Method for directly measuring power angly and inner angle of generator

Abstract

The invention discloses generator load angle and inner electric potential phase angle measuring method adopted rotating shaft key phase signal and machine end voltage phasor. While electric machine is no load, it detects frequency f0, machine end voltage zero cross t10, rotating shaft key phase signal rising edge time mark t20, machine end positive sequence voltage phase angle, inner electric potential phase angle alpha; while electric machine is running, each of them is, t1, t2; the advantages of the invention are that the measuring method has no relation with machine end current, time start point, and generator direct axis and quadrature axis synchronous reactance parameter; it does not need quadrature for machine group rotating speed; and it is not influenced by electric network and machine group disturbance transient state process.

Description

technical field [0001] The invention discloses a method for directly measuring the generator power angle and internal potential phase angle by using the key phase signal of the rotating shaft and the terminal voltage phasor, which is mainly used in the synchronized phasor measurement device of the wide area measurement system (WAMS), and belongs to Power system and its automation field. Background technique [0002] In recent years, large-scale power outages have occurred successively in the United States, Europe, and Russia, which have seriously affected the national economy and social stability. In order to ensure the safe and stable operation of regional power grids, domestic and foreign large power grids, research institutions, and multinational companies have all strengthened the research on dynamic stability monitoring technology of power grids, and successively installed phasor measurement units (PMUs) in hub substations and large power plants to speed up wide-area me...

AI Technical Summary

Problems solved by technology

The 2005 IEEE Asia-Pacific Power Transmission and Transformation Technology Exchange Conference in Dalian, China showed that most of the phasor measurement units (PMU) produced by countries with advanced technology and multinational companies in the world do not have the function of detecting the power angle of the generator and the internal potential phase angle.

[0028] This method of indirect measurement of unit power angle and internal potential phase angle, due to the nonlinearity of the unit excitation curve, the direct-axis and quadrature-axis synchronous reactance parameters of the unit provided by the manufacturer have deviations, and the transient transition process of the motor when the power grid is disturbed leads to calculation errors. , so that the calculation results of the indirect measurement method have large errors and are unstable. In the case of transient disturbances and faults of the power grid or generator, the measurement accuracy of the generator power angle and internal potential phase angle is often not guaranteed

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