A service-oriented power quality real-time monitoring system for active distribution network (ADN) based on the browser/server (B/S) schema is designed and realized. The system can monitor the power quality of ADN in the process of integrating distributed generators in real time. The influence of power flow direction change on the power quality level is focused on. A power quality information model based on the IEC 61850 standard is developed. By means of the manufacturing message specification (MMS)

the power quality real-time monitored data on site are uploaded to the master station for parsing

and then stored in the real-time database. The main wiring diagrams of ADN are modeled and drawn by the Silverlight technology. The client side communicates with the server side through Windows communication foundation (WCF) service for retrieving real-time monitored data. By combining the main wiring diagrams

the power quality real-time monitoring for the whole ADN is realized

while the integrated display of graphics and data is realized. The system has successfully been used in an ADN demonstration project in Guangdong Province

and is able to provide effective data for making control strategies and solving power quality problems in AND

which verifies the reliability and practicability of the system. This work is supported by National High Technology Research and Development Program of China (863 Program) (No. 2012AA050212).