor components and a wireless transmitting component, wherein the 6 temperature sensor components are used for respectively measuring the temperatures of a moving contact and a static contact of the load switch, the wireless transmitting component is used for transmitting acquired temperature signals, and the transmitted temperature signals are received by the wireless temperature signal receiving module;

the isolating switch temperature measuring and transmitting module comprises 6 temperature sensor components and a wireless transmitting component, wherein the 6 temperature sensor components are used for respectively measuring the temperatures of a moving contact and a static contact of the isolating switch, the wireless transmitting component is used for transmitting the acquired temperature signals, and the transmitted temperature signals are received by the wireless temperature signal receiving module;

the transformer oil temperature and transformer shell temperature measuring module of the transformer unit comprises an oil temperature measuring sensor arranged on an oil way and temperature sensors arranged at 3 different parts of a transformer shell, wherein the temperature sensors convert temperature signals into electric signals and then send the electric signals into the wired temperature signal A/D conversion module through a lead;

the humidity monitoring module arranged in the box transformer substation cabin is provided with three humidity sensors, the three humidity sensors are respectively arranged in a high-pressure chamber, a transformer unit and a low-pressure chamber, convert humidity signals into electric signals and then send the electric signals into the humidity signal A/D conversion module through a lead; the environment temperature measuring module arranged outside the box transformer substation cabin is provided with four temperature sensors which are respectively arranged on the periphery of the box transformer substation cabin and used for converting temperature signals into electric signals and sending the electric signals to the wired temperature signal A/D conversion module;

the circuit breaker contact temperature measuring and transmitting module arranged in the low-pressure chamber in the box transformer substation comprises 6 temperature sensor parts and a wireless transmitting part, wherein the 6 temperature sensor parts are used for measuring the temperatures of a moving contact and a static contact of a circuit breaker respectively, the wireless transmitting part is used for transmitting acquired temperature signals, and the transmitted temperature signals are received by the wireless temperature signal receiving module;

the temperature measuring module of the current transformer comprises three temperature sensors, the three temperature sensors are respectively arranged on the corresponding A-phase, B-phase and C-phase mutual sensor iron core shells, the three temperature sensors convert temperature signals into electric signals and then send the electric signals into the wired temperature signal A/D conversion module through a lead;

the current and voltage measuring module of the circuit breaker comprises a three-phase current and three-phase voltage sampling circuit, and the sampling circuit converts large current and high voltage into low voltage and then sends the low voltage into the current and voltage A/D conversion module through a wire;

the switching value input part of the switching value input/output module acquires switching on/off signals of a high-voltage load switch, an isolating switch and a low-voltage chamber circuit breaker, and the switching value output part is an early warning output signal and a control signal; respectively reading the on-off states of the load switch, the isolating switch and the low-voltage circuit breaker, and storing the on-off states after signal jitter processing;

the temperature comprehensive monitoring processing module measures and stores the temperature of the equipment in real time and completes the comprehensive estimation calculation of the quick detection of the temperature of the equipment; respectively reading real-time temperature measurement values of different measurement points of a load switch, an isolating switch, a transformer, a low-voltage circuit breaker and a current transformer, and finishing real-time temperature sampling data of different equipment at different places and storing the data;

the humidity comprehensive monitoring processing module is used for measuring and calculating the humidity; the humidity signal is processed according to a smooth filtering mode of a measuring sensor signal, every 5 sampling signals are treated averagely, and each sampling time is carried out, and recursion is carried out once;

the current and voltage integrated monitoring and processing module calculates current and voltage signals in real time, samples data of three-phase current and voltage in real time, calculates effective values and phase angles of three phases according to a Fourier series algorithm, and calculates corresponding positive sequence, negative sequence and zero sequence values according to a symmetrical vector method;

the CPU comprehensive analysis early warning output module comprises equipment temperature comprehensive threshold value judgment and early warning; the method also comprises current and voltage excess value judgment and early warning, three-section type fixed value judgment is carried out on the measured current, and when the current exceeds the current fixed value, and the time also exceeds the fixed value, an alarm is carried out; the method also comprises humidity excess value judgment and early warning, and when the measured humidity constant value exceeds the set judgment value and the time limit also exceeds the value, the humidity excess value gives an alarm;

the display operation module is used for setting, inputting, displaying, inquiring and alarming data.

An early warning method of a comprehensive monitoring and early warning device for the temperature of equipment in a wind power plant box transformer substation cabin comprises the following steps:

step 1), initializing a program, respectively setting sequence memory addresses required by a plurality of temperature sensor measurement data, sequence memory addresses required by a plurality of humidity sensors, current and voltage measurement signal storage addresses, switching value input and output addresses, CPU comprehensive analysis early warning comprehensive calculation value temporary storage memory addresses, setting temperature early warning three-level fixed values of different measurement points of a load switch, an isolating switch, a transformer and a circuit breaker, setting humidity fixed values, setting current and voltage fixed values, storing early warning threshold values and fixed value addresses, setting a CPU comprehensive analysis early warning output module output signal mode, setting a historical data query and record memory, and setting a device communication mode;

step 2), measuring and storing the temperature in real time;

respectively reading real-time temperature measurement values of different measurement points of a load switch, an isolating switch, a transformer, a low-voltage circuit breaker and a mutual inductor, and finishing real-time temperature sampling data of different equipment at different places and storing the data;

step 3), the equipment temperature rapid detection comprehensive estimation calculation;

considering that the temperature of the equipment cannot be changed immediately and has a developing change trend process, an accumulative effect and a space diffusion degree, the comprehensive quick estimation calculation after the temperature of the equipment is detected is carried out according to the following method:

firstly, a temperature sensor is arranged to collect temperature data once every 20 milliseconds, and then 5 real-time sequence temperature data are collected in 100 milliseconds and are respectively recorded as t_i,t_i+1,t_i+2,t_i+3,t_i+4Then, the calculation step is:

past average temperature value of equipment:

current average temperature value of the device:

average variation of current temperature of equipment: t is_Δ＝T_m-T_P (3)

The current real-time temperature estimation value of the equipment is as follows: t ═ beta T_P+T_m+αT_Δ (4)

