Research On The Key Technology And Design Of Power Supply System For Large-scale Coal Chemical Engineering

Primary energy is characterized by “rich in coal,poor in oil and short in gas” in China.Nowadays,with the shortage of oil resources and the governments' strongly support in developing the coal cleaning utilization technology,coal chemical industry gets more matured and perfect,and conversion efficiency of raw coal goes up continuously.As a result,coal technology achieves its cleanness,high-efficiency and high economical use.In order to cater for the market demand,the product structure has changed from the original single and low-ends products into diverse and high-end products.Therefore,the procedure of newly-established coal chemical industry becomes more complex and products are more diversified,followed by the expanded industry scale.However,since electricity energy is served as the major power source of this industry,the reliability and flexibility of power supply system exerts a decisive influence on the safety and continuous production of large coal chemical enterprises.In this paper,the power supply system design and crucial technology are mainly explored to meet the demand of large coal chemical project on power system.The power supply system of factory is an important part of electrical system,the central task of which is to supply and distribute the electric energy.Its design should not only satisfy various specific requirements needed in production process to ensure a safety and reliable energy supply,but also make the project reasonable with low investment and operation cost.By comparing and designing diverse commonly used main wiring scheme,this research designs power distribution scheme suitable for this large coal chemical project.First of all,start with load calculation—basis of the power supply design,according to the operation characteristic,load level and suitable method of load calculation,so as to lay a basis for the following research on site selection of main sub-station and main wiring scheme of the whole plant.Then,the power supply,voltage classes and main transformer capacity can be determined on the basis of calculation result.Finally,according to the load distribution feature and general layout requirement,it determines 110 kV main sub-station site selection for this project.Comparing with the widely used main wiring scheme and considering the electrical load and different power supply requirement for different voltage classes,the main wiring scheme of 110 k V and 35 kV is designed.By comparison with the starting mode of large power motor,it selects the qualified power supply scheme of large motor,and determined the specification of electric primary equipment through calculation.In regard to some important low-voltage motor,the restarting device controlling system is added to deal with “voltage fluctuationing”,and coupled with related equipment,it ensures a smooth operation of these important low-voltage motor.At last,the analysis on operation status shows that the reliability and economical efficiency of the power supply and distribution system has achieved expected purpose,and verifies the rationality of this power supply scheme for this project.