Method for detecting overload crane by detecting power

Abstract

The invention relates to a method for detecting the overload of a crane by detecting the power, comprising the following steps: (1) detecting the working voltage and the working current of an electric motor; (2) calculating the load of the crane according to the following mathematic model: m=KEtaUICOSPhi / gv, wherein the m is the load of the crane, the K is the coefficient, the U is the working voltage of the electric motor, the I is working current of the electric motor, the COSPhi is the power factor of the electric motor, the Eta is the craning efficiency of the crane, v is the ascending speed of the load of the crane and g is the gravity acceleration of the load; and (3) comparing the calculated load of the crane with the rated load of the crane and judging the overload of the crane. The method is used for detecting the overload of the crane by detecting the working voltage and the working current of the electric motor according to the ascending speed of the load of the crane and related parameters provided by the user without using a weight sensor and a standard weight to calibrate, can not be affected by the fluctuation of the voltage and has the characteristics of rapid response speed, high degree of accuracy, wide application range and the like.

Description

technical field [0001] The invention belongs to the field of crane safety protection, in particular to a power method crane overload detection method. Background technique [0002] At present, cranes are widely used in freight yards, workshops and other occasions for hoisting goods. The characteristics of their work are frequent starts, uncertain lifting capacity, and overloading often occurs during the work process. When the crane is overloaded, it will cause damage to the parts of the crane, shorten the service life of the crane, and cause a safety accident in severe cases. In order to prevent the damage to the crane caused by the overload operation of the crane, avoid the dangerous accident of the crane, and prolong the service life of the crane, it is necessary to limit the overload of the crane. The overload limit method of the crane is usually to install a lifting capacity limiter on the crane, and use it to detect the load weight to prevent the crane from overloading...

AI Technical Summary

Problems solved by technology

Its shortcomings are: long reaction time for detecting load weight, inconvenient installation, affecting the lifting height of the load, and narrow application range; The relationship between the current to detect the load weight

The existing problems are: due to many factors affecting the working current of the motor, the actual working current cannot accurately reflect the load weight, resulting in low accuracy in detecting the load weight, poor adaptability to voltage fluctuations, and the need to use standard weights Problems such as cumbersome installation caused by code calibration

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