The Study On The Control System Of Wicket Gate Adjustment Based On Model Test-bed Of Waterwheel Dynamic Characteristics

Model experiment is a major means in scientific research . Some model experiment is done to solve the problem in engineering. The model tests mainly includes energy test, cavitation test, runaway test and the water thrust in axis test . Though sometimes the current sate and pressure fluctuation tests were done, they can not regarded as the main properties of the hydraulic turbine [1][2]. In the past, the operation of test is mainly on manual ways which measured in optical manner in decentralization. It is in low precision and efficiency, and the measurement of dynamic characteristic can not be carried out. With the development of the theory in modern control, technology in information and the popularization of the microcomputer. Some domestic units begin to rebuild the test-bed of the hydrodynamic machines and they made great improvements .The laboratory on Hydrodynamic Machines of the Department of Dynamic Power in Institute of Hydroelectric Power of Hebei university of engineering , took advantage in the founding of new University , After the amalgamation of Hebei Institute of Architectural technology , North China Institute of Water Conservancy and Hydroelectric Power , Hebei Medical College and Hebei agricultural college . They seized in the opportunity of developing, planned to improve their test-bed of the model hydrolytic turbines using microcomputer to deal with the data acquisition and processing. The studying for the dynamic properties of the hydrolytic turbines will be carried out with the guidance of theory in transient current. In current electric system, the waterpower occupies large proportion. The steady running of the hydro station plays an important role in the normally running of the electric system. In the actual operation of the hydro unit , usually there are some instantaneous variable working stations . The most dangerous one is the moment that the unit suddenly throw off (or increase) the most loads. The blade of the hydraulic turbines may be closed quickly with the function of the governor . It may lead to water hammer in the penstock, then the compressive stress in the penstock will increase suddenly . As the burden of the generator rotor fall to zero , while the sendout of the moment can not change immediately , the rotational speed of the hydraulic turbines unit increases quickly . At the same time, if the load of the generator increases to the full, it may results the quick drop of the water pressure and rotational speed. The controlling system of the opening degree of the vanes is a following turing system at a great degree. After the water level of the reservoir and the tailrace are fixed on, the vanes are the only one which can be adjusted. If they can not be modulated strictly at the rules, the test on dynamic properties of the turbine should fail. Thereby the key of the test is the controlling of the vanes rolling degrees . The experiment also depends on the performance of the controlling system .