温度作为常见的生产过程参数之一，许多的生产过程都与温度的控制有关，温度

Temperature is one of the common production process parameters. Many production processes are related to temperature control. Temperature control is often a balance between cooling and heating, and the boiler is just such a system. When the cooling is greater than the heating, the entire system cools down; on the contrary, the temperature rises; if the temperature is to stabilize, the heating and cooling must be equal. If only feedback control is used for the water temperature control of the boiler inner tank, the flow rate changes quickly and the temperature control lags behind, which leads to the rapidity and poor stability of the system, and the expected control effect cannot be achieved. Therefore, we can introduce the feedforward compensation link to form the feedforward-feedback control system of the boiler inner tank water temperature, so that the main disturbance (flow) change can be quickly compensated, and the system response lag problem can be solved. <br>Programmable controller (plc) is an industrial control computer, a new type of automatic device that inherits computer, automatic control technology and communication technology. It has the characteristics of strong anti-interference ability, low price, strong reliability, and simple programming. This design will focus on Siemens s7-200 (plc) to realize the feedforward-feedback control of the boiler inner tank water temperature, showing the characteristics of the feedforward-feedback control system; at the same time, this design can see that the feedforward-feedback control system is changing with the flow rate. In the case of the main disturbance, the control effect that can be achieved on the water temperature of the boiler inner tank.

Temperature as one of the common production process parameters, many production processes are related to temperature control, temperature control is often the balance of cooling and heating, and boilers are such a system. When cooling is greater than heating, the whole system cools down; If only feedback control is used for the water temperature control of the boiler, there will be rapid flow change and temperature control lag phenomenon, resulting in the rapidity of the system, poor stability, can not achieve the expected control effect. Therefore, we can introduce the feed-forward compensation link to form the bile temperature feed-feedback control system in the boiler, so that the change of the main disturbance (flow) can be quickly compensated to solve the problem of system response lag.<br>Programmable controller (plc) is an industrial control computer, which is a new type of automatic device which inherits computer, automatic control technology and communication technology. It has strong anti-jamming ability, cheap, reliable, simple programming and so on. This design will be around Siemens 7-200 (plc) to achieve the boiler bile temperature feed-feedback control, showing the characteristics of the feed-back-feedback control system, while the design can see the feed-feedback control system in the flow change as the main disturbance, the boiler bile water temperature can be achieved control effect.

温度作为常见的生产过程参数之一，许多的生产过程都与温度的控制有关，温度的控制往往是对冷却和加热的平衡，而锅炉正是这样的一个系统。当冷却大于加热时整个系统降温；反之升温；若要使温度趋于稳定，则加热与冷却就要趋于相等。若是对锅炉内胆的水温控制只采用反馈控制，就会出现流量变化快而温度控制滞后现象，从而导致系统的快速性，稳定性较差，不能达到预期的控制效果。因此我们可以引入前馈补偿环节构成锅炉内胆水温前馈-反馈控制系统，使主要扰动（流量）的变化能够得到迅速补偿，解决系统响应滞后问题。可编程控制器（plc）是一种工业控制计算机，是继承计算机、自动控制技术和通信技术为一体的新型自动装置。它具有抗干扰能力强、价格便宜、可靠性强、编程简单等特点。本设计将围绕西门子s7-200（plc）来实现锅炉内胆水温的前馈-反馈控制，展示出前馈-反馈控制系统的特点；同时本设计可以看到前馈-反馈控制系统在以流量变化为主要扰动的情况下，对锅炉内胆水温可以取得的控制效果。<br>