Problems and Countermeasures in Operation of 300MW Diesel Generator Set 2

We will continue to introduce the problems in the coordinated control technology operation of 300MW diesel generator set and proposes rectification countermeasures. Secondly, the tracking characteristics of the adjustment valve at the engine side of the diesel generator set and the working condition of the thrust pad of the main engine are under coordinated control. The adjustment valve at the engine side acts according to the pressure curve, strictly maintaining the pressure in front of the valve, making it meet the specified value. Based on this design concept, it can really ensure that the steam parameters, especially the main steam pressure, are qualified.

However, when the load is high, especially at a full load of 300MW, due to inaccurate or even imprecise furnace side adjustment, it leads to over adjustment, resulting in the instantaneous pressure in front of the door exceeding the maximum value of 17 4MPa, so that the bypass system of the diesel generator set will act, and the diesel generator set will be overloaded, which will pose a great threat to the safety of the diesel generator set.

The way to avoid this situation is to not only improve the coordination ability of relevant disciplines, but also consider that the pressure curve setting of the main engine adjustment valve tracking should be smooth, so as to make the adjustment valve action more advanced and not cause the pressure to increase to the limit value, causing consequences. Furthermore, the thrust pad of the steam turbine produced by Dongfang Steam Turbine Factory used by Starlight Power Generation Company requires that the load should not suddenly rise or fall, and the pressure change should be stable. If the fluctuation is severe, There is a possibility of burning tiles and causing malignant accidents, so coordinated control should consider making the parameter curve transition smoothly as much as possible to protect the normal operation of the host equipment.

Finally, the method of defining the load area of the diesel generator set and coordinating the start-up and demobilization of the 300MW diesel generator set of Starlight Power Generation Co., Ltd. has a wide load area and is a power plant with peak shaving capacity. According to the manufacturer's regulations and practice, it has been proven that the auxiliary machines operate well between 300MW and 180MW, and the coordinated control system is applicable in this range.

If the diesel generator set is lower than 180MW, not only the water level and combustion are difficult to control, but also the auxiliary machines, especially the pulverizer, primary air fan and induced draft fan, can not be adjusted normally, which makes the coordination control disordered and may cause accidents. Therefore, in general, the coordination control of Starlight Company should be applied to the load area between 180MW and 300MW. In case of abnormal conditions, timely withdrawal from coordination is an important link to ensure the safety of the diesel generator set, But strict adherence to regulations should be observed when exiting.

Firstly, exit the fuel main control, and then automatically exit the air supply system, the coal mill system, and the boiler main control system, so that the combustion system on the furnace side is no longer controlled by coordinated commands and is stable under one working condition. Then turn off the automatic control of the steam turbine, manually intervene in pressure adjustment, carefully check the switching between constant and sliding pressure, and correct heating value correction methods.

In particular, when the pressure near the 300MW load of the diesel generator set is too high, emergency coordination and manual intervention should be carried out to ensure the stability of the diesel generator set. If the emergency shutdown conditions are met, resolutely implement the principle that 2.5 typical faults should never be tackled. Before the RUNBACK test of the diesel generator set, the operator should cut off the coordination control system in case of auxiliary faults, Manual intervention to keep the diesel generator set stable If the RUNBACK test is completed, it shall be adjusted by the coordinated control system.