CN213243548U

CN213243548U - Factory power interconnection system of thermal power factory

Info

Publication number: CN213243548U
Application number: CN202022306430.XU
Authority: CN
Inventors: 黄鹏
Original assignee: Huaneng Taicang Power Generation Co Ltd
Current assignee: Huaneng Taicang Power Generation Co Ltd
Priority date: 2020-10-16
Filing date: 2020-10-16
Publication date: 2021-05-18
Anticipated expiration: 2030-10-16

Abstract

The utility model relates to a thermal power factory uses electricity interconnected system, including No. 3 units and No. 4 units, No. 3 units are through 6 kilovolts 3A section, 6 kilovolts 3B section is connected to 6 kilovolts of desulfurization 3 sections respectively, No. 4 units are through 6 kilovolts of 4A sections, 6 kilovolts of 4B sections are connected to 6 kilovolts of desulfurization 4 sections respectively, 6 kilovolts of desulfurization 3 sections, 6 kilovolts of desulfurization 4 sections are arranged in 6 kilovolts of desulfurization electric wire collecting room, be connected with a contact switch on the 6 kilovolts of desulfurization 3 sections, be connected with a contact handcart on the 6 kilovolts of desulfurization 4 sections, the contact handcart is in the normally closed state, be connected through the tie line between contact switch and the contact handcart, 6 kilovolts of desulfurization 3 sections and 6 kilovolts of desulfurization 4 sections are through the interconnection intercommunication of tie line, the factory realizes the interconnection through the tie line between No. 3 units and No. 4 units; the utility model provides a No. 3 unit, No. 4 unit start become in 02 during maintenance in case take place the problem that tripping operation safety shut down risk is big and do not have the house service power start-up.

Description

Factory power interconnection system of thermal power factory

[ technical field ]

The utility model belongs to the technical field of the power consumption technique of power plant and specifically relates to a thermal power factory service interconnection system.

[ background art ]

At present, a high-voltage station service power supply wiring of a power plant is shown in an attached drawing 1, when a unit No. 3 and a unit No. 4 operate normally, station service power supplies required for maintaining unit operation are respectively supplied by a high-voltage transformer and a high-voltage public transformer of each unit plant, and a starting power supply and an accident standby power supply of the unit are from a number 02 starting transformer. During the maintenance period of the No. 02 starting transformer, the service power supplies of the No. 3 unit and the No. 4 unit in operation lose standby, and the service operation mode of the operation unit is weak. According to the actual condition of the station service wiring of the power plant, once the trip of the running unit occurs during the phase of starting, changing and overhauling of the No. 3 unit and the No. 4 unit, the station service power supply of the trip unit is lost, so that the safety shutdown is threatened, and the problem that the power supply is not started when the unit is restarted is also faced. In view of the above reasons, the overhaul time of starting the power plant number 02 is difficult to determine, which causes the equipment overhaul overdue phenomenon. Therefore, the reliability and flexibility of service power operation of the unit No. 3 and the unit No. 4 are in urgent need to be improved.

[ contents of utility model ]

The utility model aims at solving foretell not enough and provide a thermal power factory service interconnection system, solved No. 3 units, No. 4 units and started in case the problem that the tripping operation safety shut down risk is big and do not have the factory power to start during the maintenance in 02, promoted greatly and made No. 3 units, No. 4 units factory power reliability and flexibility.

For realizing above-mentioned purpose design a thermal power factory uses electricity interconnected system, including No. 3 unit and No. 4 unit, the required factory power of No. 3 unit operation is supplied by 3 factory hypervariates and 3 high-pressure public changes, the required factory power of No. 4 unit operation is supplied by 4 factory hypervariates and 4 high-pressure public changes, the starting power, the accident stand-by power of No. 3 unit, No. 4 unit all come from 02 number starting changes, No. 3 unit is connected to 6 kilovolts desulfurization 3 sections respectively through 6 kilovolts 3A section, 6 kilovolts 3B section, No. 4 unit is connected to 6 kilovolts 4 desulfurization sections respectively through 6 kilovolts 4A section, 6 kilovolts 4B section of desulfurization are arranged in 6 kilovolts desulfurization electric wire collecting rooms, be connected with a contact switch 101 on the 6 kilovolts 3 sections of desulfurization, be connected with a contact handcart 102 on the 6 kilovolts 4 sections of desulfurization, the contact handcart 102 is in a normally closed state, the contact switch 101 is connected with the contact handcart 102 through a

