In an integrated turbine-driven air compressors system, the computer controlled portion's control unit accepts operator commands to logically process and compute field signals, produce control signal outputs, and use the servo control module to process and conduct post-amplification control of the electro-hydraulic servo valve driven cylinders, which drives the movement of the valves. This controls the amount of steam that enters the turbines, and controls the turbine rotation speed and ensures the air compressor's air volume and air pressure remains unchanged. It also produces control signal outputs to the anti-surge valves, satisfying the compressor's anti-surge requirements.
The advantages of treating the turbine and air compressor as a single controlled entity are:
• Standardised human machine interface
Inter-switchable between the graphical user interface of the air separation unit’s system
• Data sharing
• Convenient to configure
• Flexible control strategy
The air compressor unit’s measuring points can directly participate in the interlocking and control of the turbine
• Ideal control effectiveness
The control cycle is shortened to improve the system’s dynamic response accuracy. The minimum control cycle is 50ms. The rotational speed control accuracy is <±2 rotations / min.
• Convenient communications
• Convenient maintenance
• Highly expandable