When the temperature is highDegree of change T_ΔWhen the temperature change trend is more than 0, namely the temperature change trend is increased, the calculation formula introduces the change trend, and when T is greater than 0_ΔWhen the speed is less than 0, the speed reduction change trend of the calculation formula is not considered; alpha is a temperature comprehensive estimation array coefficient occupied by temperature variation, the value is based on a positive feedback principle, the larger the temperature variation increment is, the larger the alpha value is but not more than 50%, and beta is a array coefficient occupied by an accumulated value and not more than 10%;

according to the principle of data first-in first-out, when new sampling data exists, the original first data is removed, a new data is added to still form a sampling data sequence, then calculation is carried out, and the steps are repeated so as to achieve the purpose of calculating and storing the real-time comprehensive estimated value of the temperature of the equipment;

secondly, according to the method of the first step, current real-time temperature estimated values of different measuring points of a load switch, a disconnecting switch, a transformer, a low-voltage circuit breaker and a mutual inductor are calculated and stored respectively;

step 4), calculating current and voltage signals in real time

Sampling data of three-phase current and voltage in real time, calculating effective values and phase angles of three phases according to a Fourier series algorithm, and calculating corresponding positive sequence, negative sequence and zero sequence values according to a symmetrical vector method;

step 5), humidity measurement and estimation calculation

The humidity signal is processed according to a smooth filtering mode of a measuring sensor signal, every 5 sampling signals are treated averagely, and each sampling is carried out once, and recursion is carried out once.

Step 6), reading and storing the switching value signal

Respectively reading the on-off states of the load switch, the isolating switch and the low-voltage circuit breaker, and storing the on-off states after signal jitter processing;

step 7), judging and early warning the comprehensive threshold value of the equipment temperature;

firstly, real-time temperature comprehensive estimation value over-value judgment early warning considering temperature change

Reading real-time temperature comprehensive estimation values T of different measuring points of load switch_FiAnd i is 1,2.. 6, when the real-time comprehensive estimation value is greater than the set overproof threshold value, the judgment is overproof, and corresponding reports are juxtaposedThe alarm information state bit is 1, and the three-level exceeding fixed value judgment and the time limit formula are respectively as follows:

T_Fi≥T_FiD1 t≥t_FiD1 (5)

T_Fi≥T_FiD2 t≥t_FiD2 (6)

T_Fi≥T_FiD3 t≥t_FiD3 (7)

in the formula: t is_FiD1Threshold value set value of first-stage temperature (exceeding equipment critical limit temperature) of ith temperature measuring point of load switch_FiD1Setting a value for the time rating level that exceeds the threshold, T_FiD2The second-stage temperature (exceeding the overheating temperature of the equipment) of the ith temperature measuring point of the load switch, namely the threshold set value of the overheating of the equipment, t_FiD2Setting a value for the time rating level that exceeds the threshold, T_FiD3The third-stage temperature (exceeding the basic temperature of the equipment) of the ith temperature measuring point of the load switch, namely the threshold set value of the overtemperature of the equipment, t_FiD3Setting a value for the time rating level that exceeds the threshold;

② comprehensive temperature early warning judgment considering influence of environment temperature, humidity and load current

Considering that the temperature of the load switch is in direct proportion to the load current passing through the load switch, and introducing the load current to examine a proportionality coefficient in the temperature over-value judgment, namely, the larger the load current is, the higher the allowable switch temperature is, but the larger the load current is, the higher the switch temperature is, and the shorter the allowable time after the load current exceeds a preset fixed value is; considering that the ambient temperature and humidity also have certain influence on the equipment temperature, correcting the criteria of the formulas (5), (6) and (7) to form an equipment temperature comprehensive calculation early warning judgment formula:

T_Fi≥k_Ik_Hk_ST_FiD1 t≥k_τt_FiD1 (8)

T_Fi≥k_Ik_Hk_ST_FiD2 t≥k_τt_FiD2 (9)

T_Fi≥k_Ik_Hk_ST_FiD3 t≥k_τt_FiD3 (10)

k_Icoefficient, k, proportional to the magnitude of the current_τCoefficient of proportionality, k, inversely proportional to the magnitude of the current_HCoefficient of ambient temperature, proportional to the actual ambient temperature, k_SA humidity proportionality coefficient;

when the judgment result is satisfied, the corresponding state bit of the corresponding early warning signal memory is 1;

respectively reading, calculating and judging whether the comprehensive estimated values of a plurality of temperature measuring points and the comprehensive calculated value of the equipment temperature of the isolating switch, the transformer and the low-voltage circuit breaker exceed the corresponding set thresholds according to the judging methods;

according to the judging method, after the judgment exceeds the corresponding threshold value, an alarm information state bit and an early warning signal memory state bit signal are read, when the signal state position signal is 1, the corresponding three-level over-standard early warning setting processing is rapidly carried out, the corresponding early warning information prompt is displayed on the operation display module, the corresponding alarm early warning output normally-open contact of the switching value input and output module is connected, and the alarm early warning signal lamp is flash;

step 8) judging and early warning of current and voltage excess value

Carrying out three-section type fixed value judgment on the measured current, and alarming when the current exceeds the current fixed value and the time also exceeds the fixed value;

step 9), judging and early warning humidity excess;

when the measured humidity constant value exceeds the set judgment value and the time limit also exceeds the value, alarming is carried out on the humidity excess value;

step 10), historical storage and record storage of data;

storing all state quantities and data quantities of all memories for calculation, alarm and standard exceeding marks into a memory initially set by a program for historical record and query;

step 11), the program returns online.

And returning the program to the online setting position on line for next calculation and judgment, and circulating the steps to form comprehensive monitoring calculation, judgment, alarm and emergency task processing of the equipment temperature in the wind power plant box transformer substation.

The invention has the positive effects that: the defects of the existing real-time value early warning technology are overcome, the historical temperature, the current real-time temperature, the temperature change rate, the ambient temperature, the humidity and the running current of running equipment are considered, comprehensive estimation calculation and three-level early warning judgment are carried out, efficient, comprehensive and rapid prediction and alarm are carried out, and the more efficient and reliable running of the whole equipment in a warehouse is ensured.

Drawings

Fig. 1 is a schematic structural view of the present invention.

FIG. 2 is a schematic flow diagram of the present invention.

