Scanning frequency method for testing large turbine generator set torsional vibration mode

Abstract

The invention relates to a measurement and test method for an axial torsional vibration mode of 300MW, 600MW, 1000MW turbine-generator set in a large-scale thermal power plant, and discloses a detecting method for an on-line dynamical frequency sweeping the axial torsional vibration mode by working a pumping signal on the excitation of power generator and combing the closed-circuit test which obtains the optimized response by a dynamically and continuously adjusting the pumping signal. The pumping signal with the mode characteristic is outputted through a method of dynamically on-line frequency sweeping. The excitation system of the turbine-generator set produces a controllable electric torque in the turbine-generator set through the excitation system so as to excite the axial torsional vibration of the turbine-generator set. Besides, the intensity of the axial vibration is measured to assure the fixed axial mode of the turbine-generator set. The method can measure the mechanical fixed frequency that is the axial torsional vibration mode of the turbine-generator set accurately, and is the basic research for solving the secondary in-phase vibration harm of the turbine-generator set. The invention is used for preventing, restraining and protecting the generator set and the power network from producing secondary in-phase vibration.

Description

technical field [0001] The invention relates to electric power systems, large-scale thermal power plants, and industrial fields requiring turbogenerator sets or large-capacity motors Background technique [0002] Large-scale thermal turbine technology is one of the key equipment of major equipment in my country, and the large-scale construction of power plants is the guarantee for the rapid development of my country's industry. The shafting of high-power units has the characteristics of light weight and flexibility, multiple supports, large span, and high power density. The utilization factor of generator materials is improved, and the power density of the shafting section is relatively increased. The natural frequency spectrum of the system is relatively dense, and the energy induced by vibration is low; at the same time, the power grid is also developing in the direction of a large ultra-high voltage area. The application of advanced power transmission and distribution an...

AI Technical Summary

Problems solved by technology

At present, the domestic method of testing this content is to do various disturbance tests after the large-scale generator is running, including unit synchronization, de-loading, line switching, unit load shedding, etc. It cannot guarantee that the test is sufficient and effective each time, and it is harmful to the unit. and power grid operation are somewhat destructive

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