| The fast response and frequency modulation is required in the modern electric power field.With the detailed rules for two evaluation criteria in recent years,all of these factors raise higher and higher requirements to the automatic control level of unitCoordinated control system is the main way of unit control.To set up and optimize the coordinated control system continuously is the key to guarantee the economic operation of the coal-fired power plant, and improve economic efficiency of unit load frequency control ability.This article researchs the current situation of 250MW No.4 unit in DouHe power plant,and carries on the optimization design of coordinated control system.First of all,the thermal characteristics of No.4 unit are analyzed deeply and the controlled object model is built; Secondly,considering the present situation of No.4 unit,such as the update of heating surface, the desulfurization and denitration in recent years,the main factors which affect the control effect are analyzed.The third, the article builds a direct energy balance control system with direct power control strategy, designs and optimizes the boiler master control circuit, turbine master control circuit with relevant tests;designs the main steam pressure setting system with the function to generate the main steam pressure set point under different working conditions and sliding pressure of the undisturbed switching function,combining with the actual load characteristics of No.4 unit;increases the design of the function of RB in the original control system,considering the scene auxiliary engine running status in recent years and the detail questions such as the actual equipment control accuracy, equipment capacity and margins,air volume control logic.This design has been proved to be effective and feasible with the test and the actual operation.Finally, the article summarizes the design and optimization work,and points out the certain popularization value in the 300MW grade unit. |
PDF Full Text Request