Independent low-pressure heater and drainage pump flow soft measurement-based method for measuring and calculating pump efficiency

Abstract

The invention relates to an independent low-pressure heater and drainage pump flow soft measurement-based method for measuring and calculating pump efficiency. A thermodynamic system of the invention consists of an independent low-pressure heater (LH) and a drainage pump. The method comprises the following steps of: acquiring the water pressure at the outlet of the heater with the drainage pump from a database of a heat-engine plant supervisor information system (SIS) or a decentralized control system (DCS); acquiring the water temperature at the inlet of the drainage pump; acquiring the real-time current and voltage, efficiency and power factor of a motor of the drainage pump; acquiring the water pressure at the inlet of the drainage pump and the drainage average specific volume through calculation; calculating the pressure difference of the drainage pump, namely the difference between the water pressure at the outlet of the heater with the drainage pump and the water pressure at the inlet of the drainage pump; calculating the flow of the drainage pump by using a method for measuring and calculating the flow of the independent low-pressure heater and drainage pump of a heat-engine machine set based on energy balance; figuring out the output power and the input power of the drainage pump according to the data; and calculating a ratio of the output power to the input power, namely the efficiency of the drainage pump.

Description

technical field [0001] The invention relates to a method for measuring and calculating pump efficiency based on the soft measurement of the flow rate of an independent low-pressure drain pump, and belongs to the field of soft measurement. Background technique [0002] With the expansion of the capacity of thermal power units, the influence of the heat recovery system on the units has attracted more and more attention. In regenerative heaters, in order to improve the regenerative effect of surface heaters, low pressure heaters are usually equipped with a drain pump. The measurement of the efficiency of the drain pump has an important impact on the performance monitoring of the drain pump, the optimal operation of the drain pump, the analysis of the operating status of the heater group, and even the heat balance calculation of the heat recovery system. Therefore, it is necessary to monitor the efficiency of the drain pump. At present, there are no reports on the calculation ...

AI Technical Summary

Problems solved by technology

When calculating the input power of the drain pump, it is impossible to extract the instantaneous power value, which affects the calculation of the efficiency of the drain pump. When calculating the output power of the drain pump, it is necessary to calculate the flow of the drain pump. At present, adding a drain pump measurement point in the thermal system, It is necessary to select a suitable flowmeter according to its performance requirements, fluid characteristics, installation requirements, environmental conditions and cost factors, etc.

After adding this measuring point, there will be a certain impact on the flow rate, and it will take manpower and material resources to maintain it

Therefore, it is time-consuming and labor-intensive to directly solve the problem of the drainage pump flow from the hardware aspect, and there are many inconveniences

These problems in the flow measurement of the drain pump directly affect the measurement of the output power of the drain pump

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