Electronic load apparatus

Abstract

The invention is used to improve load current frequency response characteristics of the tested AC power source apparatus for the AC electronic load apparatus. In the invention, the inductor for compensating the frequency characteristics is added in series with the source of the transistor for control of the load current such that it is capable of greatly improving frequency response characteristics for the load current control feedback loop of AC electronic load. Even at the crossing point where current polarity is changed, AC electronic load is smaller than that of the conventional technique. In addition, the invention can be used in the tested AC power source apparatus where frequency is greatly increased as compared with that of the conventional AC electronic load.

Description

technical field [0001] The invention relates to an AC electronic load device used as a load such as an AC power supply device or an uninterruptible power supply device, especially a tested AC power supply for testing and outputting high-frequency AC power such as a frequency converter power supply and a high-frequency power supply. AC electronic load device for other characteristics. Background technique [0002] figure 1 It is a schematic diagram illustrating the operating principle of the positive half-wave of the AC power source 2 under test in the AC electronic load device 1 of the known technology. The equivalent circuit of the AC power source 2 under test is a series circuit of the sine wave voltage generator E2 and the internal resistance R0, which uses the AC power source under test and the reference signal AC voltage E1 of the same phase to flow a certain load current The load current control circuit constitutes. [0003] figure 1 Among them, through the referen...

AI Technical Summary

Problems solved by technology

[0007] exist figure 2 In the circuit, when the load voltage is one polarity, the transistor driven by the load voltage of the other polarity is in a conduction state through the diode, and operates as an AC electronic load with alternating positive and negative polarities, but because it is It operates as an AC electronic load for high-frequency AC power under test, so the frequency range of the negative feedback loop of the AC electronic load must be extended as much as possible

On the other hand, this negative feedback loop will resonate due to the inductance of the connecting cable and the internal parasitic static electricity of the load transistor, which will have a great impact on the stability of the control system

The known technology uses the feedback circuit of the operational amplifier to perform frequency compensation of the control loop, but since the frequency characteristic of the feedback loop that should respond to high speed is widened, it will cause an overcurrent phenomenon that hinders the transient characteristics of the stability. shoot), linking, or oscillation, and in order to avoid this phenomenon, it is necessary to increase the capacity of the capacitors C1 and C11 of the feedback circuits of the operational amplifiers X1 and X11. If the feedback frequency area is not sacrificed, AC electronic load devices in high-speed areas cannot be reached

Images