Detailed Description

As shown in figure 1, the comprehensive monitoring and early warning device for the equipment temperature in the box-to-substation cabin of the wind power plant comprises a load switch contact temperature measuring and transmitting module and an isolating switch temperature measuring and transmitting module which are arranged in a high-pressure chamber in the box-to-substation cabin, a transformer oil temperature and transformer shell temperature measuring module which is arranged in a transformer unit, a humidity monitoring module arranged in the box-to-substation cabin, an environment temperature measuring module arranged outside the box-to-substation cabin, a breaker contact temperature measuring and transmitting module arranged in a low-pressure chamber in the box-to-substation cabin, a current transformer temperature measuring module, a wireless temperature signal receiving module, a wired temperature signal A/D conversion module, a humidity signal A/D conversion module, a current and voltage measuring module of a breaker, a current and voltage A/D conversion module, a switching value input and output module, a comprehensive temperature monitoring and processing module, The device comprises a humidity comprehensive monitoring processing module, a current and voltage comprehensive monitoring processing module, a CPU comprehensive analysis and early warning output module and a display operation module.

The load switch contact temperature measuring and transmitting module is electrically connected with the wireless temperature signal receiving module and comprises 6 temperature sensor components and a wireless transmitting component, the 6 temperature sensor components respectively measure the temperatures of a moving contact and a static contact of the load switch, the wireless transmitting component transmits the acquired temperature signals, and the transmitted temperature signals are received by the wireless temperature signal receiving module;

the isolating switch temperature measuring and transmitting module is electrically connected with the wireless temperature signal receiving module and comprises 6 temperature sensor components and a wireless transmitting component, the 6 temperature sensor components measure the temperatures of a moving contact and a static contact of the isolating switch respectively, the wireless transmitting component transmits the acquired temperature signals, and the transmitted temperature signals are received by the wireless temperature signal receiving module.

The transformer oil temperature and transformer shell temperature measuring module of the transformer unit is electrically connected with the wired temperature signal A/D conversion module, the transformer oil temperature and transformer shell temperature measuring module of the transformer unit comprises an oil temperature measuring sensor installed on an oil way and temperature sensors installed at 3 different positions of a transformer shell, the temperature sensors convert temperature signals into electric signals, and then the electric signals are sent into the wired temperature signal A/D conversion module through a lead.

The humidity monitoring module arranged in the box transformer substation cabin is electrically connected with the humidity signal A/D conversion module, and the humidity signal A/D conversion module is electrically connected with the humidity comprehensive monitoring processing module; the humidity monitoring module arranged in the box transformer substation cabin is provided with three humidity sensors, the three humidity sensors are respectively arranged in a high-pressure chamber, a transformer unit and a low-pressure chamber, a humidity signal is converted into an electric signal, and then the electric signal is sent into the humidity signal A/D conversion module through a lead.

The environment temperature measuring module arranged outside the box transformer substation cabin is electrically connected with the wired temperature signal A/D conversion module, the environment temperature measuring module arranged outside the box transformer substation cabin is provided with four temperature sensors which are respectively arranged around the box transformer substation cabin and convert temperature signals into electric signals to be sent into the wired temperature signal A/D conversion module.

The temperature measurement and emission module of the circuit breaker contact installed in the low-pressure chamber in the box transformer substation is electrically connected with the wireless temperature signal receiving module, the temperature measurement and emission module of the circuit breaker contact comprises 6 temperature sensor components and a wireless emission component, the 6 temperature sensor components measure the temperatures of a moving contact and a static contact of the circuit breaker respectively, the wireless emission component emits collected temperature signals, and the emitted temperature signals are received by the wireless temperature signal receiving module.

The current transformer temperature measurement module is electrically connected with the wired temperature signal A/D conversion module, the current transformer temperature measurement module comprises three temperature sensors, the three temperature sensors are respectively installed on the corresponding A-phase, B-phase and C-phase mutual sensor iron core shells, the three temperature sensors convert the temperature signals into electric signals, and then the electric signals are sent into the wired temperature signal A/D conversion module through a wire.

The current and voltage measuring module of the circuit breaker is electrically connected with the current and voltage A/D conversion module, the current and voltage A/D conversion module is electrically connected with the current and voltage comprehensive monitoring and processing module, the current and voltage measuring module of the circuit breaker comprises a three-phase current sampling circuit and a three-phase voltage sampling circuit, the sampling circuit converts large current and high voltage into low voltage, and then the low voltage is sent into the current and voltage A/D conversion module through a wire.

The temperature comprehensive monitoring processing module measures and stores the temperature of the equipment in real time and completes the comprehensive evaluation calculation of the quick detection of the temperature of the equipment; and respectively reading real-time temperature measurement values of different measurement points of the load switch, the isolating switch, the transformer, the low-voltage circuit breaker and the current transformer, and finishing real-time temperature sampling data of different equipment and different places and storing the data.

The humidity comprehensive monitoring processing module is used for measuring and calculating the estimated value of the humidity; the humidity signal is processed according to a smooth filtering mode of a measuring sensor signal, every 5 sampling signals are treated averagely, and each sampling is carried out once, and recursion is carried out once.

The current and voltage integrated monitoring and processing module calculates current and voltage signals in real time, samples data of three-phase current and voltage in real time, calculates effective values and phase angles of three phases according to a Fourier series algorithm, and calculates corresponding positive sequence, negative sequence and zero sequence values according to a symmetrical vector method.

The CPU comprehensive analysis early warning output module comprises equipment temperature comprehensive threshold value judgment and early warning; the method also comprises current and voltage excess value judgment and early warning, three-section type fixed value judgment is carried out on the measured current, and when the current exceeds the current fixed value, and the time also exceeds the fixed value, an alarm is carried out; and the method also comprises humidity excess value judgment and early warning, and when the measured humidity constant value exceeds the set judgment value and the time limit also exceeds the set judgment value, the humidity excess value gives an alarm.

The display operation module is used for setting, inputting, displaying, inquiring and alarming and displaying data.

The wireless temperature signal receiving module and the wired temperature signal A/D conversion module are electrically connected with the temperature comprehensive monitoring and processing module, the current and voltage comprehensive monitoring and processing module and the switching value input and output module are electrically connected with the CPU comprehensive analysis and early warning output module, and the CPU comprehensive analysis and early warning output module is electrically connected with the operation display module. The switching value input part acquires switching on-off signals of the high-voltage load switch, the isolating switch and the low-voltage chamber circuit breaker, and the switching value output part outputs early warning output signals and control signals.

