Voltage Regulation Planning for Distribution Networks Using Multi-Scenario Three-Phase Optimal Power Flow

Active distribution networks must operate properly for different scenarios of load levels and distributed generation. An important operational requirement is to maintain the voltage profile within standard operating limits. To do this, this paper proposed a Multi-Scenario Three-Phase Optimal Power Flow (MTOPF) that plans the voltage regulation of unbalance and active distribution networks considering typical scenarios of operation. This MTOPF finds viable operation points by the optimal adjustments of voltage regulator taps and distribution transformer taps. The differentiating characteristic of this formulation is that in addition to the traditional tuning of voltage regulator taps of an active network applied for just one scenario of load and generation, it also performs the optimal adjustment of distribution transformer taps, which, once fixed, is able to meet the voltage limits of diverse operating situations. The optimization problem was solved by the primal-dual interior-point method and the formulation was tested using the IEEE 123-bus system.

Research on the Coordination Control between STATCOM and VQC in Substation Based on the Identification of System State

For traditional voltage and reactive power control (VQC) of substation will cause frequent adjustment of transformer taps and switching of capacitor banks, which exerts a certain impact on system voltage, the static synchronous compensator (STATCOM) is supposed to be installed in the substation to improve the effect of VQC. A coordination control strategy between STATCOM and VQC in substation based on the identification of system state is proposed in this paper to coordinate the operation between on-load tap changers (OLTC), capacitors and STATCOM. In addition, we have a research on the application effect of this strategy with BPA. The simulation results show that STATCOM plays an important role in improving the substation performance in both steady state and transient state and it can effectively reduce the frequency of tap changing and capacitor switching. Besides, the system will perform better if both of the main transformers are equipped with STATCOM than only one is configured.

Research on Reactive Power and Voltage Optimization of Regional Distribution Network

The high-medium voltage level distribution networks have their own characters. Because of the radiation characteristic of the network, this paper looks on the network as the combination of some small optimization unit. The paper simplifies the resolution of the reactive power optimization by the way of alternatively solving the adjusting transformer taps and switching capacity banks. At the same time, considering the practical operation request, the paper evaluates the regulation effect and improves the practicability of the software.