Impulse Voltage Tester Oscillation Suppression Circuit
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Impulse voltage tests on electrical devices with inductance and capacitance, such as transformers, often result in oscillating waveforms that cause polarity reversal, leading to unintended voltage stress and inaccurate evaluation of withstand voltage performance, as the second half waves do not conform to normalized standard waveforms.
Innovation Solution
An impulse voltage tester with a voltage generation circuit and an oscillation suppression circuit, featuring a discharge switch and capacitor, which becomes conductive after polarity reversal to apply a voltage from a capacitor charged to the same polarity as the first half wave, suppressing unnecessary voltage stresses on the electrical device.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If an impulse voltage test is performed on an electrical device with inductance and capacitance, then the withstand voltage performance can be evaluated, but the oscillating waveform causes polarity reversal and applies unintended voltage stress to the device
Solution Approach 1:
The patent extracts and eliminates the harmful second half waves from the impulse voltage waveform while preserving the useful first half wave. The oscillation suppression circuit selectively removes the oscillating components that cause polarity reversal and unintended voltage stress, allowing accurate evaluation of withstand voltage performance without the harmful effects of subsequent half waves
Solution Approach 2:
The patent converts the harmful oscillating waveform into a beneficial controlled waveform. By using the oscillation suppression circuit with discharge switches and capacitors, the naturally occurring oscillations are transformed into a controlled process where the timing and magnitude of voltage application are optimized to eliminate harmful second half waves while maintaining the integrity of the first half wave for accurate testing
2Device complexity
If the impulse voltage waveform allows second half waves to occur, then the circuit operation is simpler, but the evaluation accuracy deteriorates due to unintended voltage stress
Solution Approach 1:
The patent introduces an oscillation suppression circuit as an intermediary between the voltage generation circuit and the electrical device under test. This intermediary circuit, consisting of discharge switches and capacitors, mediates the waveform by suppressing unwanted oscillations and preventing harmful second half waves from reaching the test device, thereby improving measurement precision without significantly complicating the overall system operation
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution improves the accuracy of withstand voltage performance evaluation by preventing or reducing voltage stresses not assumed in the impulse voltage test, ensuring the first half wave conforms to standard waveforms without affecting it and suppressing unnecessary second half waves.
Implementation Method 1
The discharge switch becomes conductive when a voltage difference between the first electrode and the second electrode is greater than a discharge voltage corresponding to the spacing between the first electrode and the second electrode
Implementation Method 2
The capacitor is connected between the second electrode and the second terminal. When the impulse voltage applied to the electrical device has an oscillatory waveform, the discharge switch of the oscillation suppression circuit is rendered conductive after the polarity of the waveform is reversed from that of the first half wave and before the peak value of the second half wave is reached, so that a voltage can be applied from the capacitor charged to the same polarity as that of the first half wave to the first terminal
Data Source
AI summary
An impulse tester according to the present invention includes a first terminal, a second terminal, a voltage generation circuit, and an oscillation suppression circuit. The oscillation suppression circuit includes a discharge switch and a capacitor. The discharge switch has a first electrode and a second electrode. The first electrode is connected to the first terminal. The second electrode is disposed at a spacing from the first electrode. The discharge switch becomes conductive when a voltage difference between the first electrode and the second electrode is greater than a discharge voltage corresponding to the spacing between the first electrode and the second electrode. The capacitor is connected between the second electrode and the second terminal.