Large-sized generator stator core loss detection method and device

Abstract

The invention provides a large-sized generator stator core loss detection method and device. The method comprises the following steps: boosting an output voltage of a test power supply to an excitation voltage; compensating for a reactive component in generator stator core loss by an adjustable compensating capacitor; exciting a stator core with an excitation winding which winds the stator core; detecting current flowing through the excitation winding, and detecting an excitation induced voltage through a measuring winding; inputting the current flowing through the excitation winding and the induced voltage output by the measuring winding into an iron core loss meter to calculate the iron core loss. The device comprises a boosting transformer, the compensating capacitor, the excitation winding, the measuring winding and an iron loss calculating unit. By adopting the large-sized generator stator core loss detection method and device, power capacity required by testing of the large-sized generator stator core loss can be lowered greatly, the size and weight of a test device are reduced greatly in comparison to the conventional test device, transportation and operation become easy; the provided power capacity and quality meet the test requirement, and the power quality of a power plant is not influenced.

Description

technical field [0001] The invention relates to a large-scale generator stator core loss detection technology, in particular to a large-scale generator stator core loss detection method and device. Background technique [0002] The stator core of a large generator is stacked by silicon steel sheets weighing hundreds of tons. In order to verify whether the generator core after manufacture, assembly and maintenance meets the actual requirements, it is necessary to measure the iron core under the specified magnetic density B=1.4T loss. Stator iron loss test is an indispensable test item in the process inspection of the trial manufacturing plant and in the treatment of generator core defects in power plants. Generator stator iron loss test is to use special excitation coil to cause alternating magnetic flux (close to saturation state) inside the iron core, so that the iron core will generate eddy current loss and the temperature will rise. At the same time, use a power meter t...

AI Technical Summary

Problems solved by technology

[0003] In order to complete the stator core loss test of large generators, a large-capacity transformer can be used directly. In this way, the core loss test device is not only bulky in size and weight, it is difficult to transport and erect the test site, but also the single-phase heavy load and low power factor power supply will The three-phase power supply voltage is asymmetrical, resulting in negative-sequence components and zero-sequence components, affecting the power quality of the plant

The test power supply is not universal with the conventional test power supply. The development of the test device requires a large amount of investment, a long construction period, low economic benefits and no capacity increase. It is difficult to meet the needs of the future development of the generator market.

[0004] In order to solve the above problems, domestic scholars proposed to replace the large-capacity transformer required by the generator core loss test with a factory-use 6kV transformer (such as a steam turbine transformer). Although it can solve the power supply problem, this method has poor flexibility and cumbersome test wiring, which is harmful to the factory power supply. The risk is relatively high, and it is not applicable to the actual situation of all power plants

At present, there is no detection technical solution that can effectively solve the power supply for large-scale generator iron loss test

Images