Distribution System Reliability Assessment Considering Voltage Deviation and Sag from Consumer Side

Power quality problems from consumer side may cause similar negative influence on power consumers like outages and faults in distribution system. However, traditional reliability assessment in distribution system is usually conducted from system side, while neglecting the negative impact on reliability level from power quality problems, such as voltage deviation (usually low voltage problem) and voltage sags. To overcome the shortcomings mentioned above, some new metrics for distribution reliability assessment considering the influence from power quality problems are presented in this paper. Those metrics considering influence from low voltage problem and voltage sags, can be defined as "equivalent reliability metrics". In addition, a modified reliability assessment method for distribution system considering power quality problems is proposed in this paper, in order to calculated the proposed new metrics considering power quality from consumer-side. A case study is applied to illustrate the effectiveness and efficiency of the proposed metrics and method.