扬州市杰德电气设备有限公司主要经营开发的产品有:母线槽,滑线,电加热器,尼龙制品绝缘材料等,欢迎您的光临!

联系我们 Contact us
座机:0514-88777798
手机:13952561008
地址:江苏省扬州市宝应县柳堡镇工业区
公司新闻
您所在的位置:新闻中心 > 公司新闻 > 首页
母线槽位于不使用电压验证的一侧
更新时间:2021-03-09 08:29:00

Answer: (1) spare bus charging, when there is bus circuit breaker, bus tie circuit breaker should be used to charge bus. The charging protection of bus tie circuit breaker shall be put into operation, and the protection setting time shall be adjusted to zero when necessary. In this way, if there is a fault in the standby bus, the bus tie circuit breaker can be cut off to prevent the expansion of the accident.
(2) in the bus switching operation, the operating power supply of bus tie circuit breaker should be opened to prevent bus tie circuit breaker from tripping by mistake, resulting in the accident of pulling the disconnector with load.
(3) when all components of a bus have to be switched to another bus, generally, the disconnector of one component is connected to one bus, and then the disconnector of the other bus is disconnected. The other is to connect all the components that need to reverse the bus to the operating bus, and then disconnect all the corresponding disconnectors on the other bus side. Which method to use depends on the arrangement of operating mechanism and regulations.
(4) when the equipment is switched to another bus or the voltage transformer on the bus is cut off and the voltage circuit of the relay protection and automatic device needs to be switched to another voltage transformer for power supply, attention should be paid not to make the relay protection and automatic device misoperate due to the loss of voltage. Avoid the bad contact of the voltage circuit and the secondary charging of the neutral bus through the voltage transformer, which will cause the fuse of the voltage circuit to fuse and cause the misoperation of the relay protection.
(5) pay attention to the influence on bus differential protection during bus switching operation, and make corresponding changes according to bus differential protection regulations. Bus differential protection shall be put into operation in case of no special circumstances during bus switching operation.
(6) when the empty bus with inductive voltage transformer is charged, in order to avoid the series resonance between the parallel capacitance between the contacts of the circuit breaker and the inductive reactance of the voltage transformer, disconnect the isolating switch of the voltage transformer or connect the appropriate resistance in parallel (Series) in the secondary circuit of the voltage transformer before the bus stops power transmission.
Before bus switching operation, accident prediction should be done to prevent the expansion of the accident due to abnormal operation, such as insulator fracture of disconnector.
A: the high frequency protection is composed of the protection panel installed on both sides of the protected line and the channel for transmitting high frequency signals. When any part goes wrong, it will not work properly. For phase difference high-frequency protection and directional high-frequency protection, when the opposite side signal cannot be sent, misoperation will occur in case of external fault. For remote tripping high-frequency protection, it will refuse to operate. In order to check the integrity of the channel, it is required to check the channel regularly and directionally every day. When problems are found in the inspection, they should be handled in time or exit the protection.
3. In the verification of synchronous and non voltage reclosing devices, why are synchronous and non voltage relays installed on both sides A: if one side is used for no voltage verification, the other side is used for synchronous verification. Then, when the circuit breaker of the bus bar on the side without voltage verification trips due to some reasons (such as accidental collision, protection maloperation, etc.) under normal operation, because the opposite side does not act, there is voltage on the line, so the reclosing can not be realized, which is a big defect. In order to solve this problem, the synchronous verification relay is usually put into operation at the same time on the non voltage side of the verification, and the contacts of the two work together, so that the circuit breaker that tripped by mistake can be put into operation again. In order to ensure that the working conditions of circuit breakers on both sides are the same, the non voltage verification relay is also installed at the same side of the verification. After switching, it can be used according to the specific situation. However, it should be noted that when the non voltage verification relay and synchronous verification relay are put into operation on one side, the synchronous verification relay can only be put into operation on the other side. Otherwise, non synchronous reclosing will occur if both sides realize non voltage verification reclosing at the same time. Why can't the transformer differential protection replace the gas protection A: the gas protection can reflect any fault in the transformer oil tank, including overheating and burn of iron core, lowering of oil level, etc., but the differential protection has no response. For example, the transformer winding has a small number of turn to turn short circuit, although the short circuit current in the short circuit turn will cause serious overheating of local windings and produce strong impact of oil flowing to the conservator, the phase current is not large, so the differential protection does not respond, but the gas protection can react sensitively, which is the reason why the differential protection can not replace the gas protection.
A: (1) during oscillation, the voltage and current values at each point of the system oscillate to and fro, while during short circuit, the current and voltage values change abruptly. In addition, the change speed of current and voltage is slow in oscillation, but the sudden change of current and voltage is large in short circuit.
(2) the phase angle between the current and the voltage at any point of the system changes with the change of the power angle during oscillation, while the angle between the current and the voltage is constant during short circuit.
6. For gas protection of transformer in operation, when there is any work on site, the position of heavy gas protection should be changed from "trip" to "signal" Answer: (1) when filling and filtering oil; (2) when the respirator is unblocked or silica gel is replaced; (3) when opening the vent valve, oil drain valve and oil inlet valve in all places except the upper vent valve of oil production sample and gas relay; (4) when opening and closing the valve on the connecting pipe of gas relay; (5) when working on gas protection and its secondary circuit; (6) For the nitrogen filled transformer, when the conservator is vacuumized or nitrogen is supplemented, when the transformer is filled with oil, filtered, replaced with silica gel and treated with respirator, the heavy gas can be put into trip after one hour trial operation after the above work.