connecting line

103, 6 kilovolt desulfurization sections 3 and 6 kilovolt desulfurization sections 4 are interconnected and communicated through the connecting line 103, and the service power between the machine set No. 3 and the machine set No. 4 is interconnected through the connecting line 103.

Further, the No. 02 starting transformer is respectively connected to the 3 sections of 6 kV coal conveying and the 4 sections of 6 kV coal conveying through the 3 sections and the 4 sections of 6 kV public kilovolts, the 3 # high-voltage public transformer of the No. 3 unit is connected to the 3 sections of 6 kV public kilovolts through a power line, and the 4 # high-voltage public transformer of the No. 4 unit is connected to the 4 sections of 6 kV public kilovolts through a power line.

Further, the cabinet body of interconnection switch 101 divide into about three parts, and from top to bottom be control protection cabin 104, switch cabin 105, ground connection sword cabin 106 in proper order, switch cabin 105 is inside to be provided with 6 kilovolts of vacuum circuit breaker, 6 kilovolts of vacuum circuit breaker are used for putting through and breaking off interconnection 103.

Further, a control circuit and a protection circuit are arranged inside the control protection cabin 104, the control circuit is used for receiving an instruction of an operator to open and close the switch, the protection circuit is composed of a protection device 114, a current transformer and a voltage transformer, and the protection device 114 trips the switch to prevent the equipment from being damaged when the current transformer and the voltage transformer detect a circuit fault.

Further, an electrified indicator light 107 and an operation button indicator light 108 are arranged on the outer side of the control protection cabin 104, a temperature and humidity controller 109 is arranged in the control protection cabin 104, and the temperature and humidity controller 109 is electrically connected with the control loop and the protection loop respectively.

Further, a three-phase strong current circuit grounding knife switch is arranged inside the grounding knife compartment 106, the grounding knife switch is pulled open when the No. 3 unit and the No. 4 unit work normally, and the grounding knife switch is closed after no electricity is proved when the No. 02 starting transformer is overhauled, so that the strong current circuit is grounded.

Furthermore, a switch in-out cabin operation hole 110 and a grounding knife operation hole 111 are respectively formed in the switch cabin 105 and the grounding knife cabin 106, a switch observation window 112 is arranged on the switch cabin 105, and a grounding knife observation window 113 is arranged on the grounding knife cabin 106.

Compared with the prior art, the utility model, the connection switch is in a local split-combination mode, the operation needs to be ordered at work, and the system is in a cold standby state during the operation period of the No. 3 and No. 4 unit units; during the maintenance period of No. 02 starting transformer, if one unit trips, the service power of the tripping unit is lost, at the moment, a command is sent by a long value, all switches on a service section and a desulfurization section of the tripping unit are disconnected, a service section bus and a desulfurization section bus are vacated, the service power interconnection system of the thermal power plant is changed into a hot standby state (a contact handcart and a contact switch are pushed to a working position from an isolation/test position, a secondary loop is powered on), the desulfurization section bus is empty-charged by closing the contact switch, and the service section of the tripping unit is inverted through the desulfurization section; after the service section is powered on, gradually recovering the operation of each service load, paying attention to the fact that the current of each power supply of the operating unit does not exceed the rated value and the voltage is normal during recovery, recovering the service power self-carrying as soon as possible after the single-side starting of the tripping unit, and adopting a parallel switching mode during service power switching. To sum up: the utility model discloses utilize 3, the reserve switch position in storehouse on the 6 kilovolts of desulfurization section of No. 4 units, at 6 kilovolts of desulfurization 3, newly-increased one section cross-over connection line between 4 sections wire exchanges, solve 3, No. 4 units and start to become in case the problem that tripping operation safety shut down risk is big and do not have the house service power start during maintenance in 02, make 02 number start to become maintenance work and can develop by the courage, make 3, No. 4 units house service reliability and flexibility obtain very big promotion, be worth popularizing and applying.

