Voltage rise with Zero Grid Reactive Power (a) load varies at 0.4 s to 0.6 s, and switched off at 0.6 s to 0.9 s, grid current increases. (b) Reduction in the load power between 0.4 s to 0.9 s (c) Increase in power to the grid due to reduction in the load between 0.6 s to 0.9 s. (d) Reactive power during unity power factor mode of the STATCOM.
To mitigate the voltage rise issue at the sending end, assuming Z and system side voltage \ (\dot {V}_ {T}\) constant, two ways can be seen from (3): ① Reduce active power injection; ② Apply negative reactive power injection.
The paper discusses the modelling requirements for PV system integration studies, as well as the possible techniques for voltage rise mitigation at low voltage (LV) grids for increasing PV penetration. Potential solutions are listed and preliminary results are presented. Solar energy is the most important natural energy source to the world.
Reference 19 established that voltage rise depends on the value of line resistance and real power injection. With the advent of over generation of power from RDG, there may be a need to curtail some RDG real power or absorb reactive power by RDG inverters to eliminate the voltage rise.
It can be observed that without any reactive power control, the voltage remains within the allowed range since the load consumes all the active power generated by the PV system. Therefore, the risk of voltage rise is extremely low. The Q (V) control technique shows minimal voltage decrease.
Another study proposes a reactive power control technique to address voltage rise on low voltage distribution networks using PV active power injection PF (P) and network voltage (Q (V)). The weight assigned to each technique varies based on the level of PV active power injection.