As shown in fig. 2, an early warning method of a device temperature comprehensive monitoring early warning device in a wind power plant box transformer substation cabin comprises the following steps:

step 1), initializing a program, respectively setting sequence memory addresses required by a plurality of temperature sensor measurement data, sequence memory addresses required by a plurality of humidity sensors, current and voltage measurement signal storage addresses, switching value input and output addresses, CPU comprehensive analysis early warning comprehensive calculation value temporary storage memory addresses, setting temperature early warning three-level fixed values of different measurement points of a load switch, an isolating switch, a transformer and a circuit breaker, setting humidity fixed values, setting current and voltage fixed values, storing early warning threshold values and fixed value addresses, setting a CPU comprehensive analysis early warning output module output signal mode, setting a historical data query and record memory, and setting a device communication mode;

step 2), measuring and storing the temperature in real time;

respectively reading real-time temperature measurement values of different measurement points of a load switch, an isolating switch, a transformer, a low-voltage circuit breaker and a mutual inductor, and finishing real-time temperature sampling data of different equipment at different places and storing the data;

step 3), the equipment temperature rapid detection comprehensive estimation calculation;

considering that the temperature of the equipment cannot be changed immediately and has a developing change trend process, an accumulative effect and a space diffusion degree, the comprehensive quick estimation calculation after the temperature of the equipment is detected is carried out according to the following method:

firstly, a temperature sensor is arranged to collect temperature data once every 20 milliseconds, and then 5 real-time sequence temperature data are collected in 100 milliseconds and are respectively recorded as t_i,t_i+1,t_i+2,t_i+3,t_i+4Then, the calculation step is:

past average temperature value of equipment:

current average temperature value of the device:

average variation of current temperature of equipment: t is_Δ＝T_m-T_P (3)

The current real-time temperature estimation value of the equipment is as follows: t ═ beta T_P+T_m+αT_Δ (4)

When the temperature variation T_ΔWhen the temperature change trend is more than 0, namely the temperature change trend is increased, the calculation formula introduces the change trend, and when T is greater than 0_ΔWhen the speed is less than 0, the speed reduction change trend of the calculation formula is not considered; alpha is a temperature comprehensive estimation array coefficient occupied by temperature variation, the value is based on a positive feedback principle, the larger the temperature variation increment is, the larger the alpha value is but not more than 50%, and beta is a array coefficient occupied by an accumulated value and not more than 10%;

according to the principle of data first-in first-out, when new sampling data exists, the original first data is removed, a new data is added to still form a sampling data sequence, then calculation is carried out, and the steps are repeated so as to achieve the purpose of calculating and storing the real-time comprehensive estimated value of the temperature of the equipment;

secondly, according to the method of the first step, current real-time temperature estimated values of different measuring points of a load switch, a disconnecting switch, a transformer, a low-voltage circuit breaker and a mutual inductor are calculated and stored respectively;

step 4), calculating current and voltage signals in real time

Sampling data of three-phase current and voltage in real time, calculating effective values and phase angles of three phases according to a Fourier series algorithm, and calculating corresponding positive sequence, negative sequence and zero sequence values according to a symmetrical vector method;

step 5), humidity measurement and estimation calculation

The humidity signal is processed according to a smooth filtering mode of a measuring sensor signal, every 5 sampling signals are treated averagely, and each sampling is carried out once, and recursion is carried out once.

Step 6), reading and storing the switching value signal

Respectively reading the on-off states of the load switch, the isolating switch and the low-voltage circuit breaker, and storing the on-off states after signal jitter processing;

step 7), judging and early warning the comprehensive threshold value of the equipment temperature;

firstly, real-time temperature comprehensive estimation value over-value judgment early warning considering temperature change

Reading real-time temperature comprehensive estimation values T of different measuring points of load switch_FiAnd i is 1,2.. 6, when the real-time comprehensive estimation value is greater than a set overproof threshold value, the judgment is overproof, a corresponding alarm information state bit is juxtaposed to be 1, and the three-level overproof fixed value judgment and the time limit formula are respectively as follows:

T_Fi≥T_FiD1 t≥t_FiD1 (5)

T_Fi≥T_FiD2 t≥t_FiD2 (6)

T_Fi≥T_FiD3 t≥t_FiD3 (7)

in the formula: t is_FiD1Threshold value set value of first-stage temperature (exceeding equipment critical limit temperature) of ith temperature measuring point of load switch_FiD1Setting a value for the time rating level that exceeds the threshold, T_FiD2The second-stage temperature (exceeding the overheating temperature of the equipment) of the ith temperature measuring point of the load switch, namely the threshold set value of the overheating of the equipment, t_FiD2Setting a value for the time rating level that exceeds the threshold, T_FiD3The third-stage temperature (exceeding the basic temperature of the equipment) of the ith temperature measuring point of the load switch, namely the threshold set value of the overtemperature of the equipment, t_FiD3Setting the level for the time exceeding the thresholdFixing the value;

② comprehensive temperature early warning judgment considering influence of environment temperature, humidity and load current

Considering that the temperature of the load switch is in direct proportion to the load current passing through the load switch, and introducing the load current to examine a proportionality coefficient in the temperature over-value judgment, namely, the larger the load current is, the higher the allowable switch temperature is, but the larger the load current is, the higher the switch temperature is, and the shorter the allowable time after the load current exceeds a preset fixed value is; considering that the ambient temperature and humidity also have certain influence on the equipment temperature, correcting the criteria of the formulas (5), (6) and (7) to form an equipment temperature comprehensive calculation early warning judgment formula:

T_Fi≥k_Ik_Hk_ST_FiD1 t≥k_τt_FiD1 (8)

T_Fi≥k_Ik_Hk_ST_FiD2 t≥k_τt_FiD2 (9)