[ description of the drawings ]

FIG. 1 is a wiring diagram of a power plant high-voltage service power supply before modification;

FIG. 2 shows a strong current loop of the factory power interconnection system of the thermal power plant;

FIG. 3 is a secondary circuit part of the factory power interconnection system of the thermal power plant of the present invention;

fig. 4 is a schematic connection diagram of the interconnection switch, the interconnection handcart and the interconnection line in the utility model;

fig. 5 is a schematic front view of the interconnection switch of the present invention;

in the figure: 101. the device comprises a connection switch 102, a connection handcart 103, a connection line 104, a control protection cabin 105, a switch cabin 106, a grounding knife cabin 107, a live indicator lamp 108, an operation button indicator lamp 109, a temperature and humidity controller 110, a switch cabin access operation hole 111, a grounding knife operation hole 112, a switch observation window 113, a grounding knife observation window 114 and a protection device.

[ detailed description of the invention ]

The invention is further described below with reference to the accompanying drawings:

as shown in the attached drawings, the utility model provides a thermal power factory electricity interconnection system, including No. 3 unit and No. 4 unit, the required house service power of 3 unit operation is changed by 3 factory height and 3 high-pressure public changes supply, the required house service power of 4 unit operation is changed by 4 factory height and 4 high-pressure public changes supply, 3 unit, 4 unit's starting power, accident stand-by power all come from 02 starting changes, 3 unit is connected to 6 kilovolts desulfurization 3 sections respectively through 6 kilovolts 3A section, 6 kilovolts 3B section, 4 unit is connected to 6 kilovolts 4 desulfurization 4 sections respectively through 6 kilovolts 4A section, 6 kilovolts 4B section; the No. 02 starting transformer is respectively connected to the 3 sections of 6 KV coal conveying and the 4 sections of 6 KV coal conveying through the 3 sections and the 4 sections of 6 KV public, the 3 # high-voltage public transformer of the No. 3 unit is connected to the 3 sections of 6 KV public through a power line, and the 4 # high-voltage public transformer of the No. 4 unit is connected to the 4 sections of 6 KV public through a power line; 6 kilovolt desulfurization 3 sections, 6 kilovolt desulfurization 4 sections are arranged at 6 kilovolt desulfurization electric wire collecting rooms, be connected with a tie switch 101 on 6 kilovolt desulfurization 3 sections, be connected with a tie handcart 102 on 6 kilovolt desulfurization 4 sections, tie handcart 102 is in the state of closing always, connect through tie line 103 between tie switch 101 and the

tie handcart

102, 6 kilovolt desulfurization 3 sections and 6 kilovolt desulfurization 4 sections between through tie line 103 interconnection intercommunication, service power between 3 units and 4 units is through tie line 103 realization interconnection.

The cabinet body of the interconnection switch 101 is divided into an upper part, a middle part and a lower part, and the control protection cabin 104, the switch cabin 105 and the grounding knife cabin 106 are sequentially arranged from top to bottom, a 6-kilovolt vacuum circuit breaker is arranged inside the switch cabin 105, and the 6-kilovolt vacuum circuit breaker is used for connecting and disconnecting the interconnection line 103. The control protection cabin 104 is internally provided with a control loop and a protection loop, the control loop is used for receiving an instruction on-off switch of an operator, the protection loop is composed of a protection device 114, a current transformer and a voltage transformer, the protection device 114 trips off the switch when the current transformer and the voltage transformer detect a circuit fault so as to prevent equipment from being damaged, the outer side of the control protection cabin 104 is provided with a live indicator lamp 107 and an operation button indicator lamp 108, a temperature and humidity controller 109 is arranged in the control protection cabin 104, and the temperature and humidity controller 109 is electrically connected with the control loop and the protection loop respectively. The grounding knife switch 106 is internally provided with a three-phase strong current circuit grounding knife switch, the grounding knife switch is pulled open when the No. 3 machine set and the No. 4 machine set work normally, and the grounding knife switch is closed after the electricity is proved when the No. 02 starting transformer is overhauled, so as to ground the strong current circuit. Switch in-out cabin operation holes 110 and grounding knife operation holes 111 are respectively arranged on the switch cabin 105 and the grounding knife cabin 106, a switch observation window 112 is arranged on the switch cabin 105, and a grounding knife observation window 113 is arranged on the grounding knife cabin 106.

