S7-300PLC的电加热温度控制系统设计

针对电加热系统易出现的温度波动性大、控制精度差、超调严重等问题,根据电加热系统中温度控制的特点和要求,采用了由西门子S7-300PLC、三相可控硅调功器等组成的高精度温度控制系统.介绍了该系统的硬件配置和软件设计,并运用PID(比例、积分、微分)控制算法,达到减少系统波动性,解决超调量过大,提高控制精度等目的.实现监控整个电加热系统的加热过程,使得系统的最终温度符合设计目标值,并且能够保持在设计温度范围内,为以后进行实际试验积累经验和提供技术支持.

An electric heating system design of temperature-control based on S7-300PLC

In view of the problems of electric heating systems: temperature fluctuations,lower control precision,serious overshoot,etc.and based on the characteristics and requirements of temperature control in electric heating systems,a high-precision temperature control system which consisted of a three-phase silicon controlled rectifier and Siemens S7-300PLC was designed.It introduces the hardware configuration and the software designing of the system.Through the PID control algorithm it could achieve the goal of reducing its volatility,solving the overshoot problem and improving the control precision.The monitoring of the heating process of the whole system can be realized.The electric heating system’s final temperature can meet the design target and keep it in the range of design temperatures.it accumulates experience and provides technical support for actual experiments in the future.