DC high-voltage generators are indispensable in modern electrical testing, providing stable and controlled high-voltage DC power for assessing insulation integrity, dielectric strength, and overall reliability of high-voltage equipment. These systems are critical for applications ranging from power cable testing to evaluating transformers and circuit breakers, ensuring compliance with international standards such as IEC and DL/T 848.1-2019 :cite[6]. This article delves into the technological advancements, design principles, and practical applications of DC high-voltage generators, highlighting their role in enhancing measurement accuracy and operational safety.

Modern DC high-voltage generators leverage innovative topologies to achieve high voltage gain and efficiency. For instance, quadratic DC/DC converter designs integrate coupled inductors with voltage multiplier cells to minimize voltage stress on switching devices while ensuring continuous input current and ultra-high voltage gain :cite[1]. In high-power scenarios, cascade generators utilize multiple stages of voltage multiplier circuits connected in series. A notable example is a 1.2 MV system that employs 40 stages, each producing 30 kV, achieving exceptional voltage output with minimal ripple :cite[9]. Such designs often incorporate advanced insulation materials, such as SF6 gas at 0.8 MPa, to manage electrical stresses and maintain stability under high loads :cite[9].

Control systems have evolved significantly, with digital signal processors (DSPs) and microcontrollers like the MCS-8098 enabling precise regulation of output parameters. These systems facilitate automated voltage ramping (e.g., 0.5–9.9 kV/s), real-time monitoring of voltage and leakage current, and robust protection mechanisms against overvoltage or breakdown events :cite[5]:cite[7]. For example, DSP-based controllers integrate phase-shifted full-bridge inversion technology to ensure rapid response and minimal ripple, critical for sensitive applications like insulation diagnostics :cite[7]. Additionally, electromagnetic compatibility (EMC) measures, such as shielding and photoelectric isolation, are employed to mitigate interference in high-noise environments :cite[5].

Compliance with technical standards is paramount for reliability and safety. Standards like DL/T 848.1-2019 outline requirements for voltage accuracy (e.g., ±1% deviation within 60 seconds), ripple coefficients (≤1%), and insulation testing protocols :cite[6]. These guidelines ensure that generators meet rigorous performance criteria for dielectric withstand tests on cables and other capacitive loads. Moreover, international standards, including IEC 60270 and GB/T 26217-2019, emphasize electromagnetic compatibility and measurement accuracy, supporting the global adoption of these systems in diverse industrial settings :cite[8]:cite[10].

In practice, DC high-voltage generators are vital for preventive maintenance and quality assurance. They enable precise leakage current measurements during insulation resistance tests, identify weaknesses in power transmission cables, and validate the dielectric strength of industrial equipment. Features like programmable test sequences and automated discharge circuits enhance user safety, while modular designs allow for scalability across voltage levels (e.g., from 60 kV to 300 kV) :cite[10]. As renewable energy and smart grid technologies advance, the demand for high-efficiency, compact generators with digital interfaces will continue to grow, driving further innovation in this field.