MPS型中速磨煤机运行故障分析及其控制功能改进

ANALYSIS OF FAULTS IN OPERATION OF MPS TYPE MEDIUM SPEED COAL PULVERISERS AND RETROFIT OF ITS CONTROL FUNCTIONS

在分析华能井冈山电厂3号机组及华能福州电厂5号机组MPS型中速磨煤机运行工况及故障现象的基础上,对原磨煤机加载控制功能进行了改进,增加了磨辊未提升跳闸磨煤机逻辑及加载降磨辊时自动减小反作用油压设定值等功能。改进后的控制逻辑实现了磨辊的自动调节、加载曲线调整、油压闭环无差调节等功能。运行结果表明,改进后的控制逻辑克服了原控制逻辑功能单一、整定繁琐的缺点,有效防止了碾磨力与煤量/煤质不匹配时导致的磨煤机振动或堵煤,提高了MPS型中速磨煤机自动控制水平。

On the basis of analysing the operating condition and fault phenomena of MPS type medium speed coal pulverizers equipped for unit no. 3 in Huaneng Jinggangshan Power Plant and unit no. 5 in Huaneng Fuzhou Power Plant,the loading control function of original coal pulverizers has been retro- fitted,the functions,such as logic for tripping the coal pulverizer due to the rollers being unlifted up, and automatic reduction of the set value for reactive oil pressure in case of lowering the rollers for load- ing the coal pulverizer etc. being added. After refrofit, the control logic can realize automatic adjust- ment of the rollers, and regulation of the loading curves,as well as the closed - loop astatic regulation of the oil pressure etc.. Results of operation show that the control logic after retrofit overcomes the de- fects of the original control logic, such as single function and frequent setting etc. , prevuenting effec- tively the vibration of coal pulverizer and coal plugging in the coal pulverizer due to the pulverizing a- bility is unmatch with the coal quantity and the coal quality.