Study on Automatic Control of Water Transfer Projects before Freezing

China is a country with disaster of severe ice conditions and ice jam. As more and more large-scale water transfer projects such as the South-to-North Water Transfer Project, research of formation mechanism of ice jam and the numerical model of water transfer in winter is urgent. Reasonable and feasible water transfer mode must be put forward to improve the flow condition in freezing period and reduce the harm caused by ice jam. When the flow velocity is below 0.4m/s, there will be a stable ice cover on the top of canal system, greatly relieving the probability of forming suspending ice jam. This paper tries to determine a automatic control model with 3 days´ cold current forecast in advance. With the control model, flow velocity all can drop to 0.4m/s after the coming of cold current, and there is no overtopping and harm to canal lining.