热电厂循环水泵高压变频调速控制系统研究和实现

STUDY AND IMPLEMENTATION OF HIGH-VOLTAGE VARIABLE-FREQUENCY SPEED ADJUSTABLE CONTROL SYSTEM OF CYCLE WATER PUMP SYSTEM IN THERMAL POWER PLANT

循环水系统是火力发电厂的“血液”,其性能直接影响发电机组的出力。文中设计并研制了茂名热电厂 4号机组的循环水泵高压变频调速监视控制系统。系统控制器由可编程控制器 ( PLC)和工业控制计算机 ( IPC)组成。 PLC控制系统选择双机热备用结构 ,实现系统的所有逻辑控制功能 ;IPC系统使用组态软件来实现系统的监视、保护等管理功能。PLC系统和 IPC系统组成 MB+网络 ,实现对整个系统的监视和控制。控制系统以汽机的“最优真空”为控制目标 。

The cycle water pump system is the “blood system” of Thermal Power Plant, which influences the contribution of generator directly. In this paper, research and accomplishment of high voltage variable frequency speed adjustable control system of cycle water pump system of the No. 4 generator in Maoming Thermal Power Plant was carried out. The main controller is composed of programmable logical controller (PLC) and industrial personal computer (IPC) in MB + network. PLC system is adopted in hot standby mode, which fulfills all logical program of the system. IPC system is adopted with configuration software to realize monitoring and management functions. “Optimal vacuum of turbine” strategy is adopted to control the variable frequency inverter of the cycle water pump, and the problem of hot water's always overflowing from the hot pool to the cool pool is resolved at the same time.