LDZ-D Simulation Test Device For Circulating Cooling Water Dynamic Control System Design

In the development of industry, recycled water can improve productivity, reduce operating costs, save water resources, protect the environment, improve the comprehensive benefit,etc. Using conventional instrumentation dosing control is the traditional method, this method is difficult and the control accuracy is not high enough. Therefore, according to the Shandong Electric Power Research Institute for the control of circulating cooling water requirements, the LDZ-D type of circulating cooling water simulated dynamic test equipment is designed, and has been put into use in February 2015. This device is a special test equipment for water treatment, and it can combine running condition, comprehensively test and evaluate the ability of water stabilizer formula, which is the corrosion and scale inhibition performance.This device uses the SHCAN2000 field bus control system based on CAN bus and FIX configuration software, realizes the function of automatic dosing. By controlling the frequency converter to control the fan and circulating water pump make the method to controlling the temperature and the circulating water flow more simple, and greatly improve the precision of the system, reduce the difficult.In this paper, the whole design and implementation process of the LDZ-D type of circulating cooling water simulated dynamic test equipment for water treatment are clearly described. The whole system has the function of management and monitoring, lower computer control system implement the cascade PID control of the inlet temperature and steam temperature, and the single loop PID control of the circulating flow, and implement the control of pumps, valves in in the device. Upper machine is composed of a commercial computer, responsible for monitoring the running state for experiment device, and to generate reports and experimental data of the curve. “The centralized management and decentralized control” is the main characteristic of this control system.Features of this design are: using FIX monitoring software makes the whole production operation’s process visualized; Given FIX rapid response to production events, can reduce the consumption of raw material, and improve the productivity and production efficiency; Lower computer using low cost intelligent module developed by ourselves, to implement the acquisition of real-time data and the function of automatic control, and the cost can be reduced. The system is safe, reliable, fully functional, easy to operate and high cost performance.