Characteristics and Application of Inner Mongolia Power Technology HEC3 Type Circuit Breaker Zhang Yaopu, Liu Xinjun (Huanghe Wanjiazhai Water Conservancy Hub Co., Ltd., Shanxi Bijia 036412) Wanjiazhai Hydropower Station installed 6 sets of single-machine capacity 180MW Francis turbine generator sets, generators and transformers The unit wiring is formed. The generator outlets of Units 1, 3 and 5 are selected from the HEB. type circuit breaker of ABB Company of Switzerland and lead to the factory branch. The structural performance and installation operation of the circuit breaker are introduced and analyzed.
HEC. Circuit breaker; structural features; installation and operation of TM568 Wanjiazhai Water Control Project is a dam-type hydropower station, installing 6 vertical-shaft mixed-flow hydroelectric generating units with a single unit capacity of 180MW, with a total installed capacity of 1080MW. The generator voltage is 15.75kV. The phase-sealing mother is the unit wiring, and the high-voltage side GIS is connected to Jinmeng Power Grid with 220kV6 return line respectively. The designed annual average power generation is 27.5X108kWh. By the end of 2000, the 1, 4, and 6 machines are responsible for the network-to-network power flow adjustment in Jinwang. 2, the machine in the Mongolian network to undertake the task of peaking. After all the units are put into production, each of the two provinces and districts has three units operating. The outlets of No. 1, No. 3 and No. 5 with the branch of the factory are selected by the HEC. type circuit breaker of ABB of Switzerland, and the disconnection of the generators of No. 2, No. 4 and No. 6 are only equipped with the isolating switch. Since the circuit breaker has been put into operation, its operation is in good condition. The following is a brief description of its main parameters, structural performance, installation and operation.
Parameter value rated voltage / kV maximum operating voltage / kV power-frequency withstand voltage between ground and circuit breaker break / kV impact tostand voltage between ground and open circuit breaker rated voltage recovery rate / kV! S-1 20C normal inflation pressure / kPa closing time (to main contact contact) / ms opening time (to main contact separation) / ms breaking time (to arc extinguishing) / ms 1 electrical main wiring and HEC. The main parameters of the circuit breaker are the main electrical wiring. The main parameters of the HEC. type circuit breaker are shown in Table 1. HEC. Type circuit breaker, isolating switch, maintenance grounding switch and secondary circuit. The factory test is based on S111EEEC37.013EC and Relevant standards are carried out.
2HEC. Type circuit breaker structure and characteristics 2.1 The structure consists of three single-phase closed casing SF6 circuit breakers composed of three-phase system welded to the phase-sealing mother, together with the operating system and control equipment are all installed on a common basis. The circuit breaker, the isolating switch, and the grounding switch are all installed in the same housing. The actuator is installed in the lower part of the circuit breaker complete equipment cabinet, located in the axial direction of the circuit breaker, and operates the three-phase circuit breaker via a common operating lever. The position indicator shows the split state of the operating device in situ and sends the position signal to the monitoring system.
2.2 Body structure characteristics HEC. Type circuit breaker body structure (opening state) consists of operating lever, main contact (moving), arcing contact (moving), arcing contact (static), main contact (static), body housing And other components. The gap between the fractures is 60mm, using SF6 gas as the arc extinguishing and internal insulation medium, the charged part is insulated by air to the ground, and the operation work is significantly reduced by the integrated air blowing principle and the arc heat effect. This self-energy principle can reliably break. Big editor: Liu Yuping short-circuit current, while ensuring that no overcurrent is generated when breaking a small current. Because the product adopts the auxiliary measures of arc rotation in the arc extinguishing chamber, the arc ablation of the arc contact is greatly reduced.
When the circuit breaker is closed, the arc contact (moving) first contacts the arc contact (static), and then the main contact (moving) of the load is inserted into the main contact (static). The order of the opening action is reversed, so that the arc contact current breaking and the load current are separated, which avoids the loss and ablation of the main contact, and ensures that the main contact still has a specified load carrying capacity after a large number of operations. .