T_Fi≥k_Ik_Hk_ST_FiD3 t≥k_τt_FiD3 (10)

k_Icoefficient, k, proportional to the magnitude of the current_τCoefficient of proportionality, k, inversely proportional to the magnitude of the current_HCoefficient of ambient temperature, proportional to the actual ambient temperature, k_SA humidity proportionality coefficient;

when the judgment result is satisfied, the corresponding state bit of the corresponding early warning signal memory is 1;

respectively reading, calculating and judging whether the comprehensive estimated values of a plurality of temperature measuring points and the comprehensive calculated value of the equipment temperature of the isolating switch, the transformer and the low-voltage circuit breaker exceed the corresponding set thresholds according to the judging methods;

according to the judging method, after the judgment exceeds the corresponding threshold value, an alarm information state bit and an early warning signal memory state bit signal are read, when the signal state position signal is 1, the corresponding three-level over-standard early warning setting processing is rapidly carried out, the corresponding early warning information prompt is displayed on the operation display module, the corresponding alarm early warning output normally-open contact of the switching value input and output module is connected, and the alarm early warning signal lamp is flash;

step 8) judging and early warning of current and voltage excess value

Carrying out three-section type fixed value judgment on the measured current, and alarming when the current exceeds the current fixed value and the time also exceeds the fixed value;

step 9), judging and early warning humidity excess;

when the measured humidity constant value exceeds the set judgment value and the time limit also exceeds the value, alarming is carried out on the humidity excess value;

step 10), historical storage and record storage of data;

storing all state quantities and data quantities of all memories for calculation, alarm and standard exceeding marks into a memory initially set by a program for historical record and query;

step 11), the program returns online.

And returning the program to the online setting position on line for next calculation and judgment, and circulating the steps to form comprehensive monitoring calculation, judgment, alarm and emergency task processing of the equipment temperature in the wind power plant box transformer substation.

Claims (10)

1. The utility model provides a wind-powered electricity generation field case becomes interior equipment temperature integrated monitoring early warning device in storehouse which characterized in that: the device comprises a load switch contact temperature measuring and transmitting module arranged in a high-pressure chamber in a box transformer substation, a disconnecting switch temperature measuring and transmitting module, a transformer oil temperature and transformer shell temperature measuring module arranged in a transformer unit, a humidity monitoring module arranged in the box transformer substation, an environment temperature measuring module arranged outside the box transformer substation, a breaker contact temperature measuring and transmitting module arranged in a low-pressure chamber in the box transformer substation, a current transformer temperature measuring module, a wireless temperature signal receiving module, a wired temperature signal A/D conversion module, a humidity signal A/D conversion module, a current-voltage measuring module of a breaker, a current-voltage A/D conversion module, a switching value input and output module, a temperature comprehensive monitoring and processing module, a humidity comprehensive monitoring and processing module, a current-voltage comprehensive monitoring and processing module, The CPU comprehensive analysis and early warning output module and the display operation module;

the temperature measuring and transmitting module of the load switch contact is electrically connected with the wireless temperature signal receiving module, the temperature measuring and transmitting module of the isolating switch is electrically connected with the wireless temperature signal receiving module, the temperature measuring module of the transformer oil temperature and the transformer shell of the transformer unit is electrically connected with the wired temperature signal A/D conversion module, the humidity monitoring module arranged in the box transformer cabin is electrically connected with the humidity signal A/D conversion module, the humidity signal A/D conversion module is electrically connected with the humidity comprehensive monitoring and processing module, the environment temperature measuring module arranged outside the box transformer cabin is electrically connected with the wired temperature signal A/D conversion module, the temperature measuring and transmitting module of the breaker contact arranged in a low-pressure chamber in the box transformer cabin is electrically connected with the wireless temperature signal receiving module, and the temperature measuring module of the current transformer is electrically connected with the wired temperature signal A/D conversion module, the circuit breaker comprises a circuit breaker, a wireless temperature signal receiving module, a wired temperature signal A/D conversion module, a temperature comprehensive monitoring and processing module, a CPU comprehensive analysis and early warning output module, an operation display module, a wireless temperature signal receiving module, a wired temperature signal A/D conversion module, a wireless temperature signal receiving module, a wired temperature signal A/D conversion module, a wireless temperature comprehensive monitoring module, a wireless temperature signal receiving module, a wireless temperature signal A/D conversion module, a wireless temperature signal, a wireless temperature and a wireless temperature signal, a wireless temperature integrated monitoring module, a wireless voltage measurement module, a wireless circuit, a circuit;

the early warning method of the comprehensive monitoring and early warning device for the equipment temperature in the wind power plant box transformer substation cabin comprises the following steps:

step 1), initializing a program, respectively setting sequence memory addresses required by a plurality of temperature sensor measurement data, sequence memory addresses required by a plurality of humidity sensors, current and voltage measurement signal storage addresses, switching value input and output addresses, CPU comprehensive analysis early warning comprehensive calculation value temporary storage memory addresses, setting temperature early warning three-level fixed values of different measurement points of a load switch, an isolating switch, a transformer and a circuit breaker, setting humidity fixed values, setting current and voltage fixed values, storing early warning threshold values and fixed value addresses, setting a CPU comprehensive analysis early warning output module output signal mode, setting a historical data query and record memory, and setting a device communication mode;

step 2), measuring and storing the temperature in real time;

respectively reading real-time temperature measurement values of different measurement points of a load switch, an isolating switch, a transformer, a low-voltage circuit breaker and a mutual inductor, and finishing real-time temperature sampling data of different equipment at different places and storing the data;

step 3), the equipment temperature rapid detection comprehensive estimation calculation;

considering that the temperature of the equipment cannot be changed immediately and has a developing change trend process, an accumulative effect and a space diffusion degree, the comprehensive quick estimation calculation after the temperature of the equipment is detected is carried out according to the following method:

firstly, a temperature sensor is arranged to collect temperature data once every 20 milliseconds, and then 5 real-time sequence temperature data are collected in 100 milliseconds and are respectively recorded as t_i,t_i+1,t_i+2,t_i+3,t_i+4Then, the calculation step is:

past average temperature value of equipment:

current average temperature value of the device:

average variation of current temperature of equipment: t is_Δ＝T_m-T_P(3)

The current real-time temperature estimation value of the equipment is as follows: t ═ beta T_P+T_m+αT_Δ(4)

