Method for calibrating voltage or current of frequency converter, frequency converter and system

Abstract

The invention discloses a voltage or current calibration method for a frequency converter, a frequency converter and a system, and relates to the technical field of frequency converter control. The calibration method includes the following steps: obtaining the actual effective value of the voltage or current input or output by the frequency converter, and Obtain the sampling effective value of the voltage or current collected by the frequency converter; calculate the deviation multiple according to the actual effective value and the sampling effective value, and calculate the calibration sampling coefficient of the frequency converter according to the deviation multiple; use the calibration sampling coefficient to analyze the voltage or current collected by the frequency converter current for calibration. The invention calculates the calibration sampling coefficient of the voltage or current collected by the frequency converter, and uses the calibration sampling coefficient to calibrate the voltage or current collected by the frequency converter. The calibration process basically does not require manual intervention, and the voltage or current collected by the frequency converter can be quickly realized. calibration.

Description

technical field [0001] The invention relates to the technical field of frequency converter control, in particular to a voltage or current calibration method for a frequency converter, a frequency converter and a system. Background technique [0002] At present, in the control of high-voltage frequency converters, we need to sample the voltage or current of the input or output frequency converter in real time for control, such as overvoltage and overcurrent protection. Due to the influence of external factors (temperature, humidity, etc.), the parameters of some analog devices such as some resistors, capacitors, and operational amplifiers in the sampling circuit of the frequency converter will change. The value of the sampling coefficient is uncertain under the influence of external factors at different temperatures, resulting in A certain deviation occurs in the instantaneous value of voltage or current sampling, which will cause deviation or even error in the control of the...

AI Technical Summary

Problems solved by technology

[0004] The embodiment of the present invention provides a method for calibrating the voltage or current of a frequency converter, a frequency converter and a system, so as to solve the problem of manually adjusting the sampling coefficient of the frequency converter multiple times in related technologies, which takes a long time and requires high technical requirements for personnel. question

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