"机械厂车间低压配电及变电所设计方案"

ystems and the power supply system of the workshop substation. This paper first carries out load calculation, and according to the power factor requirements, reactive power compensation is carried out on the low-voltage busbar side, and then the capacity and number of main transformers are determined. The main busbar scheme is determined from the perspective of economy and reliability. Secondly, the maximum and minimum short-circuit currents under the maximum and minimum operating modes are calculated through short-circuit current calculation, and the wire type and various electrical equipment are determined. Finally, according to the factory's requirements for relay protection, relevant protection schemes and secondary loop schemes are determined. This design adopts the coefficient method for load calculation, and the reactive power compensation adopts the low-voltage side capacitor parallel compensation method, which can compensate the previous reactive power on the low-voltage side with better economic benefits. According to the electrical characteristics and requirements of the mechanical processing workshop, the main busbar scheme adopts the main busbar scheme with no busbar on the high-voltage side and segmented single busbar on the low-voltage side. Based on the comparison of economic and installation conditions between dry-type transformers and oil-immersed transformers, two sets of SC9-500/10 series dry-type transformers are selected. After carefully studying the actual data of each load and strictly following the national regulations, the power supply system design scheme is designed according to the above design steps in order to achieve the purpose of improving production efficiency. Keywords: low voltage distribution system; load calculation; main busbar; substation; short-circuit calculation.