When the temperature variation T_ΔWhen the temperature change trend is more than 0, namely the temperature change trend is increased, the calculation formula introduces the change trend, and when T is greater than 0_ΔWhen the speed is less than 0, the speed reduction change trend of the calculation formula is not considered; alpha is a temperature comprehensive estimation value comparison coefficient occupied by the temperature variation, the value is based on a positive feedback principle, the larger the temperature variation increment is, the larger the alpha value is, but not more than 50 percentBeta is a ratio coefficient of the accumulated value, and the value is not more than 10%;

according to the principle of data first-in first-out, when new sampling data exists, the original first data is removed, a new data is added to still form a sampling data sequence, then calculation is carried out, and the steps are repeated so as to achieve the purpose of calculating and storing the real-time comprehensive estimated value of the temperature of the equipment;

secondly, according to the method of the first step, current real-time temperature estimated values of different measuring points of a load switch, a disconnecting switch, a transformer, a low-voltage circuit breaker and a mutual inductor are calculated and stored respectively;

step 4), calculating current and voltage signals in real time

Sampling data of three-phase current and voltage in real time, calculating effective values and phase angles of three phases according to a Fourier series algorithm, and calculating corresponding positive sequence, negative sequence and zero sequence values according to a symmetrical vector method;

step 5), humidity measurement and estimation calculation

The humidity signal is processed according to a smooth filtering mode of a measuring sensor signal, every 5 sampling signals are treated averagely, and each sampling time is carried out, and recursion is carried out once;

step 6), reading and storing the switching value signal

Respectively reading the on-off states of the load switch, the isolating switch and the low-voltage circuit breaker, and storing the on-off states after signal jitter processing;

step 7), judging and early warning the comprehensive threshold value of the equipment temperature;

firstly, real-time temperature comprehensive estimation value over-value judgment early warning considering temperature change

Reading real-time temperature comprehensive estimation values T of different measuring points of load switch_FiAnd i is 1,2, 6, when the real-time comprehensive estimation value is greater than a set overproof threshold value, judging that the real-time comprehensive estimation value exceeds the standard, juxtaposing a corresponding alarm information state bit as 1, and respectively adopting three-level overproof fixed value judgment and time limiting formulas as follows:

T_Fi≥T_FiD1 t≥t_FiD1 (5)

T_Fi≥T_FiD2 t≥t_FiD2 (6)

T_Fi≥T_FiD3 t≥t_FiD3 (7)

in the formula: t is_FiD1Threshold value set value, t, of the first-stage temperature of the ith temperature measuring point of the load switch_FiD1Setting a value for the time rating level that exceeds the threshold, T_FiD2The second-stage temperature of the ith temperature measuring point of the load switch, namely the threshold set value t of the overheating of the equipment_FiD2Setting a value for the time rating level that exceeds the threshold, T_FiD3Is the third-stage temperature of the ith temperature measuring point of the load switch, namely the threshold value set value t of the overtemperature of the equipment_FiD3Setting a value for the time rating level that exceeds the threshold; the first-stage temperature is higher than the critical limit temperature of the equipment, the second-stage temperature is higher than the overheat temperature of the equipment, and the third-stage temperature is higher than the basic temperature of the equipment;

② comprehensive temperature early warning judgment considering influence of environment temperature, humidity and load current

Considering that the temperature of the load switch is in direct proportion to the load current passing through the load switch, and introducing the load current to examine a proportionality coefficient in the temperature over-value judgment, namely, the larger the load current is, the higher the allowable switch temperature is, but the larger the load current is, the higher the switch temperature is, and the shorter the allowable time after the load current exceeds a preset fixed value is; considering that the ambient temperature and humidity also have certain influence on the equipment temperature, correcting the criteria of the formulas (5), (6) and (7) to form an equipment temperature comprehensive calculation early warning judgment formula:

T_Fi≥k_Ik_Hk_ST_FiD1 t≥k_τt_FiD1 (8)

T_Fi≥k_Ik_Hk_ST_FiD2 t≥k_τt_FiD2 (9)

T_Fi≥k_Ik_Hk_ST_FiD3 t≥k_τt_FiD3 (10)

k_Icoefficient, k, proportional to the magnitude of the current_τCoefficient of proportionality, k, inversely proportional to the magnitude of the current_HCoefficient of ambient temperature, proportional to the actual ambient temperature, k_SA humidity proportionality coefficient;

when the judgment result is satisfied, the corresponding state bit of the corresponding early warning signal memory is 1;

respectively reading, calculating and judging whether the comprehensive estimated values of a plurality of temperature measuring points and the comprehensive calculated value of the equipment temperature of the isolating switch, the transformer and the low-voltage circuit breaker exceed the corresponding set thresholds according to the judging methods;

according to the judging method, after the judgment exceeds the corresponding threshold value, an alarm information state bit and an early warning signal memory state bit signal are read, when the signal state position signal is 1, the corresponding three-level over-standard early warning setting processing is rapidly carried out, the corresponding early warning information prompt is displayed on the operation display module, the corresponding alarm early warning output normally-open contact of the switching value input and output module is connected, and the alarm early warning signal lamp is flash;

step 8) judging and early warning of current and voltage excess value

Carrying out three-section type fixed value judgment on the measured current, and alarming when the current exceeds the current fixed value and the time also exceeds the fixed value;

step 9), judging and early warning humidity excess;

when the measured humidity constant value exceeds the set judgment value and the time limit also exceeds the value, alarming is carried out on the humidity excess value;

step 10), historical storage and record storage of data;

storing all state quantities and data quantities of all memories for calculation, alarm and standard exceeding marks into a memory initially set by a program for historical record and query;

step 11), returning the program on line;

and returning the program to the online setting position on line for next calculation and judgment, and circulating the steps to form comprehensive monitoring calculation, judgment, alarm and emergency task processing of the equipment temperature in the wind power plant box transformer substation.

2. The device for comprehensively monitoring and early warning the temperature of equipment in the wind power plant box transformer substation cabin according to claim 1, is characterized in that: the load switch contact temperature measuring and transmitting module comprises 6 temperature sensor components and a wireless transmitting component, wherein the 6 temperature sensor components are used for measuring the temperatures of a moving contact and a static contact of the load switch respectively, the wireless transmitting component is used for transmitting acquired temperature signals, and the transmitted temperature signals are received by the wireless temperature signal receiving module.

