Overlaying control mechanism for solar PV inverters in the LV distribution network

- Bridges the gap between research and real-life implementation.
- A decentralized control for overvoltage mitigation is proposed.
- The solution is hardware independent, scalable, thus it is a model-free control.
- Multiple power quality problems can be mitigated using hierarchical architecture.
- Real-life implementation challenges are identified and solved.

Increasing penetration of distributed renewable energy sources in LV grid leads to a number of power quality challenges. Meanwhile, changes in recent renewable energy-related grid codes foresee the massive introduction of remotely controllable inverters in the LV grid. In this paper, the future grid scenario is taken under consideration, thus proposing a solution for overvoltage problem while taking advantage of such controllable inverters. The paper discusses a novel approach to mitigate overvoltage problem by integrating the concept of P-V droop control into a cyber-physical paradigm. The proposed approach introduces a parameter, referred as virtual maximum power point that enables the proposed solution to mitigate overvoltage problem only by using local measurements. Above all, the proposed approach prevents any new hardware-related changes in the inverters. This paper simulates the proposed approach using a co-simulation model. However, to speed up the field implementation of the proposed approach, laboratory experiments were conducted and the solutions for the challenges in real-life implementation, including ICT-related challenges, are developed. Lastly, this paper discusses about the outcomes of the proposed approach in the light of both the theory and practical. In addition to the proposed overvoltage mitigation solution, the possibilities of using the controllable inverters for additional network services are also discussed.