Switchgear testing

The power grid operator needs to be able to interconnect and disconnect segments of the grid.

In case of a failure in one segment—like a lightning strike, short circuit due to component breakdown, etc.—the rest of the grid has to be protected by disconnecting the segment with the failure.

High currents (up to hundreds of kA) have to be interrupted, while high voltages (up to several hundreds of kV) are present. Switchgear testing is one of the very demanding applications, requiring specific hardware and software to produce accurate and reliable test results. The hardware challenges include isolation, amplifier drift, noise, electromagnetic immunity and battery operation. The software challenges include data integrity, repeatability and productivity.

Genesis HighSpeed from HBM is well known in the measurement marketplace, and has been for nearly 60 years.

• More than 15 years experience in High Power and High Voltage applications
• Committed to invest in the development of solutions for this market
• Worldwide coverage with subsidiaries and representatives

The Solution

The application requires data acquisition system, fiber optic isolated digitizer, test sequencer and analysis software. A complete system with all needed components provided by a single solution provider has an important advantage - system responsibility is covered by one single supplier!

• Standard hardware and software with application specific extensions
• Fully compliant with international standards and recommendations of the High Power/High Voltage community
• Proven hardware design to withstand severe electromagnetic environmental conditions
• Proven software design and algorithms suggested by relevant standards and recommendations

Cost of Ownership

In the lifetime of a measurement solution, the purchase price is only one factor. The longer a system should be in operation, the more important other factors become. Hardware maintenance is one element, but in today’s fast changing information and communication environment, software becomes more and more of an issue.

Using standard hardware with application specific extensions like the fiber optic isolated digitizer provide the benefit of a worldwide installed base.

Standard software with application specific extensions have a big advantage over fully-customized software solutions — the base software is maintained for a large installed base and the cost is split between many users.

Customization

Sometimes a user wishes to have changes made to a commercial software package. The Perception CSI option allows programmers to adapt the existing Perception to specific customer needs. The advantage for the user is the combination of:

• Regular updates of the base software and the provided options to adjust to changes in the operating system, address known issues and implement new features
• Only customization required, not full application solution has to be programmed
• User can focus on his real tasks, rather then spending time on software maintenance

Isolation

The different voltage levels for HV (high voltage), MV (medium voltage) and LV (low voltage) require different isolation solutions. A HV test is preferably done with a pure battery-powered and fiber optic isolated digitizer to get the best possible signal quality and protection for personnel and equipment.

On the other side, an LV test is preferably done with stand-alone isolation amplifiers to keep the cost per channel down. The resulting conversion from analog-to-digital and from digital-to-analog (in the stand-alone isolation amplifier) followed by the analog-to-digital conversion (in the DAQ input channel) will result in less accuracy. This and the lower isolation are often accepted in favor of the cost per channel. Features include:

• Fully battery operated, fiber optic isolated digitizer 6600 HV
• Fiber optic isolated digitizer 6600 MV with isolated power supply and small battery

Timing

Switchgear testing requires a device for accurate sequence and timing control. The BE3200 is a high speed test sequencer for switchgear applications. The timing pattern of the BE3200 can be synchronized to the mains generator, the external mains or derived from an internal timer. All outputs and inputs of the BE3200 are fiber optically isolated.

Case Study

World class power testing in ABB's High Power Laboratory: Superfast sampling with the Genesis HighSpeed measuring system.

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