The Optimization Of 600 MW Air Cooling Unit Valve Management Of DEH System Of Da-la-TePower Plant

A large number of air cooling steam turbine generator were running in north and northwest of China, where there is rich in coal and shortage ofwater. Due to high parameters of 600 MW air cooling unit, the imbalance distribution of steam, and bigg steam flow force, moderate vibration will be significantly increased. Thus 600 MW air cooling unit cannot input sequence valve adjustment, only adopts throttling, cause loss of control valve throttling, serious impact on the efficiency of the unit load change.At the same time, seasonal changes lead to unit back pressure changes in air cooling, which cause valve throttling losses under the rated load.In addition, due to the differences exist in the process of the steam turbine manufacturing and installation etc, the actual valve flow characteristic curve and DEH valve flow characteristic curve is preset in larger deviation.This deviation may cause slow in load mutation and adjust, difficult in the unit control, affect the security and variable load capacity of the unit. Therefore, whether from the point of improving safety and economic behavior of unit operation, or in terms of unit control, need to optimize the management of valve.There are lots of problems such an when use the sequence valve mode, the #1, #2 watts’ temperature is high, severe EH oil pressure fluctuation and single-sequence valve switch problems of Da-La-Te power plant 600 MW air cooling unit. The author of this paper makes practical application of research management optimization technology.After the optimization of valve management, the unit can not only smooth input sequence valve operation, and in the process of single-sequence valve switching, load fluctuation is less than 5 mw, compared to the original design under the rule of switching load fluctuations decrease more than 90%. At the same time, after the input sequence valve, the economy has been obviously improved, for exampleat 330-430 MW unit load the efficiency increase by about 40% on average, are converted into pressure rated runtime power generation coal consumption lower about 3 g/kWh, theefficiency significantly increased, and energy saving effect is obvious.Each unit by the average power of 420 MW in 4500 hours for calculate, festival coal per unit about 3 g/kWh*4500*420MWh=5670 tons of standard coal, each tce calculated at 240 Yuan, equivalent to about 1.36 million yuan. Saving standard coal 11340 tons every year by 2 units. Equivalent to # 7, # 8 machine increases the value of 2.72 million Yuan, at the rate of 15%, the new tax is 408000 Yuan, the economic benefit is very significant, meet the requirements of the technical agreement, and have been achieved the ideal goal of the valve management optimization.