Development And Application Of AVC Integrated Control System For Thermal Power Unit

Voltage is an important standard to measure the quality of power quality.Effective control of voltage,not only can improve the power quality,but also can reduce the network loss of power system,and improve the economic performance of the system.Power plant is an important part of the grid,th e bus voltage control directly affects the voltage level of power grid,in order to improve the level of control of the bus voltage of the power plant,the country has carried out the power plant automatic voltage control system(AVC)construction.Through the research and analysis of the automatic voltage control(AVC)system,this paper presents a design scheme of AVC based on DCS.The scheme is characterized by power function extension of AVC in the existing DCS system,to make the logical configuration design and monitoring screen design of power plant AVC system by using DCS software,constitute a set of information and control integration platform.In this AVC system,we developed the IEC 60870-5-104 protocol master station to realize the communication of the AVC slave station and the dispatching AVC master station.At the same time,the heartbeat signal is added in this design to judge the communication status inside AVC system,to determine whether the plant can be put into the AVC function.In control strategy,the reactive power allocation algorithm is improved to common units,joined the unit reactive bias function,makes the plant personnel on duty can be manually set reactive intervention.In this design,we also joined the AVC assessment system,it can provide decision support for power plant personnel,timely correct mistakes and improve the efficiency of the assessment.After the AVC system is put into operation,Through the AVC test(static test and dynamic test),the safety test and function test of AVC sub-station are completed.The system has the advantages of novel design,cost saving,stable and reliable and powerful function.It can improve the power quality of regional power network,and has good popularization and application value.