Method for implementing fast measurement of inductive winding DC resistance by using constant voltage source

Abstract

The invention discloses a method for realizing the rapid measurement of direct current resistance of an inductive winding by utilizing a constant voltage source. The rapid measurement is realized by utilizing the constant voltage source in a rapid measurement instrument of the direct current resistance of the inductive winding to maintain a constant working voltage, selecting the range according to the resistance range to be tested of a winding of inductive equipment and adjusting the current of a measurement circuit by changing a resistance value of a range circuit; and a circuit of the rapid measurement instrument comprises a power supply device, the range circuit, a millivoltmeter and a control circuit of the constant voltage source. The method can realize the rapid measurement of the direct current resistance of windings of inductive equipment such as transformers, generators, engines, electric reactors and so on, and is suitable for field debugging at construction stages of metallurgical enterprises. The rapid measurement instrument, which has the characteristics of light weight, convenient carrying, simple operation, safety and applicability, of the direct current resistance of windings of inductive loading equipment can be produced according to the method; and the rapid measurement instrument can substitute a double electric bridge and constant current source method to measure the direct current resistance of the inductive windings, and has the advantages of quick measurement speed, strong anti-jamming ability, steady and intuitive readings, and high accuracy.

Description

technical field [0001] The invention relates to a method for measuring the DC resistance of an inductive winding, in particular to a method for quickly measuring the DC resistance of the winding of an inductive load device by using a constant voltage source. Background technique [0002] The measurement of the DC resistance of windings such as transformers, reactors, and motors, as a national standard test item stipulated in the "Electrical Installation Engineering Electrical Equipment Handover Test Standard GB50150-2006", can check the welding quality of the internal wires of the windings, and the connection between the lead wires and the winding wires. Welding quality, whether the specifications of the wire used for winding meet the design requirements, whether the contact between the tap changer, the lead wire and the bushing and other carrier fluids is good, whether the three-phase resistance is balanced, etc. But because the windings of these loads are inductive, especi...

AI Technical Summary

Problems solved by technology

But because the windings of these loads are inductive, especially the large-capacity loads have a large inductance, it is a time-consuming and laborious work to measure the DC resistance by the traditional double bridge

In the past, we used double bridges to measure the DC resistance R of inductive windings such as transformers X The charging time is very long, depending on the voltage level of the device under test, the charging time (each time) can be as little as a few minutes, and as long as tens of minutes. For a transformer with five gears as an example, it can be as little as 2-4 hours. , up to 8-24 hours, there are shortcomings of unstable measurement data, long test time, complicated operation and low safety

At present, similar inductive DC resistance testers sold on the market generally adopt the method of constant current source control for detection, which has the disadvantages of preheating the device, unstable data measurement, and AC power supply for high current.

Images