Opti-Drive
Boiler Automation System
Advanced automation and combustion control for coal-fired steam boilers, using variable-speed drives, PID control and automated monitoring to improve efficiency, reliability and steam production.
Opti-Drive is a fully automatic boiler control system designed for coal-fired steam boilers. The system uses variable-speed drives, PID controllers, pressure transmitters and precision sensors to automatically control combustion, boiler pressure, water level and fuel feed according to steam demand.
Traditional Boiler Control vs Opti-Drive
Traditional system:
DOL motors operate at full speed while mechanical dampers regulate airflow. This can result in unnecessary electrical consumption, less precise combustion control and increased mechanical wear.
Opti-Drive:
Variable-speed drives and PID controllers continuously adjust fan, stoker and pump speeds according to boiler pressure, furnace conditions, water level and steam demand.
Why Opti-Drive?
Opti-Drive provides automatic, modulating control instead of simply switching equipment on and off. This allows the boiler to respond continuously to changing steam demand.
How Opti-Drive Works
Opti-Drive continuously monitors boiler conditions and automatically adjusts the equipment required to maintain efficient operation.
ID & FD Fan Control
Variable-speed drives regulate the ID and FD fans to maintain the required furnace conditions and combustion airflow.
Steam Pressure Control
A pressure transmitter and digital PID controller monitor boiler pressure and automatically adjust the ID fan, FD fan and stoker according to steam demand.
Stoker Control
The stoker speed is automatically modulated to control the amount of coal being supplied to the furnace.
Feedwater Control
A capacitance probe and PID controller continuously monitor boiler water level, allowing the feedwater pump to modulate according to steam demand.
Automatic Coal Feed
An ultrasonic sensor monitors the coal hopper level and automatically controls the coal feed system to maintain the required fuel supply.
Precision Control
During commissioning, Opti-Drive is configured to suit the boiler’s operating requirements. Typical settings may include a 7 bar pressure setpoint with a 0.5 bar differential, with idle speeds of approximately 6 Hz for the ID fan, 5 Hz for the FD fan and 4 Hz for the stoker. The ID fan typically operates within a 38–45 Hz range, depending on the boiler and combustion requirements.
Potential Energy & Fuel Savings
Opti-Drive can significantly reduce electrical and coal consumption by continuously matching boiler operation to actual steam demand. Actual savings depend on boiler condition, operating profile, coal quality, steam demand and other site-specific factors.
Electrical savings: Typically 30%–60%
Coal savings: Typically 5%–12%
Precision Boiler Water-Level Control
Opti-Drive uses a capacitance probe and PID controller to continuously monitor boiler water level. The feedwater pump is modulated to provide only the water required according to current steam demand, helping maintain a stable working level and reduce unnecessary fluctuations in boiler pressure.
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This replaces the traditional pump on/off control method with continuous modulation for more precise water-level management.
Advanced Boiler Monitoring
Opti-Drive provides operators with important operating information directly through the control system interface, including exhaust gas temperature, feedwater temperature, boiler pressure and other operating parameters.
​Exhaust Gas Temperature
Monitoring exhaust gas temperature helps operators optimise combustion, bed height and stoker operation.
Feedwater Temperature
Monitoring feedwater temperature provides valuable information for assessing boiler performance and efficiency.
Benefits of using the Opti-Drive System
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Fully automatic boiler control
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Variable-speed fan and stoker control
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Precise combustion management
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Stable steam pressure
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Modulating feedwater control
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Reduced electrical consumption
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Reduced coal consumption
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Improved boiler efficiency
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Reduced mechanical wear
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Reduced operator intervention
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Improved monitoring and control
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Potential reduction in emissions