The Design Of Digital Controller For Steam Turbine Multi-unit Coordination

Turbine control system is an integral part of the marine turbine, which not only can ensure the normal sailing ship moored at work, but also can improve steam turbine reliability, safety and economy.The current large ships widely used multiple steam turbine with a way to ensure that the power output of the ship.The traditional turbine control systems are designed for single units, can not be completed for more than one steam turbine unit coordinated control,resulting in a ship cornering is not flexible enough,carrier-based aircraft taking off or landing process, ship tilt and other issues.Aiming at this practical problem, we propose a turbine digital control system design to complete the task of multi-turbine group coordinating control.Through the research and simulation of coordinating control algorithms to achieve purpose of tactical maneuver and sail state maintained, Increasing the viability of the ship,playing a protective role in the process of aircraft take-off and landing.Coordinated control system is divided into man-machine interface, the main controller, assist controller: the man-machine interface using LabVIEW virtual instrument technology, by writing PCI device drivers in Windows and Lab VIEW DLL in other ways to achieve the self-development of PCI devices read and write operations, to complete the implementation of coordinated control algorithm;Master controller is based on the PCI bus and FPGA, peripheral circuits including: digital input and output, analog input and output, communication interfaces, and memory modules, completing the multi-unit speed coordination assigned;The core idea of tactical maneuver is that by coordinating four steam turbine speed and improve the ability of the propeller assisted to turn, thus shortening the time and radius of ship cornering. This is done using the steering- turbine coupling mode, the control system is able to automatically adjust the size of the inside corners, outside of various steam turbine speed difference according to ship's rudder angle,thereby increasing torque turning the ship, the ship nimble cornering, to achieve tactical maneuver purposes. Assist controller uses DSP as the main control chip, electro-hydraulic actuators as controlled object, position sensor analog signal as feedback signal, by giving current and voltage signal conditioning electro-hydraulic actuator piston position, controlling turbine inlet valve opening, reaching a single steam turbine speed control purposes.Based on the research and simulation of various coordinated control algorithm is verified through the coordination of the four units speed could shorten the comering radius, reducing the cornering time and feasibility of achiveing synchronizing multiple units speed, so as to achieve the purpose of the tactical maneuver and navigation state maintained. Subjects completed the hardware platform design and build as well as related software programs. By analyzing the results of each part and the whole system debugging, verify the functionality of the controller.