Research On The Upgrading Plan Of YunFu C Power Plant Auxiliary Power System

More and more house-service equipment is used in power plants.Auxiliary power systems are also becoming more complex.Reliability and rationality of the Design of Auxiliary Power system is an important basis for the safe Operation of Generator sets and even Power Grid.The key to ensure the safe operation of auxiliary power system is to eliminate its potential deficiencies and hidden dangers.The start standby power supply of the circulating fluidized bed thermal power plant with partial generation and transformer connection mode is connected with the same busbar of the system from the high voltage side for the safety consideration of the switching of the auxiliary power system.Taking Yunfu C Power Plant as the research object,this paper studies the hidden trouble existing in the auxiliary power system of this type of power plant and the corresponding retrofit scheme.Based on the actual situation of Yunfu C Power Plant,this paper puts forward two retrofit schemes: "build a new Yunfu A ~ Yunfu C plant line" and "build a new 110 kV standby power supply".The technical feasibility of the two schemes and the scheme of accessing the system are analyzed.Then the economy of the two schemes is compared and the latter is selected as the optimal scheme.And the analysis and design of the electrical primary system and the secondary system of the selected scheme are carried out.Based on the analysis of plant load and two different power supply methods,the capacity of 110 kV standby transformer is selected.The main parameters of electrical equipment in the scheme are determined and checked by the method of electrical calculation.On this basis,after considering the main risks of switching between power supply and 110 kV backup power supply,the control principle and the need to switch power supply,the start-up condition and logic function of the quick cut device of 110 kV standby power supply are determined.And the operation scheme of "cold standby" for 110 kV standby power supply Configured inrush current suppression device is determined by the method of scheme comparison and selection.In this paper,the simulation model of the scheme is built with PSCAD/EMTDC software,and the simulation results of the operation of the backup power supply are analyzed,and the feasibility of the scheme is verified.At last,through the analysis of the test results and data after the implementation of the scheme,the feasibility and effect of the reconstruction scheme are verified.It shows that the reconstruction scheme can make up for the existing deficiencies of the auxiliary power system of Yunfu C Power Plant.It also provides a reference for the design of the new or extended auxiliary power system in the same type of power plant.