Discussion on large boiler control

The first question should be achievable; I’m not quite sure about the second one – is it meant to reduce the air intake to the boiler at the time of ignition? Increase air volume after normal ignition? The key point is that, for the furnace, such operations cannot immediately change the pressure inside the furnace; therefore they are pointless. If such operations must be carried out, it should be possible to achieve such adjustments through a PLC.

Program controllers have fixed program settings; the steps and values cannot be changed. However, if the actuator has a manual function, it can be adjusted manually when needed. The PLC can be used to contact the control manufacturer to change the value settings.

Program control should be implemented automatically. The air volume should be adjusted via frequency conversion (or by adjusting the opening of the dampers); therefore, at the ignition point, the air volume is set according to the amount of fuel specified for ignition.

This post was last edited by pzhmotor on 2010-6-24 at 12:19. I have never used a furnace that operates on gas; I studied industrial automation in school, so I still have some basic knowledge, and I am familiar with the ignition and control processes of gas-fired rotary kilns. The following information is provided for reference: 1. In gas burners, the controller is powered first, followed by the motor; can this high-voltage motor perform such a function? It is necessary to clarify whether the high-voltage motor is controlled by a “program controller”? Whoever gets power first – just close the switch first for them. “\"Being powered on\" means starting up; in that case, the control circuit for the high-voltage motor is the same as that for the low-voltage motor, making it easy to implement. (Both PLCs and traditional control circuits can achieve this.) 2. Can the electric actuator of the high-pressure motor damper also be reduced in size simultaneously when the burner is ignited? Turn up the heat high at the same time? Based on the description, achieving such proportional control is not difficult. In practical applications, what needs to be determined is which detection signal should be used as the basis for \"reducing\" or \"increasing\" the level. When a gas burner is ignited, it relies on a sophisticated control system that monitors parameters such as oxygen content and pressure; if these values do not meet the required specifications, a safety interlock prevents ignition. The basis for opening it up can be a flame detector, temperature, or reference exhaust oxygen content. Usually, after the detection signal is determined, PI(D) control is used to achieve automatic control of the actuator. (It is also a mature technology; it can be controlled using PID controllers, or through PLCs or DCS systems.) It is recommended that the original poster consult in detail about the control principles of gas boilers before proceeding with further work. The gas system cannot be modified arbitrarily according to one’s own ideas, as this could lead to safety accidents due to inadequate consideration. Additionally, variable frequency drives can also be used with high-voltage motors; if the load fluctuates significantly, it is possible to avoid using actuators to control the dampers (the investment in variable frequency drives for high-voltage applications is higher).