Diagnosis method for energy saving at cold end of condensing steam turbine

Abstract

The invention discloses a cold end energy conservation diagnosis method for a condensing steam turbine. The cold end energy conservation diagnosis method for the condensing steam turbine comprises the following steps that the exhaust steam temperature (or the back pressure of the turbine), existing before cold end factors change, of the condensing steam turbine is measured; the circulating water inlet and outlet temperatures existing before the cold factors change are measured; the cold end factors which are possible to change are determined, and the parameters, existing before changing and after changing, of each cold end factor are determined; and the exhaust steam temperature existing after the cold end factors change, of the condensing steam turbine is calculated according to the parameters, and the decrease amplitude, generated after the cold factors change, of the back pressure of the condensing steam turbine is obtained. The cold end energy conservation diagnosis method for the condensing steam turbine has the advantages that calculation is easy, the number of needed parameters is small, the precision is high, and implementation is easy; and the defect that during existing cold end energy conservation diagnosis, all the cold end variables are needed is overcome, and real-time high-precision cold end energy conservation diagnosis is achieved.

Description

technical field [0001] The invention relates to the technical field of electric power engineering, in particular to an energy-saving diagnosis method for a cold end of a condensing steam turbine. Background technique [0002] In the thermodynamic cycle of a modern large-scale power station condensing steam turbine unit, the condenser is the core, the low-pressure cylinder of the steam turbine is connected internally, and the water supply system is externally connected to form the cold end system of the power plant. The condenser pressure (i.e. the back pressure of the steam turbine) has a great influence on the economics of the unit. How to reduce the back pressure of the unit as much as possible within the allowable range of the external environment is a crucial task for thermal power plants to save energy. The cold-end factors affecting back pressure mainly include circulating water inlet temperature, circulating water flow rate, condenser cleanliness, condenser thermal lo...

AI Technical Summary

Problems solved by technology

For a running unit, except that the characteristics of the condenser remain unchanged, the other cold-end parameters are constantly changing with the operation adjustment, external environment and unit load; It may be beneficial to start the backup circulating pump when the condenser is clean, but it may be disadvantageous to start the backup circulating pump when the condenser is clean

These problems increase the difficulty of energy saving work at the cold end

[0003] The Beerman formula of the former Soviet Thermal Engineering Research Institute and the "Standards for SteamSurface Condensers" formulated by the American Society of Heat Transfer can calculate the influence of various cold-end factors on the back pressure, but these methods require all accurate cold-end parameters , and most power plants lack real-time parameters such as condenser cleanliness, making it difficult to quantify and calculate the economics of cold-end adjustment or transformation in real time

At present, the cold end optimization of thermal power plants mostly relies on the experience of operating personnel. Some power plants also conduct condenser performance tests without considering changes in condenser cleanliness. However, if this method takes a long time, the test results may be invalid.

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