Influence of the grid parameters during under voltage ride through (UVRT) testing

Forschung im Ingenieurwesen ◽

10.1007/s10010-021-00446-1 ◽

2021 ◽

Author(s):

Anica Frehn ◽

Rayk Grune ◽

Heiko Röttgers ◽

Antonello Monti

Keyword(s):

Wind Turbine ◽

Test Bench ◽

Voltage Divider ◽

Grid Impedance ◽

Virtual Impedance

AbstractUnder-voltage ride through (UVRT) tests can be carried out on system test benches, most of them are equipped with a converter based grid simulator. This paper describes the control of the artificial grid impedance at the 4 MW test bench at CWD. Validation measurements with the commercial wind turbine E‑115 E2 show that the virtual impedance specification is sufficient to perform UVRT tests with different grid parameters. Comparative measurements between the voltage divider based FRT Container and the grid simulator with deliberately different grid parameters show a different behavior of the research wind turbine FVA nacelle. Therefore, it is recommended to perform UVRT tests on the test bench with predefined grid parameters.

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First comparison of the electrical properties of two grid emulators for UVRT test against field measurement

Forschung im Ingenieurwesen ◽

10.1007/s10010-021-00476-9 ◽

2021 ◽

Author(s):

Anica Frehn ◽

Soroush Azarian ◽

Gesa Quistorf ◽

Stephan Adloff ◽

Fritz Santjer ◽

...

Keyword(s):

Wind Turbine ◽

Field Measurement ◽

Test Bench ◽

Voltage Divider ◽

System Level ◽

Hardware In The Loop ◽

Extra High Voltage ◽

First Time ◽

State Of Art ◽

Technical Rules

AbstractThe technical rules for connecting turbines to the medium, high or extra-high voltage grid in Germany require the certification of the UVRT characteristics of wind turbines. The state-of-art voltage divider-based test equipment, also named UVRT-Container, is well equipped for executing UVRT tests in field. To conduct the UVRT in field the full wind turbine should be already installed. A second option to perform UVRT tests are system level test benches. They enable the testing of the nacelle. The components that are not actually present, such as the turbine tower or the blades, are emulated via a mechanical hardware in the loop (HiL) system. In this work, for the first time, the performance of two different grid simulators installed at the DyNaLab at Fraunhofer IWES and at the CWD at RWTH Aachen University is compared with a field measurement of the same type of wind turbine. Thus, not only a system test bench measurement is compared to a field measurement. Rather, two system test benches with individual technical approaches are additionally compared with each other. The focus of this work is to investigate the characteristics of the grid simulators within the steady-state range of the UVRT tests to replicate identical fault shapes on the test benches and in the field.

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