Method for measuring rotor speed of turbo generator and device thereof

Abstract

The invention discloses a method for measuring the rotor speed of a turbo generator and a device thereof. The method comprises the following steps: converting the rotor speed into a pulse electrical signal through a sensor; carrying out F / V conversion on the pulse electrical signal, wherein U(f) refers to the converted voltage signal, f refers to the pulse electrical signal, f1 and f2 refer to two predetermined pulse electrical signal values, Umax refers to a predetermined voltage value; carrying digital-to-analogue conversion on the voltage signal after the F / V conversion; and converting the voltage signal after the F / V conversion into digital quantity through a data acquisition unit. In the method, F / V conversion is carried out on the pulse electrical signals by stages, with respect to the voltage signal which is converted according to the U(f) = F*k1 linear form in prior art 2, because k is more than k1, the frequency range corresponding to the converted voltage signal in the predetermined scope is small, and the caused linear error is also small, the measurement is insusceptible to interference wave, and the measurement error of the rotor speed is small.

Description

technical field [0001] The invention relates to a steam turbine generator, in particular to a method and a device for measuring the rotational speed of a turbine generator rotor. Background technique [0002] Many measuring devices for the rotor speed of turbogenerators are realized by sensors, F / V (frequency / voltage, frequency / voltage) conversion units, and data collectors. When the rotor rotates, the sensor converts the rotor speed into a pulse electrical signal, which is converted into a voltage signal by the F / V conversion unit, and then the voltage signal is converted into a digital quantity by the data collector to complete the measurement of the turbine generator rotor speed. [0003] In the load shedding test of the steam turbine generator set, the rotor speed changes very rapidly, and the rotor speed can reach 280-400r / min within 40-110ms of initial soaring, which has high requirements for the measurement accuracy and response speed of the rotor speed. Analysis It ...

AI Technical Summary

Problems solved by technology

The measurement range of the measuring device of the prior art 2 is 0-5000Hz, and the output is 0-5V. After analysis, the measuring device is affected by white noise, and there is an interference wave of 20mv, which is equivalent to 20r / min. The frequency range of the load rejection test (2750~3250Hz) has an average signal-to-noise ratio and large measurement errors

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