工厂供电系统外文翻译

附录四英文文献及译文Analysis of the reasons for the low power factor of the factory power supply system, and to improve power factor and to take effective idle work compensation measure is discussed. To saved the electrical energy, raised enterpriseps economic efficiency has important effect。

Large and medium-sized enterprises PeiDianJian with responsibility for the whole enterprise management and distribution of electricity. At present, most of the enterprise management mode PeiDianJian obsolete, low automatization, difficult to adapt to the requirements of the development of enterprises. In view of this situation, we have developed PeiDianJian monitoring and management system. This system in the computer as the core, real-time monitoring of electric parameters, PeiDianJian all the data processing, dynamic display of statements and output. This system can be used in the PeiDianJian enterprise technical renewal and the transformation of enterprise to do well planned, save electricity, improve economic benefit has important significance.We use the mains by huge power supply system is provided, all the network supply circuit is only for each of the power supply system, network, a tiny branches output. Metal wires connected by good conductors of power supply circuit, each of its source power substation, and then from that power to client to substation and its level in scale, thousands of kilometers and hundreds of kilometers of kilometers. Bare wire in the air in the vertical distribution of atmospheric mountain while high and low, in accordance with the Qing, from dozens of rice to thousands of meters and hundreds of meters above all common. 2 km In such a large scope, the vertical distribution and wide for substation online, due to weather, no matter where or by direct discharge, clouds cloud in discharging, in the air and good conductors of bare wire easily inductive or direct lightning introduction to. This is the power system and power equipment to be struck by lightning external environment.Power supply system and electric defense methods of lightningAnalysis of the power supply system and electric easily be struck by lightning, can draw on electrical equipment, defense lightning damage, should be perfected in the power supply system, and avoid thunder lightning protection measures, the core problem is how to maximize effectively or truncate the high voltage and the thunder and lightning, strong flow under the frequency of more than 10 KHz seitching invasion.transformer segregation lawsTo effectively cut from the high voltage power and strong currents, currently use transformer isolation method. So-called isolation method, is based on transformer transformer equation:EM = 4144fNBMSType of EM for transformer original (vice), unit V; potential edge F for power source) frequency, unit (speed, N the original (vice) side of coil, The intensity of magnetic core materials BM, unit Wb/M2, S for the core area, unit M2.This equation, powerful lightning invade the transformer, due to transformer voltage electric ray than the normal supply of high pressure many times, make incentive magnetic induction than the maximum allowed by magnetic core transformer core strength BM, thus the magnetic saturation, transformer -- electricity failure, GaoLei voltage transform temporarily cannot transfer to the transformer, a deputy side of transformer protection lightning channel, the deputy of electrical equipment load. While there are usually installed transformer power valve can be powerful lightning and the lightning flow into the earth, and in the safe, high voltage, current, powerFlow, fuses will fuse off. Stop So, always packed transformer electrical equipment configuration of transformer, than by lightning bad probability is greatly reduced.Why in the fall after the power supply, sluice stop there will still be struck by lightning disasters. This happened because lightning, invading transformer connected by vice and load of electrical equipment based on low, still can exist, these induction lightning induction lightning electronics products will cause of lightning. This problem is often neglected, many lightning disasters, the event is not solved theproblem. The successful development of lightning power, for we solve this problem.Lightning arrester powerFor truncated or stop high-pressure seitching in metal wires to load caused by lightning, electric 1890 invented the clearance of the way after the lightning series fuse, 1922 made us Westinghouse carbonized silicon arresters. To use the 1972 Japan dielectric properties research into fell seconds with no gaps (ZnO) service. Current power supply system is widely used in such power lightning.Zno arrester by zinc oxide thermistors, each thermistors according to need to have it made in certain switching voltage (psa). When in the lower voltage arresters ends switching voltage (psa), high resistance thermistors present state, arrester doesn't work. When lightning arrester ends when, in the voltages above switching voltage (psa), thermistors, low resistance by breakdown, even close circuit state, in a very short time (50ns ´ s, 10-9) arrester is high, the work of a lightning through introducing the earth grounding safety. When, after the lightning arrester stabilised, voltage on both ends of the lower voltage switching voltage (psa), thermistors and present state of high value, lightning arrester stop working, electric conduction normal power.FenLiuXing avoid thunderFenLiuXing avoid thunder, is the core of wire cable in transmission series on two capacitor, input shunt capacitor in an inductance coil. So, when the capacitance and inductance coil capactance C L reasonable choice of inductance, make through two more than 10 frequency capacitor, much like KHz TV signal frequency speed to sign for dozens of hundreds of megabytes speed signals through the capacitance, and lightning frequency circuit reactance small majority in 100 KHz, when lightning through the capacitance, will produce larger pressure drop. And through the situation, high capacitance signals through the inductance greater pressure drop when L, much lower frequency of lightning, through the low impedance, large discharge by lightning, XieRu grounding. Television antenna lightning current share this line shunt principle and method.Production of equipment, such as mechanical processing machine, with various kinds of crane, with induction motor, etc, these large and electric power load isperceptual load, make the power factor of power supply system, the influence of distribution transformer lines and economic operation of power sector, reach the power factor, thus must adopt the reactive power compensation measures to improve the power factor, and can save energy and reduce consumption.The power factor of system of power supply is an important technical and economic indexes, the power factor of electric equipment is reflected the active power and the ratio of power nai. Relevant procedure: high voltage power supply power plant, the maximum load of power factor may not be less than 0.9, Other factories, power factor may not be less than 0.85.The main factors that affect the power factorThe power factor of ac electric equipment, mainly because in its working process, in addition to generate power loss, also produce reactive power loss. Therefore improving power factor the essence of the problem is to reduce the electric equipment of reactive power consumption. Asynchronous motor and power transformer is reactive power loss of the main equipment and power lines of reactive power loss, it is current through the lines. Circuit reactance.Parallel compensation in power capacitors supply system of factory installed position, have high concentrated compensation, low-pressure concentrated compensation and separate compensation on-spot three modes, etc.Theoretically speaking, the reactive power compensation is the best way of reactive power, where is produced, the whole system where compensation will not reactive current flow, but in actual power supply system in this is impossible. We currently have a 10 kv power supply system, and has three switch power transformer substation, three workshops 800kV A respectively, 560kV A capacity, 630kV A. Dynamic load hundreds of machine tools and machining, electric welding machine, etc. Combined with practical, electricity load during load fluctuation change is big, the characteristics of small load after midnight, in order to avoid over compensation, and meet after midnight on all load cases are adopted to improve the low voltage offset, automatic reactive compensation devices.分析了工厂供电系统功率因数偏低的原因,探讨了提高功率因数的方法及采取的有效无功补偿措施,对节约电能,提高企业的经济效益有重要意义。