The proportional control mode of the burner achieves rapid response to load changes by dynamically adjusting the fuel-air ratio. Its core lies in establishing a precise matching mechanism between fuel flow, air flow, and heat load demand. This mode typically employs a closed-loop control system, using burner outlet temperature, flue gas oxygen content, or furnace pressure as feedback signals. Through proportional-integral-derivative algorithms or more advanced model predictive control (MPC) strategies, it corrects the opening of the fuel valve and damper in real time, ensuring that combustion efficiency is synchronized with load demand.
On the fuel supply side, the proportional control burner is equipped with high-precision flow valves, such as servo-controlled gas valves or electromagnetically speed-regulated oil pumps, which can linearly adjust fuel output according to control commands. For example, when the load increases, the system first increases the fuel flow, while simultaneously widening the air butterfly valve opening through a linkage mechanism to maintain the air-fuel ratio within the optimal range. This synchronous adjustment avoids incomplete combustion or temperature fluctuations caused by excessive fuel or air alone, ensuring flame stability during load changes.
Air supply-side regulation is equally crucial. Modern burners typically employ variable frequency fans or damper actuators with servo motors, using pressure sensors to monitor duct static pressure and combining this with airflow meters at the burner's front end to achieve precise airflow control. When the load decreases, the system prioritizes reducing airflow to prevent a drop in furnace temperature due to excess air; conversely, during load increases, premixing technology is used to increase air supply in advance, shortening combustion response time. Some high-end burners also incorporate oxygen sensors, directly using the excess air coefficient in the flue gas as the control target to further improve adjustment accuracy.
Optimization of dynamic response relies on improvements in control algorithms. While traditional PID control can meet basic requirements, it is prone to overshoot or oscillation during sudden load changes. Therefore, the industry is increasingly adopting adaptive PID or fuzzy control techniques, adjusting control parameters (such as proportional gain and integral time) in real time to adapt to different operating conditions. For example, at low loads, the system relaxes response speed requirements to prioritize combustion stability; while in high load ranges, it accelerates the adjustment frequency to suppress temperature fluctuations. Furthermore, some burners integrate feedforward control functions, adjusting fuel and air supply in advance by predicting load change trends (e.g., based on boiler feedwater flow or steam pressure signals), controlling response delays to the second level.
Hardware-level innovation is equally important. New burners employ an integrated design, combining fuel valves, damper actuators, and controllers into a single module, reducing signal transmission delays. For example, some gas burners have built-in pressure regulators and zero-point shift devices in their valve assemblies, automatically compensating for the impact of gas pressure fluctuations on flow. Simultaneously, the application of high-temperature and corrosion-resistant sensors (such as ceramic thermocouples and laser oxygen analyzers) improves the accuracy and reliability of feedback signals, providing robust data support for dynamic adjustment.
In practical applications, proportional control burners require parameter tuning based on specific process requirements. For example, in industrial kiln scenarios, multiple load-temperature relationships need to be set according to the material heating curve, with the burner achieving stepped temperature increases by switching preset proportional control parameters. In power generation boilers, it is necessary to coordinate with the turbine speed control system, using burner load regulation to balance steam pressure and avoid unit frequency fluctuations.
Through synchronous proportional regulation of fuel and air, the application of advanced control algorithms, and improvements in hardware performance, the burner proportional regulation control mode has achieved precise and efficient dynamic load response. This technology not only improves energy utilization efficiency but also reduces pollutant emissions by minimizing combustion fluctuations, becoming a key support for modern industrial combustion equipment to achieve flexible production and energy conservation and emission reduction.