3. The device for comprehensively monitoring and early warning the temperature of equipment in the wind power plant box transformer substation cabin according to claim 1, is characterized in that: the isolating switch temperature measuring and transmitting module comprises 6 temperature sensor components and a wireless transmitting component, wherein the 6 temperature sensor components are used for respectively measuring the temperatures of a moving contact and a static contact of the isolating switch, the wireless transmitting component is used for transmitting the acquired temperature signals, and the transmitted temperature signals are received by the wireless temperature signal receiving module.

4. The device for comprehensively monitoring and early warning the temperature of equipment in the wind power plant box transformer substation cabin according to claim 1, is characterized in that: the transformer oil temperature and transformer shell temperature measuring module of the transformer unit comprises an oil temperature measuring sensor arranged on an oil way and temperature sensors arranged at 3 different parts of a transformer shell, wherein the temperature sensors convert temperature signals into electric signals and then send the electric signals into the wired temperature signal A/D conversion module through a lead.

5. The device for comprehensively monitoring and early warning the temperature of equipment in the wind power plant box transformer substation cabin according to claim 1, is characterized in that: the humidity monitoring module arranged in the box transformer substation cabin is provided with three humidity sensors, the three humidity sensors are respectively arranged in a high-pressure chamber, a transformer unit and a low-pressure chamber, convert humidity signals into electric signals and then send the electric signals into the humidity signal A/D conversion module through a lead; the environment temperature measuring module arranged outside the box transformer substation cabin is provided with four temperature sensors which are respectively arranged on the periphery of the box transformer substation cabin and used for converting temperature signals into electric signals and sending the electric signals to the wired temperature signal A/D conversion module.

6. The device for comprehensively monitoring and early warning the temperature of equipment in the wind power plant box transformer substation cabin according to claim 1, is characterized in that: the circuit breaker contact temperature measuring and transmitting module arranged in the low-pressure chamber in the box transformer substation comprises 6 temperature sensor parts and a wireless transmitting part, wherein the 6 temperature sensor parts are used for measuring the temperatures of a moving contact and a static contact of a circuit breaker respectively, the wireless transmitting part is used for transmitting acquired temperature signals, and the transmitted temperature signals are received by the wireless temperature signal receiving module.

7. The device for comprehensively monitoring and early warning the temperature of equipment in the wind power plant box transformer substation cabin according to claim 1, is characterized in that: the current transformer temperature measurement module comprises three temperature sensors, the three temperature sensors are respectively arranged on the corresponding A-phase, B-phase and C-phase mutual sensor core shells, the three temperature sensors convert temperature signals into electric signals, and then the electric signals are sent into the wired temperature signal A/D conversion module through a lead.

8. The device for comprehensively monitoring and early warning the temperature of equipment in the wind power plant box transformer substation cabin according to claim 1, is characterized in that: the current and voltage measuring module of the circuit breaker comprises a three-phase current and three-phase voltage sampling circuit, wherein the sampling circuit converts large current and high voltage into low voltage, and then the low voltage is sent to the current and voltage A/D conversion module through a wire.

9. The device for comprehensively monitoring and early warning the temperature of equipment in the wind power plant box transformer substation cabin according to claim 1, is characterized in that: the switching value input part of the switching value input/output module acquires switching on/off signals of a high-voltage load switch, an isolating switch and a low-voltage chamber circuit breaker, and the switching value output part is an early warning output signal and a control signal; the temperature comprehensive monitoring processing module measures and stores the temperature of the equipment in real time and completes the comprehensive estimation calculation of the quick detection of the temperature of the equipment; respectively reading real-time temperature measurement values of different measurement points of a load switch, an isolating switch, a transformer, a low-voltage circuit breaker and a current transformer, and finishing real-time temperature sampling data of different equipment at different places and storing the data; the humidity comprehensive monitoring processing module is used for measuring and calculating the humidity; the humidity signal is processed according to a smooth filtering mode of a measuring sensor signal, every 5 sampling signals are treated averagely, and each sampling time is carried out, and recursion is carried out once; the current and voltage integrated monitoring and processing module calculates current and voltage signals in real time, samples data of three-phase current and voltage in real time, calculates effective values and phase angles of three phases according to a Fourier series algorithm, and calculates corresponding positive sequence, negative sequence and zero sequence values according to a symmetrical vector method; the CPU comprehensive analysis early warning output module comprises equipment temperature comprehensive threshold value judgment and early warning; the method also comprises current and voltage excess value judgment and early warning, three-section type fixed value judgment is carried out on the measured current, and when the current exceeds the current fixed value, and the time also exceeds the fixed value, an alarm is carried out; the method also comprises humidity excess value judgment and early warning, and when the measured humidity constant value exceeds the set judgment value and the time limit also exceeds the value, the humidity excess value gives an alarm; the display operation module is used for setting, inputting, displaying, inquiring and alarming data.

10. The early warning method of the comprehensive monitoring and early warning device for the temperature of the equipment in the wind power plant box transformer substation cabin according to claim 1 is characterized by comprising the following steps:

step 1), initializing a program, respectively setting sequence memory addresses required by a plurality of temperature sensor measurement data, sequence memory addresses required by a plurality of humidity sensors, current and voltage measurement signal storage addresses, switching value input and output addresses, CPU comprehensive analysis early warning comprehensive calculation value temporary storage memory addresses, setting temperature early warning three-level fixed values of different measurement points of a load switch, an isolating switch, a transformer and a circuit breaker, setting humidity fixed values, setting current and voltage fixed values, storing early warning threshold values and fixed value addresses, setting a CPU comprehensive analysis early warning output module output signal mode, setting a historical data query and record memory, and setting a device communication mode;

step 2), measuring and storing the temperature in real time;

respectively reading real-time temperature measurement values of different measurement points of a load switch, an isolating switch, a transformer, a low-voltage circuit breaker and a mutual inductor, and finishing real-time temperature sampling data of different equipment at different places and storing the data;

step 3), the equipment temperature rapid detection comprehensive estimation calculation;

considering that the temperature of the equipment cannot be changed immediately and has a developing change trend process, an accumulative effect and a space diffusion degree, the comprehensive quick estimation calculation after the temperature of the equipment is detected is carried out according to the following method:

firstly, a temperature sensor is arranged to collect temperature data once every 20 milliseconds, and then 5 real-time sequence temperature data are collected in 100 milliseconds and are respectively recorded as t_i,t_i+1,t_i+2,t_i+3,t_i+4Then, the calculation step is:

past average temperature value of equipment:

current average temperature value of the device:

average variation of current temperature of equipment: t is_Δ＝T_m-T_P(3)

