The "Ultimate Judgment" of Transformer Insulation — Impulse Voltage Generator

In the field of extra-high voltage power transmission and distribution, the insulation reliability of transformers is the cornerstone of grid stability. To verify the transient withstand capability of power equipment against atmospheric overvoltage (lightning strikes), the Impulse Voltage Generator (IVG) has become an indispensable testing tool in high-voltage laboratories.

An Impulse Voltage Generator is a test apparatus designed to generate extremely high transient voltage pulses. By simulating the waveforms produced by natural lightning discharges, it assesses the insulation levels of test objects such as transformers, instrument transformers, insulators, and surge arresters.

The technical core of the generator is based on the renowned Marx Circuit principle. Its operation can be summarized as "parallel charging, series discharging":

• The multiple stages of Main Capacitors are charged in parallel via a high-voltage DC source.
• When the voltage reaches the preset value, the Spark Gaps are triggered. Following the first stage's action, a chain reaction occurs, switching the stages from parallel to series instantaneously.
• The resulting high voltage passes through Front Resistors and Tail Resistors for wave shaping, delivering the standardized impulse wave to the test object.

For manufacturers, this is not just an R&D tool but a "passport" to the global energy market.

• It verifies whether the internal windings, interlayer, and ground insulation designs can withstand the intense electric fields generated by impulse voltages.
• Minor defects undetectable by power-frequency tests will break down under impulse voltage, mitigating operational risks after delivery.
• Compliance with standards like IEC 60060-1 is a mandatory requirement for participating in power grid tenders.

In the high-voltage testing sector, the Impulse Voltage Generator is the benchmark for a manufacturer's technical prowess. By precisely simulating extreme overvoltage environments, enterprises are not only protecting expensive power assets but also building a solid "defense wall" for the stability of the global power grid.