How to consider the effect of shunt inductance?
How to consider the effect of shunt inductance? In essence, electrical components all have inductive components, but in different scenarios, the main characteristics displayed are different. We only say which is a resistive component and which contains an inductive component, mainly considering two factors. One is the loop frequency. The higher the loop current frequency, the greater the rate of change of the magnetic field, and the greater the induced electromotive force. Another factor is the size of the resistance of the shunt itself. It can be known from the process of measuring the current of the shunt that it mainly measures the terminal voltage of the shunt. When the internal resistance is large, a small amount of induced electromotive force is superimposed on the terminal voltage, which does not have a significant impact on the accuracy, so naturally there is no need to consider the inductance. problem.
The material selected for the shunt is generally manganese copper, constantan or nickel-chromium alloy. On the one hand, the temperature coefficient is considered, and on the other hand, the resistance value is increased within the allowable range to cover the influence of inductance. The internal resistance cannot be too small, but it cannot be too large in order to avoid a lot of heat generation. This dilemma is an important factor affecting the application of shunts in high current loops.
Although the power supply of electric vehicles is called high-voltage direct current, the power fluctuation during driving has a very large current change rate, and the measurement of the shunt may also be distorted at some moments.
High-end electric vehicles have higher and higher requirements for power performance, and a few seconds per 100 kilometers will appear in the first show copy. The shunt is probably not quite suitable for their requirements. In low-speed, low-power models, the splitter should still have a place. Without much quantitative data, let’s discuss qualitatively first.
