Electrical machines-based multi-disturbance device for testing distribution grid technologies

The growth of distributed energy resources in power systems, mainly converter-coupled generators, has forced the evolution of grid codes, increasing the requirements to be fulfilled by the generators before their connection to the mains. Solving this problem is crucial to guarantee the reliability and stability of the power system. Current standards force the generators to remain connected when facing voltage and/or frequency disturbances and, in some advanced grid codes, also when the generators are facing transient phase jumps produced as a consequence of those disturbances. If considering that the increment of the distributed generation is mainly done at a distribution level, it is unrealistic to consider voltage and frequency events as decoupled phenomena in the testing and certification procedures, as it is currently done. The testing device proposed in this paper is able to reproduce voltage, frequency and phase jumps disturbances of a controlled value simultaneously, being able to reproduce the real grid behavior reliably. Its design is based on standard components with a simple control system, which makes it easily replicable and scalable up to the power of the device to be tested. Therefore, the proposed device is an interesting commercially competitive testing equipment suitable for certification.