Measurement apparatus of non-contact toothed disk frequency and method thereof

Abstract

A measurement apparatus of a non-contact toothed disk frequency and a method thereof are disclosed. A toothed band and toothed heads are combined to form a toothed disk. The toothed disk is installed on a large shaft of a water wheel generator. The toothed heads are uniformly installed on the toothed band according to a certain sequence and a certain quantity, directly face and are installed with a speed measurement probe in parallel, and keep a certain induction distance L with the speed measurement probe. The toothed heads, the toothed band and the speed measurement probe form a frequency signal generating unit. When the large shaft of the water wheel generator is rotated, the toothed disk generates a speed pulse along with rotation of the large shaft. Through the speed measurement probe, a pulse signal which generates a set frequency signal and reflects a set rotating speed is sensed. A frequency signal conversion plate processes an interference signal source and the pulse signal. A frequency measurement module measures a pulse width, according to a frequency generated by a square wave, a set rotating speed is calculated and is sent to a PLC controller so that the rotating speed is processed, and correlation information is displayed on a touch screen. The apparatus possesses a self-diagnosis function. When the speed measurement probe generates a fault, a system can automatically reject a fault channel. Through adopting the above mechanism, burst interference can be effectively restrained and a fault signal is removed. A fault tolerance capability of the measurement apparatus is greatly increased and system reliability is improved.

Description

technical field [0001] The invention relates to a measuring device and method for the frequency of a non-contact gear plate, belonging to the technical field of electric automatic control of hydropower plants. Background technique [0002] The speed of the hydro-generator unit is an important parameter for the control and adjustment of the hydro-generator unit, which can enable the unit to complete functions such as starting, stopping, and increasing and decreasing loads. Therefore, high reliability and high precision requirements are put forward for the unit frequency measurement device. It has the advantages of low cost and simple installation, but it also has certain safety risks: the residual pressure signal is seriously distorted at low speed, and its real unit speed cannot be detected through the residual voltage frequency method, resulting in the residual pressure frequency of the unit during startup and shutdown. Disappearance may cause the unit to be out of control;...

AI Technical Summary

Problems solved by technology

In the speed measurement of the gear plate, the processing accuracy of the gear plate is difficult to ensure the accuracy requirements of the speed measurement of the hydro-generator set, and the average filtering method is used to improve the measurement accuracy, which will affect the real-time performance of the frequency measurement

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