Abstract: The increasing complexity of distribution-level source, network, load and storage have been deteriorating voltage imbalance and distortion issues. Therefore, the traditional power theories cannot meet the conversation law and would lead to the limitation of power compensation. A Multi-vector Power Theory (MPT) based reactive current compensation strategy for three-phase non-sinusoidal distribution networks is proposed. The frequency domain decomposition results of voltage and current are employed to establish the basis vector and form the voltage and current vectors, and the geometric product of the two vectors is defined as the multi-vector power. It is proved that the multi-vector power theory meets the conservation law. Then two types of reactive current detection performance improvement strategies aiming at Unity Fundamental Power Factor (UFPF) and Perfect Harmonic Cancellation (PHC) are proposed. Comparing with 7 reactive component detection algorithms under different power theories developed by different working conditions, 5 algorithms with better results are selected to build reactive power compensation simulation models, and to design physical experiments to verify the algorithms. The results show that the UFPF on MPT achieves the lowest apparent power flowing into the system, and the PHC on MPT has the best comprehensive compensation for all non-active power, harmonics and unbalanced components.