Tham khảo tài liệu 'gas turbine engineering handbook 2 episode 15', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Control Systems and Instrumentation 685 equivalent engine time hours Figure 19-21. Equivalent engine time in the turbine section. 4. Bearing failure. The symptoms of bearing problems for a turbine are the same as for a compressor. 5. Cooling air failure. Problems associated with the blade cooling system may be detected by an increase in the pressure drop in the cooling line. 6. Turbine maintenance. This should be based on equivalent engine time which is the function of temperature type of fuel used and number of starts. Figure 19-21 shows the correction that can be applied to running hours for intermittent-duty units with high-start stop operation. Turbine Efficiency 1. With the current high cost of fuel very significant savings can be achieved by monitoring equipment operating efficiencies and correcting for operational inefficiencies. Some of these operational inefficiencies may be very simple to correct such as washing or cleaning of the compressor on a gas turbine unit. In other cases it may be necessary to develop a load-distribution program that achieves maximum overall efficiency of the plant equipment for a given load demand. 686 Gas Turbine Engineering Handbook 2. Figure 19-22 shows the significant dollar cost penalties that occur when operating a turbine at a very small percentage efficiency degradation. 3. Table 19-8 shows a load-distribution program for an power station of steam turbines and gas turbines. The selection of equipment and their loading for the most efficient operation can be programmed when the efficiency of individual units are monitored. The program Operating Hours Figure 19-22. Savings versus efficiency. Control Systems and Instrumentation 687 Table 19-8 Load Sharing Program Description of utility Plant Units Unit Design MW Turbine Type Efficiency at Design Output Point 1 Steam 22 2 Steam 22 3 Steam 24 4 Steam 24 5 Steam 24 6 Steam 25 7 Steam 30 8 Steam 23 9 Gas 21 10 Gas 21 .
