Centrifugal pump cavitation diagnosing method and device

Abstract

The invention discloses a centrifugal pump cavitation diagnosing method and device. The device comprises a signal collection module, a signal conditioning module, a DSP signal processing module, a storage module externally connected with an SD card, a power source and an LCD touch display module. The signal collection module comprises a Hall voltage sensor, a Hall current sensor, a pressure sensor and a temperature sensor. Motor transient current and voltage measured by the Hall current sensor and the Hall voltage sensor are subjected to Hilbert-Huang transform analysis treatment after being pretreated and subjected to removal of power grid power frequency signals, characteristic parameters capable of reflecting centrifugal pump cavitation generation degrees are obtained and compared with parameters of a centrifugal pump which is normally operated under rated conditions, the current cavitation generation degree is calculated, and a relevant alarm is given in time. According to the centrifugal pump cavitation diagnosing method, operation of the centrifugal pump can be monitored in a non-intrusive mode, a traditional monitoring method is simplified, and real-time capability, accuracy and reliability are improved.

Description

technical field [0001] The invention belongs to the research field of fluid mechanical testing methods, and in particular relates to a method and a device for cavitation diagnosis of a centrifugal pump. Background technique [0002] Traditional centrifugal pump cavitation monitoring methods require the installation of many devices such as pressure pulsation sensors and vibration sensors. The test costs are high, the installation is complicated, and most test sites do not have test conditions. The sensorless monitoring technology that emerged in the 1970s can be used to monitor the working conditions of centrifugal pumps. This technology uses the asynchronous motor that drives the pump as a torque sensor, and extracts the characteristics of the pump's operating status by analyzing the time-frequency characteristics of the electrical signal of the motor to realize working condition monitoring and cavitation diagnosis. This technology can greatly reduce the cost of traditional...

AI Technical Summary

Problems solved by technology

This invention uses Fourier transform to analyze the frequency spectrum of the current signal, but the Fourier transform is only suitable for periodic signals and stationary signals, and has no resolution ability in the time domain, and the current signal to be analyzed is a non-stationary transient signal. The results of the Rie analysis hardly have any practical significance

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