The current real-time temperature estimation value of the equipment is as follows: t ═ beta T_P+T_m+αT_Δ (4)

When the temperature variation T_ΔWhen the temperature change trend is more than 0, namely the temperature change trend is increased, the calculation formula introduces the change trend, and when T is greater than 0_ΔWhen the speed is less than 0, the speed reduction change trend of the calculation formula is not considered; alpha is a temperature comprehensive estimation array coefficient occupied by temperature variation, the value is based on a positive feedback principle, the larger the temperature variation increment is, the larger the alpha value is but not more than 50%, and beta is a array coefficient occupied by an accumulated value and not more than 10%;

according to the principle of data first-in first-out, when new sampling data exists, the original first data is removed, a new data is added to still form a sampling data sequence, then calculation is carried out, and the steps are repeated so as to achieve the purpose of calculating and storing the real-time comprehensive estimated value of the temperature of the equipment;

secondly, according to the method of the first step, current real-time temperature estimated values of different measuring points of a load switch, a disconnecting switch, a transformer, a low-voltage circuit breaker and a mutual inductor are calculated and stored respectively;

step 4), calculating current and voltage signals in real time

Sampling data of three-phase current and voltage in real time, calculating effective values and phase angles of three phases according to a Fourier series algorithm, and calculating corresponding positive sequence, negative sequence and zero sequence values according to a symmetrical vector method;

step 5), humidity measurement and estimation calculation

The humidity signal is processed according to a smooth filtering mode of a measuring sensor signal, every 5 sampling signals are treated averagely, and each sampling time is carried out, and recursion is carried out once;

step 6), reading and storing the switching value signal

Respectively reading the on-off states of the load switch, the isolating switch and the low-voltage circuit breaker, and storing the on-off states after signal jitter processing;

step 7), judging and early warning the comprehensive threshold value of the equipment temperature;

firstly, real-time temperature comprehensive estimation value over-value judgment early warning considering temperature change

Reading real-time temperature comprehensive estimation values T of different measuring points of load switch_FiAnd i is 1,2, 6, when the real-time comprehensive estimation value is greater than a set overproof threshold value, judging that the real-time comprehensive estimation value exceeds the standard, juxtaposing a corresponding alarm information state bit as 1, and respectively adopting three-level overproof fixed value judgment and time limiting formulas as follows:

T_Fi≥T_FiD1 t≥t_FiD1 (5)

T_Fi≥T_FiD2 t≥t_FiD2 (6)

T_Fi≥T_FiD3 t≥t_FiD3 (7)

in the formula: t is_FiD1Threshold value set value, t, of the first-stage temperature of the ith temperature measuring point of the load switch_FiD1Setting a value for the time rating level that exceeds the threshold, T_FiD2The second-stage temperature of the ith temperature measuring point of the load switch, namely the threshold set value t of the overheating of the equipment_FiD2For time exceeding the threshold valueSet value, T_FiD3Is the third-stage temperature of the ith temperature measuring point of the load switch, namely the threshold value set value t of the overtemperature of the equipment_FiD3Setting a value for the time rating level that exceeds the threshold; the first-stage temperature is higher than the critical limit temperature of the equipment, the second-stage temperature is higher than the overheat temperature of the equipment, and the third-stage temperature is higher than the basic temperature of the equipment;

② comprehensive temperature early warning judgment considering influence of environment temperature, humidity and load current

Considering that the temperature of the load switch is in direct proportion to the load current passing through the load switch, and introducing the load current to examine a proportionality coefficient in the temperature over-value judgment, namely, the larger the load current is, the higher the allowable switch temperature is, but the larger the load current is, the higher the switch temperature is, and the shorter the allowable time after the load current exceeds a preset fixed value is; considering that the ambient temperature and humidity also have certain influence on the equipment temperature, correcting the criteria of the formulas (5), (6) and (7) to form an equipment temperature comprehensive calculation early warning judgment formula:

T_Fi≥k_Ik_Hk_ST_FiD1 t≥k_τt_FiD1 (8)

T_Fi≥k_Ik_Hk_ST_FiD2 t≥k_τt_FiD2 (9)

T_Fi≥k_Ik_Hk_ST_FiD3 t≥k_τt_FiD3 (10)

k_Icoefficient, k, proportional to the magnitude of the current_τCoefficient of proportionality, k, inversely proportional to the magnitude of the current_HCoefficient of ambient temperature, proportional to the actual ambient temperature, k_SA humidity proportionality coefficient;

when the judgment result is satisfied, the corresponding state bit of the corresponding early warning signal memory is 1;

respectively reading, calculating and judging whether the comprehensive estimated values of a plurality of temperature measuring points and the comprehensive calculated value of the equipment temperature of the isolating switch, the transformer and the low-voltage circuit breaker exceed the corresponding set thresholds according to the judging methods;

according to the judging method, after the judgment exceeds the corresponding threshold value, an alarm information state bit and an early warning signal memory state bit signal are read, when the signal state position signal is 1, the corresponding three-level over-standard early warning setting processing is rapidly carried out, the corresponding early warning information prompt is displayed on the operation display module, the corresponding alarm early warning output normally-open contact of the switching value input and output module is connected, and the alarm early warning signal lamp is flash;

step 8) judging and early warning of current and voltage excess value

Carrying out three-section type fixed value judgment on the measured current, and alarming when the current exceeds the current fixed value and the time also exceeds the fixed value;

step 9), judging and early warning humidity excess;

when the measured humidity constant value exceeds the set judgment value and the time limit also exceeds the value, alarming is carried out on the humidity excess value;

step 10), historical storage and record storage of data;

storing all state quantities and data quantities of all memories for calculation, alarm and standard exceeding marks into a memory initially set by a program for historical record and query;

step 11), returning the program on line;

and returning the program to the online setting position on line for next calculation and judgment, and circulating the steps to form comprehensive monitoring calculation, judgment, alarm and emergency task processing of the equipment temperature in the wind power plant box transformer substation.

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