In the factory testing process of transformer manufacturing enterprises, the structural design of testing equipment is often an underestimated but far-reaching factor. A large and difficult to transport series resonant device not only occupies valuable factory space, but also consumes a lot of manpower and time costs in frequent workstation allocation. HV Hipot Electric Co., Ltd. (referred to as “Wuhan HVHIPOT“) has been deeply involved in the field of high-voltage electrical measurement for nearly 22 years. Its HVHIPOT series variable frequency series resonance test device is designed with modularity and lightweight concepts as its core, providing a flexible and efficient structural solution for transformer factories.
Four unit independent splitting, modular combination covering the entire scene
The tested products of the transformer factory cover a wide range of voltage levels and significant differences in capacitance, from distribution transformers to 500kV level large power transformers. A fixed configuration testing device is difficult to meet diverse factory testing requirements.
The Wuhan HVHIPOT series series series resonant device adopts a modular design, with the main body divided into four independent units: variable frequency control power supply, excitation transformer, reactor, and capacitive voltage divider. Each unit can be flexibly combined according to the capacitance of the test sample and the test voltage, adapting to different voltage levels from 10kV to 750kV. Taking the HVHIPOT-75kVA/75kV scheme as an example, the device is equipped with three reactors, each with a capacity of 25kVA/25kV/1A/110H; The HVHIPOT-405kVA/270kV scheme is equipped with 6 reactors, each with a capacity of 67.5kVA/45kV. Through the series or parallel combination of reactors, a set of devices can cover various test scenarios from 10kV cables to 110kV main transformers.
This modular structural design eliminates the need for transformer factories to purchase equipment separately for each voltage level. A single device can achieve “one machine for multiple uses”, greatly reducing the cost of repeated equipment investment.
Single piece lightweight design, bidding farewell to cranes and multi person handling
Transformer testing is usually conducted in the factory building, but the transportation of equipment between different testing stations is the norm. Traditional experimental equipment has a large volume and weighs hundreds of kilograms per piece, often requiring the use of cranes and 7-8 operators to complete the handling and positioning.
The Wuhan HVHIPOT series has implemented the concept of lightweight throughout the entire design phase. The device is lightweight and easy to use on site. Taking the reactor as an example, the single section design ensures that one operator can complete the handling and assembly installation. For large capacity resonant devices, Wuhan HVHIPOT has introduced variable frequency power supplies, dry-type transformers, and air core reactors that can be used in parallel. When high power is required, multiple low-power devices can be used in parallel. This design eliminates the need for cranes for high-capacity resonant devices above 1000kVA, and reduces the personnel configuration from the industry’s conventional 7-8 people to 2 people to complete the testing work.
The weight and volume of the equipment are only 1/10 to 1/30 of traditional equipment
The structural advantages of series resonance technology itself have been fully reflected in the product design of Wuhan HVHIPOT. The series resonant power supply eliminates the need for bulky high-power voltage regulating devices and ordinary high-power power frequency test transformers. The resonant excitation power supply only requires 1/Q of the test capacity, greatly reducing the weight and volume of the system.
The weight and volume of Wuhan ultra-high voltage HVHIPOT series equipment are generally 1/10 to 1/30 of ordinary testing devices. This level of reduction directly translates into the effective release of space in transformer factory buildings – testing equipment that originally required specialized zoning areas can now be flexibly deployed between different workstations, without the need for fixed heavy equipment foundations and large areas of land occupation.
Balancing portability and adaptability to outdoor and complex environments
The testing requirements of transformer factories are not limited to the factory building. Some large transformers require final testing before leaving the factory in outdoor assembly areas or customer sites, which places higher demands on the portability of the equipment.
The lightweight design of Wuhan HVHIPOT series is suitable for complex outdoor and high-altitude environments, without the need for large auxiliary equipment, greatly reducing the difficulty of on-site operations. In response to the unstable power supply conditions on site, all variable frequency power supplies of the company can be used normally when the power supply voltage fluctuates by ± 20%. For variable frequency power supplies with a capacity of less than 15kW, adjusting the input voltage to AC220V while outputting 100% power solves the practical problem of difficulty in obtaining AC380V power supply on site.
Core component quality assurance, structural reliability
The lightweighting of structural design cannot be achieved at the expense of reliability. The Wuhan HVHIPOT series hollow reactors are filled with DuPont materials from the United States and sealed with special processes to reduce internal partial discharge to a low value, thereby improving reliability and safety. The equipment adopts Schneider ABB、 Siemens and other internationally renowned components have further enhanced the reliability of the products.
For transformer manufacturing enterprises, the structural design of the testing equipment is not only related to the usability of the equipment itself, but also directly affects the testing efficiency, labor costs, and utilization of factory space. The Wuhan HVHIPOT series series series series resonance test device provides transformer factories with a structural solution that can withstand long-term use tests with the flexibility of modular combination and the convenience of single piece lightweight.