According to on-the-spot actual conditions, the utility model discloses increase 6 kilovolts of units of 3, 4 section interconnection passageways for factory. The strong current circuit part is shown in figure 2, and the increased strong current circuit part is arranged in the cloud line. The 6 KV desulfuration 3-stage and 6 KV desulfuration 4-stage are arranged in a 6 KV desulfuration wire-transfer chamber. The spare positions and the spare switches on the two wire buses can be interconnected through the connecting lines, and the spare switches on the two wire buses are provided, so that the interconnection can be realized only by adding one connecting line. As shown in fig. 4, a spare switch is selected on each of the original two 6 kv desulfurization sections (6 kv desulfurization 3 section and 6 kv desulfurization 4 section), a three-phase common box conductor is added behind the switch cabin to be interconnected, the interconnected 6 kv desulfurization 3 section switch is named as 6T3T4, and the interconnected 6 kv desulfurization 4 section switch is named as 6T4T3 (in a normally closed state, serving as an isolation trolley). When the 6T4T3 is switched on at the working position and the 6T3T4 is also switched on at the working position, the two desulfurization buses can be interconnected, and service power between units can be interconnected and operated. The 6 KV desulfurization 3/4 section communication switch 6T3T4 cabinet layout is shown in figure 5. The cabinet body is divided into an upper part, a middle part and a lower part, and the cabinet body is respectively provided with a control protection cabin, a switch cabin and a grounding knife cabin from top to bottom. And a 6-kilovolt vacuum circuit breaker (switch) is arranged in the switch cabin and is responsible for connecting and disconnecting a high-voltage strong-current loop to realize interconnection of two electric buses. A control loop and a protection loop are arranged in the control protection cabin, and the control loop is responsible for receiving an instruction on-off switch of an operator; the protection circuit consists of a comprehensive protection device and current and voltage transformers and is responsible for tripping off a switch by the protection device when a circuit fails so as to prevent equipment from being damaged. A three-phase strong current circuit grounding switch blade is arranged in the grounding switch blade cabin, and the grounding switch blade is pulled open when the grounding switch blade normally works; when the equipment needs to be overhauled, the grounding knife switch is closed after no electricity needs to be checked, the strong current circuit is grounded, and the safety of maintainers is guaranteed.

Taking the working conditions that No. 3 machine set runs and No. 4 machine set needs to start a power supply during the process of No. 02 starting and overhauling as an example, the No. 3 machine set carries 6 KV 3A section by 6 KV, 6 KV 3 section carries 6 KV 4 section by 6 KV desulfuration through a newly added connecting line, and 6 KV 4 section carries 6 KV 4A section and 6 KV 4B section by the original two power lines. The 4 th unit can be started.

The utility model discloses a power capacity: the original 6 KV desulfuration 3 section, 6 KV desulfuration 4 section and two power lines thereof can be designed to run with a booster fan (the original rated current of the power inlet wire is 1123A) at the beginning, the later unit is transformed into 'leading and increasing in one', the booster fan is cancelled from the 6 KV desulfuration 3 section and 6 KV desulfuration 4 section, and other loads of the desulfuration 3 section and 4 section are increased a little, so the capacities of a wire bus and the power lines meet the starting requirement of the unit. In the actual supply reversing process, the 3 # unit can properly transfer the factory load, and the 4 # unit can select a single-side auxiliary engine starting mode. According to the high variable load data (the single-side current does not exceed 900A) of a factory during the starting of the unit at all times, the power supply capacity completely meets the single-side starting requirement of the unit. In addition, the rated current 2886A of the high-voltage side and the low-voltage side of the No. 3(4) plant can meet the requirements of the load of an operating unit and the on-line starting.