Answer: (1) the main protection is to meet the requirements of system stability and equipment safety, and can selectively cut off the protected equipment and line at a high speed.) the backup protection is to cut off the fault when the main protection or circuit breaker refuses to operate. Backup protection can be divided into remote backup and near backup.
1) remote backup protection is realized by the protection of adjacent power equipment or lines when the main protection or circuit breaker refuses to operate.
2) near backup is that when the main protection refuses to operate, the backup protection is realized by another set of protection of the power equipment or line; when the circuit breaker refuses to operate, the backup protection is realized by the circuit breaker failure protection.
(3) auxiliary protection is a simple protection added to supplement the performance of main protection and backup protection or when the main protection and backup protection are out of operation.
Answer: all transformers in parallel operation have the same transformation ratio, short circuit voltage and wiring group. Different transformation ratio will produce balanced current between parallel operation transformers, which increases the loss of transformer and increases or decreases the load of transformer. When the short-circuit voltage is not equal, the transformer with small short-circuit is easy to overload, and the transformer capacity can not be used reasonably. The parallel operation of transformers with different wiring will burn the transformer due to the larger phase difference and larger equalizing current.
A: the fundamental cause of high-order harmonic generation is the waveform distortion caused by the nonlinearity of some equipment and loads in the power system, that is, the applied voltage is not linearly related to the generated current. For example, transformer, AC / DC converter and electric arc furnace transfer, transform and absorb the fundamental energy supplied by the generator of the system, at the same time, convert part of the fundamental energy into harmonic energy, and send a large number of high-order harmonics to the system, which distorts the sinusoidal waveform of the power system. At present, there are three main types of harmonic sources in power system: magnetic saturation type, electronic switch type and arc type. The influence of harmonic on power grid is: the main harm to rotating equipment and transformer is to cause additional loss and heat, and metal fatigue and mechanical damage due to long-time vibration; harmonic will cause additional loss of lines; harmonic will cause system resonance, protection device malfunction, damage system equipment, and endanger the safe operation of power system; harmonic will also interfere with communication equipment. The main measures to limit harmonics are: increasing the pulsation frequency of converter, installing AC filter and active power filter, and strengthening harmonic management.
10. When the system frequency is lower than 49.1 Hz or 49.0 Hz, how does the bus provincial dispatching regulate the frequency exception handling Answer: (1) when the frequency is lower than 49.1 Hz, the personnel on duty of each power plant and substation monitoring center (substation) should take the initiative to quickly switch the line with automatic low-frequency load shedding device that is active but not active to 49.0 Hz. When the line with automatic low-frequency load shedding device is active, the dispatchers on duty of each local dispatching center should take the initiative to switch it off according to the "accident switching sequence" to recover the frequency above 49.0 Hz; < br / > (3) in case of low frequency operation, the power can be transmitted only when the line tripping by switching and automatic low frequency load shedding device is above Hertz, and the approval of the dispatcher of the provincial dispatching shift is obtained (except for the one requiring security power supply). The provincial dispatching order to switch off the line route, and the provincial dispatching order to resume power transmission.
11. In order to deal with the accident quickly and prevent the accident from expanding, which situations can be handled by the accident unit without waiting for dispatching instructions? < br / > Answer: (1) when there is a threat to the personal and equipment safety, take measures according to the site regulations; (2) when the plant and station power is completely or partially stopped, restore the power transmission; (3) when the voltage transformer fuse is blown or the secondary switch trips, stop the relevant protection; (4) isolate the damaged equipment; (5) when there is voltage on both sides of the switch after the power contact line trips, restore the synchronous parallel or parallel loop; (5) Automatic safety devices (such as machine cut-off, load cut-off, low-frequency splitting, low-voltage splitting, etc.) shall be replaced manually when they are not activated; (6) this regulation and site regulations clearly stipulate that they can be handled by themselves without waiting for the instructions of the dispatcher on duty. The above operation shall be reported to the dispatcher on duty as soon as possible.
Answer: (1) when the bus voltage of the power plant disappears, the on-site personnel on duty should first disconnect the switches that may call, and then disconnect all switches (if there is power supply for the double bus, the bus tie switch should be disconnected first). On the one hand, the affected auxiliary power should be quickly restored, and on the other hand, the bus should check the bus, and report to the on duty dispatcher.
(2) when the bus voltage of the substation with two or more power supplies disappears, the on-site personnel on duty shall reserve a power line switch on each bus, disconnect other switches (if there is power supply on both buses, the bus coupler switch shall be disconnected first), check the bus and report to the dispatcher on duty.
(3) when the bus voltage of the substation equipped with the automatic switching device of the standby power supply disappears and the automatic switching device of the standby power supply refuses to operate, the on-site personnel on duty need not wait for the dispatching instruction to immediately open the power supply line switch and close the standby power supply switch. If the bus still has no voltage, immediately open the standby power supply switch and then open other switches. Check the bus and report to the dispatcher on duty.
(4) when the bus voltage disappears, if obvious fault is found in the bus, all switches and knife switches of the bus shall be disconnected and another bus shall be used for power transmission. When switching bus operation, it should first open the fault bus side switch, and then close the non fault bus side switch.
If there is no obvious fault in the bus, the bus differential protection of the generator can be used to trip. If the bus voltage disappears due to the fault symbol, it should not be sent before the cause is found out.
(6) bus
  以上内容来自封闭母线厂家杰德电气,转载请注明。