2。方案设计·······················································4

2。1系统总体方案框图设计··········································4

2。2锅炉温度控制框图设计··········································5

3。系统的硬件控制系统设计·········································6

3。1 PLC控制器的选择··············································6

3。2热电式传感器·······································。·········11

3。3 可控硅加热装置··············································11                           3。4 变频器······················································12

4。系统的软件设计················································12

4。1 PID控制器的设计·············································12