A virtual instrument-based DC inductance testing system and method

Abstract

The invention provides a system for testing a DC inductor based on a virtual instrument. The system comprises a control board card, a capacitor bank connected with the two ends of the DC inductor to be detected, a charging circuit for charging the capacitor bank according to the charging command signal of the control board card, a discharging circuit for enabling the capacitor bank to discharge to the DC inductor to be detected according to the discharging command signal of the control board card, and a data acquisition circuit; the data acquisition circuit comprises a low-speed acquisition card and a high-speed acquisition card, as well as a PC in connection communication with the two acquisition cards. The testing method comprises 1) initiating the testing system, 2) performing input setting on the parameters of the testing parameters, 3) acquiring the data of the DC inductor to be detected, 4) processing the set parameters and the acquisition data by use of Levenberg-Marquadt algorithm based on an LCR discharge time current function, thereby obtaining the nonlinear parameter estimated values f, g and h of the LCR discharge time current function, and 5) obtaining the DC inductance and the DC resistance of the DC inductor to be detected according to a formula.

Description

technical field [0001] The invention relates to the technical field of DC inductance testing, in particular to a virtual instrument-based DC inductance testing system and method. Background technique [0002] The so-called inductor refers to a common electronic device that forms a magnetic field induction in the coil after the air-core or iron-core coil passes the current, and the induced magnetic field will generate an induced current to resist the current passing through the coil. It is mainly used for voltage conversion, signal Coupling, resonance, electromagnetic induction and other circuits. According to whether the direction of current flow in the coil changes, it is divided into AC inductance and DC inductance. [0003] Traditional inductance measurement methods are mainly for AC inductance, which can be divided into voltammetry, LCR meter method and resonance method. Voltammetry can provide a wide range of AC and DC excitation amplitudes, but the optional frequency...

AI Technical Summary

Problems solved by technology

The oscilloscope method is "a method for measuring inductance based on a half-bridge circuit" proposed in "Power Electronics Technology" 2008, 42(7): 40-42. This method can provide excitation current conditions similar to the actual working conditions of the inductor, and It can fully reflect the dynamic magnetization characteristics of the inductor and obtain more reference value inductance values. However, this method uses an oscilloscope to test the current and voltage waveforms of the charging and discharging of the inductor to be tested, and then performs data processing to obtain the intuition curve. It is inseparable from expensive High-bandwidth digital oscilloscope, and the degree of automation is not high. This method is also a method of estimation and intuition commonly used by customers for large DC inductance or power inductance manufacturers. It is relatively primitive

In the prior art, there is no feasible virtual instrument system and test method for DC inductors. Since none of them can reproduce the working environment of DC inductors, they cannot accurately measure their corresponding parameters, and each has its own inability Weaknesses and drawbacks to overcome

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