The utility model discloses a secondary circuit design: the system is designed into a scheme that 3 and 4 machine sets and 6 kilovolt service sections supply each other during a 02 # starting transformer overhaul period. Therefore, only the condition that the service power of one machine set is normal and the service power of the other machine set is lost is considered in the condition that the interconnection line realizes mutual supply. The logic is shown in figure 3.

(1) Allowable conditions for pushing 6T4T3 of 6 KV desulfurized 3/4 section contact handcart 6T4T3 from an isolation/test position to an operating position (the following conditions are all met): 1) the two-way power supply incoming line switches of the 6 KV desulfurization 3-section (the 6 KV desulfurization 3-section power supply A powered switch 6T33A and the 6 KV desulfurization 3-section power supply B powered switch 6T33B) are all switched off or the two-way power supply incoming line switches of the 6 KV desulfurization 4-section (the 6 KV desulfurization 4-section power supply A powered switch 6T44A and the 6 KV desulfurization 4-section power supply B powered switch 6T44B) are all switched off. 2) The 6 kv desulphation 3/4 section tie switch 6T3T4 was in the isolation/test position. 3) The 6 kv desulphation 3/4 section tie switch 6T3T4 is in the open state.

(2) Allowable conditions for pushing the 6 kv desulfation 3/4 section tie switch 6T3T4 from the isolation/test position to the working position (the following conditions are all satisfied): 1) the two-way power supply incoming line switches of the 6 KV desulfurization 3-section (the 6 KV desulfurization 3-section power supply A powered switch 6T33A and the 6 KV desulfurization 3-section power supply B powered switch 6T33B) are all switched off or the two-way power supply incoming line switches of the 6 KV desulfurization 4-section (the 6 KV desulfurization 4-section power supply A powered switch 6T44A and the 6 KV desulfurization 4-section power supply B powered switch 6T44B) are all switched off. 2) The 6 KV desulfurization 3/4 section is communicated with the handcart 6T4T3 to be in the working position. 3) The 6 kv desulphation 3/4 section tie switch 6T3T4 is in the open state.

(3) The allowable condition for closing the 6T3T4 communication switch at the section of 6 kilovolt desulfurization 3/4 (the following conditions are all met): 1) the 6 KV desulfurization 3/4 section is communicated with the handcart 6T4T3 to be in the working position. 2) The two-way power supply incoming line switches of the 6 KV desulfurization 3-section (the 6 KV desulfurization 3-section power supply A powered switch 6T33A and the 6 KV desulfurization 3-section power supply B powered switch 6T33B) are all switched off or the two-way power supply incoming line switches of the 6 KV desulfurization 4-section (the 6 KV desulfurization 4-section power supply A powered switch 6T44A and the 6 KV desulfurization 4-section power supply B powered switch 6T44B) are all switched off. 3) The voltage of the 6 kv desulfurization 3-stage is normal and the voltage of the 6 kv desulfurization 4-stage is 0 or the voltage of the 6 kv desulfurization 4-stage is normal and the voltage of the 6 kv desulfurization 3-stage is 0. 4) The 6 kv desulphation 3/4 stage tie switch 6T3T4 is in the service position or isolation/test position.

Thermal power factory electricity interconnection system use the back, utilize the stand-by switch position on the 6 kilovolts of desulfurization section of 3, 4 # units, at 6 kilovolts of desulfurization 3, newly-increased one section cross-over connection line between 4 sections of wire-buses, thereby solved 3, 4 # units start to become in 02 in case the tripping operation safety shut down risk is big and do not have the problem that the house service power started during maintenance, make 02 number start to become maintenance work and can develop by the courage, finally make 3, 4 # units house electricity reliability and flexibility obtain very big promotion.

