The Investigation Of CODAD Control System

CODAD marine power plant is impelled by single diesel in lower speed, while in higherspeed, it will be impelled by double diesels correspond. This device can enlarge the usage ofdiesel, making the behavior under low loads economical. With the development of shipbuildingtechnology and the demand of modern ship, the CODAD power system will of course have agreat future.Twin engine incorporation control system is the key point of combined power plant, how tomake the twin engine work smoothly, how to make the twin engine splitting, and how to get agood power distribution when the system in any work states are the problems should be solved inthe research of twin engine system.In this thesis, four kinds of controlling methods are analysised, in the end, we use the powerequalization control method with master and slave mode. The system has two parallel operationcontrollers, which are used to control the diesel and hydraulic coupling. When the CODADsystem works in the parallel operation mode, the controller can recognize the master or the salvediesel automatically. The master diesel keeps working in its rated speed, adjusting the slave oneby changing the speed to satisfy the power distribution requirement, realizing the purpose ofbalance control over the twin diesels incorporation system.As the parallel operation controller plays a key role in the controlling system, a specialresearch is conducted. Through the studying of the IO signal of the controlling system, wedesigned the parallel operation controller which was based on based on ARM7, it obtained2channel of4-20mA output,4channel of4-20mA output,8channel of digital output,16channelof digital input. The parallel operation controller obtains the function of start, stop, parallel, split,speed adjust, load equalization control and part of security features.Based on the thesis research, a series of experiments were successfully conducted inCODAD marine power plant of the institution No.711, including single diesel propulsion、Twinengine incorporation propulsion and Twin engine incorporation emergency reversing these threecases, the coming out conclusions show that, this control system can work stability. This production has a satisfying controlling effect, it is deserved to be promoted in practice wildly.