On the occasion of the workshop "Transformers - Operation and Diagnostics", the following was presented by ABB AG - Engineering Solutions - Halle plant exhibited the world's largest mobile surge voltage test system.

After production in the factory, power transformers undergo a variety of tests to verify production quality and design. A surge voltage test is also carried out to test the resistance to overvoltages from switching operations and atmospheric discharges (lightning).

Power transformers are required in the grid, but also at power plants, whereby after installation it is not always technically possible (as the infrastructure may be dismantled) or economically viable to transport these transformers to a factory for repair. A mobile repair workshop is therefore set up on site and the corresponding tests must then be carried out. Testing with surge voltage is also necessary if the performance parameters are increased or the design is changed - both of which can also be carried out on site. Of course, the system can also be used in the factory if a stationary system fails.

This impressive test system, which can generate an impulse voltage of up to 1.8 million volts (with a surge voltage of 1.3 MV with a switching impulse voltage) with an energy of up to 300 kJ, was set up and exhibited at the university in Zittau. The other special features of this system are its immediate usability due to the selected components, the availability of fault-tolerant surge capacitors and the avoidance of mineral oil as insulating oil for greater environmental compatibility.

The system aroused great interest among students, employees and local residents, so that the experts from ABB AG - Engineering Solution  - Halle plant were able to explain the system and demonstrate its application during the day.

The organizers of the transformer workshop would like to thank ABB AG for providing and organizing the workshop.