The present invention is not limited by the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be equivalent replacement modes, and are all included in the protection scope of the present invention.

Claims

1. The utility model provides a thermal power factory electricity interconnection system, includes No. 3 unit and No. 4 unit, the required factory power of No. 3 unit operation is supplied by 3 factory hypervariates and the public transformer of No. 3 high pressures, the required factory power of No. 4 unit operation is supplied by 4 factory hypervariates and the public transformer of No. 4 high pressures, the starting source, the accident stand-by power of No. 3 unit, No. 4 unit all come from No. 02 starting transformer, No. 3 unit is connected to 6 kilovolts of desulfurization 3 sections respectively through 6 kilovolts of 3A section, 6 kilovolts of 3B section, No. 4 unit is connected to 6 kilovolts of desulfurization 4 sections respectively through 6 kilovolts of 4A section, 6 kilovolts of 4B section, its characterized in that: 6 3 sections of kilovolt desulfurization, 6 4 sections of kilovolt desulfurization arrange at 6 kilovolt desulfurization electric wire unions indoor, be connected with a tie switch (101) on 6 kilovolt desulfurization 3 sections, be connected with a tie handcart (102) on 6 kilovolt desulfurization 4 sections, tie handcart (102) are in the state of closing always, be connected through tie line (103) between tie switch (101) and tie handcart (102), through tie line (103) interconnection intercommunication between 6 kilovolt desulfurization 3 sections and 6 kilovolt desulfurization 4 sections, the house service is passed through tie line (103) and is realized the interconnection between No. 3 units and No. 4 units.

2. The electrical interconnecting system of claim 1, wherein: the No. 02 starting transformer is respectively connected to the 3 sections of 6 kV coal conveying and the 4 sections of 6 kV coal conveying through the 3 sections and the 4 sections of 6 kV public, the 3 # high-voltage public transformer of the No. 3 unit is connected to the 3 sections of 6 kV public through a power line, and the 4 # high-voltage public transformer of the No. 4 unit is connected to the 4 sections of 6 kV public through the power line.

3. The electrical interconnecting system of claim 1, wherein: the cabinet body of interconnection switch (101) divide into about three parts, and from top to bottom is control protection cabin (104), switch cabin (105), ground connection sword cabin (106) in proper order, switch cabin (105) inside is provided with 6 kilovolts of vacuum circuit breaker, 6 kilovolts of vacuum circuit breaker is used for putting through and breaking off interconnection line (103).

4. The electrical interconnecting system of claim 3, wherein: the control protection cabin (104) is internally provided with a control loop and a protection loop, the control loop is used for receiving an instruction on-off switch of an operator, the protection loop is composed of a protection device (114), a current transformer and a voltage transformer, and the protection device (114) trips off the switch to prevent equipment from being damaged when the current transformer and the voltage transformer detect circuit faults.

5. The electrical interconnecting system of claim 4, wherein: the control protection cabin (104) outside is provided with electrified pilot lamp (107) and operation button pilot lamp (108), be provided with temperature and humidity controller (109) in control protection cabin (104), temperature and humidity controller (109) electricity connection control circuit, protection circuit respectively.

6. The electrical interconnecting system of claim 3, wherein: the grounding knife switch is characterized in that a three-phase strong current circuit grounding knife switch is arranged inside the grounding knife cabin (106), the grounding knife switch is pulled open when the No. 3 machine set and the No. 4 machine set work normally, and the grounding knife switch is closed after no electricity is detected when the No. 02 starting transformer is overhauled, so that the strong current circuit is grounded.

7. The electrical interconnecting system of claim 3, wherein: switch business turn over cabin handle hole (110), earthing knife handle hole (111) have been seted up respectively on switch cabin (105), earthing knife cabin (106), switch cabin (105) facial make-up is equipped with switch observation window (112), earthing knife cabin (106) facial make-up is equipped with earthing knife observation window (113).