2.3AHMA spring energy storage hydraulic mechanism AHMA spring energy storage hydraulic operating mechanism combines the advantages of spring mechanism and hydraulic mechanism. The spring is stored by a hydraulic mechanism. The maximum working pressure of the oil pump is 60 MPa. The mechanism has the characteristics of simple, hydraulic system without pipe connection, compact, low noise, high reliability, and not affected by temperature changes. It is the schematic diagram of the AHMA hydraulic operating mechanism (opening position). When the brake is opened, the side of the working piston 3 with the operating rod is the normal charging pressure. The side of the working piston top is connected with the oil storage tank, and the pressure is reliable at one end. Keeping in the open state; when the closing electromagnetic pilot valve 10 is actuated, the main valve is switched to connect the high pressure cylinder to the top end of the working piston, and the working piston is connected to the high pressure system at both ends; since the working piston top side area is larger than the working The piston has an area on the side of the operating rod, and the piston is moved to the closing position based on the "differential pressure" principle. 1 a circuit breaker working cylinder working piston 4 with pressure reading energy storage cylinder energy storage piston energy storage spring oil pump 9 a gate electromagnetic pilot valve 1 - closing electromagnetic pilot valve M motor AHMA type hydraulic mechanism operating principle energy storage spring 7 according to operation The required amount of oil releases the tension. These oil quantities are immediately replenished by the hydraulic pump. The general pump pressure is not more than 2 minutes. A check valve is installed between the hydraulic pump and the high pressure accumulator cylinder to prevent the pressure from falling when the pump is stopped. The operating speeds of closing and opening can be adjusted by separate throttle bars.
2.4 Isolation switch, grounding switch and capacitor switch The complete set of equipment is provided with a set of isolating switch in series with the circuit breaker and two sets of grounding switch and two capacitors (see). The series isolating switch is installed on the outlet side of the circuit breaker and is in the same casing. It is a tubular telescopic unit, the moving contact is located on the transformer side, and the static contact is located on the circuit breaker side. The grounding switch has its hinged moving contact grounded, and the static contact is connected to the charging side. The isolating switch and the grounding switch can be opened and closed by electric or manual operation, and have an electric interlock device to avoid misoperation. Because there is no mechanical interlock, it should be operated electrically under normal conditions. The protective capacitor is mounted outside the switch housing and only the porcelain sleeve extends into the housing.
The transformer side capacity is 0.26! F, generator side capacity is 0.13! F. 3 Installation and operation conditions After the equipment arrives at the installation site, it is checked and accepted according to the supply list. Except for the case where the circuit breaker of the No. 1 machine is slightly loosened by the end of the generator side protection capacitor, the coupling screw is loose. No other components are found. abnormal situation.
The circuit breaker was installed under the direction of ABB's field service personnel. The whole lifting is in place, the primary line is connected, the switch equipment shell and the sealing shell are welded, and the control cable is connected, and the routine project inspection and the secondary circuit action test are carried out according to relevant standards. Except for the isolation switch of the No. 1 machine isolating switch, the insulation rod is twisted and replaced when it is closed due to damage, and the rest meet the standard requirements.
The generator outlet circuit breaker of No.1 generator was connected to the grid from 1998-11-28 to 2000-12. It operated a total of 11 923h on the power grid and operated 185 times in a combined operation (the unit was opened for 5 times due to the faulty operation of the automation components). The hydraulic pump was pressed 360 times and all of them were running normally. During this period, the closing coil was burned out and replaced with spare parts. The machine outlet circuit breaker was put into operation on the Internet since the end of 1999 to the end of 2000. 4 2717 points 177 times did not appear. Abnormal; the No. 5 machine outlet circuit breaker 2000-12 was put into operation on the grid.
4 Conclusion Wanjiazhai Water Conservancy Project will be completed and accepted before the end of 2001. Because the unit is responsible for the adjustment of the network between Jinwang and the peaking task in Mengwang, the number of starts and stops is high, and the number of corresponding circuit breaker operations is high. To ensure the normal operation of the circuit breaker, it is necessary to regularly check the SF' gas pressure during operation, and observe whether the operation frequency and operation sound of the pressure oil pump are normal. If the number of pressure times is frequent, the oil leakage phenomenon in the pressure storage cylinder is indicated; the position indicator indicates that Preventive tests and secondary loop tests are performed correctly and in accordance with the relevant regulations.
According to the relationship between the load current and the number of operations of the HEC3 type circuit breaker provided by the manufacturer, combined with the unit parameters of the Wanjiazhai Hydropower Plant, the number of combined operation of the circuit breaker should be more than 10,000 times. The current sharing operation under the rated power of the cut-off generator should also be more than 1000 times. The overhaul period of the circuit breaker components shall be not less than 15a. Whether the above requirements can be met, it is also required to be tested in the actual operation in the future.
(Finish)
Interactive tables and chairs for children provide fun and safety for children of all ages and sizes. The desk features an adjustable tilt surface from 0 to 40 degrees, and an organized pull-out drawer for paper, coloring books, coloring utensils, and more. This set is ergonomically designed to provide comfortable sitting and correct body posture, which are important for good body posture and health, even from an early age. This table and chair table is recommended for ages 3-14. Initial tabletop setup takes only a short time, and it's easy to move after assembly.
Kids Ergonomic Chair,Single Piece Study Chair,Moveable Study Chair,Orthopedic Study Chair
Igrow Technology Co.,LTD , https://www.aigrowdesks.com