【Technical Overview】
By knowing more and more renewable energy will be merged into the grids in the future, the problems are emerging gradually when fault happens within power flow and power transfer. Also, since the technologies of power supervision and geospatial information are not integrated sufficiently by local companies, the application of renewable energy information becomes less flexible. For this reason, NARI has developed the Domestic Distribution Network Management System containing renewable energy, which integrates the Supervisory Control and Data Acquisition (SCADA) System and the Geospatial Information System (GIS).
The instability and unpredictability of renewable energy lead to voltage fluctuation or three-phase unbalance. Due to these disadvantages, a distribution feeder switch operating sequence strategy platform is developed by NARI. During every switching, the interconnection switch would be opened prior to the normal-closed breakers to avoid power outage. Besides, the three-phase loads and the capacity of renewable energies can be calculated. This allows the dispatchers of power company to practice the procedure of switch status adjustment. Also, the strategy proposed by the platform can decrease the maximum changing rate of three-phase load and ensure the reliability of switch operation and dispatch.
There are many nodes in the primary main and branch lines of complicated distribution systems. Therefore, lots of measuring equipment should be built to obtain precise information from each node. Not only is the cost of building equipment high, but it is difficult to deal with the processing of massive data. However, if the information is not enough, it will be hard to monitor the voltage raise caused by the high penetrating renewable energy. This will further influence the quality of power utilization. For this reason, NARI has developed the technology for state estimation, which makes it possible to estimate the condition of power supply for the primary main and branch lines of distribution systems. The estimated results can also be compared with the measured values, and the information can further be shown on the Geospatial Information System (GIS). This can assist the dispatchers to monitor the fluctuation of feeders caused by distributed generation and inspect whether the supervisory device is operating normally.
Furthermore, NARI applied graphical structure and bi-directional tracking technique to track the geometric data in geospatial database, such that the length of each line based on the coordinate information at each node can be gained. As well, the data in the distribution feeder information database can be referred to and cross-validated, and the data references in the database is therefore established. With the connectivity tracking technique, the operation data of Fault Current Indicator (FCI) can be analyzed to help minimize the fault area for further review.

Figure 1. Domestic Distribution Network Management System


Figure 2.Switch Operation Sequence Strategy Platform


Figure 3.User Interface and Platform for State Estimation Strategies


Figure 4.Application Program for Shrinking Fault Area of Distribution Systems

【Project Planning/Technological Application】
NARI has collaborated with domestic industries concerning electrical and information engineering to develop the cross field technologies of feeder dispatch with high penetration of renewable energy and distribution feeder information applications. Also, the Domestic Distribution Network Management System has run online at the Distribution Feeder Dispatch Center of Taipower Yunlin Branch in April 2019. The performance of this system is nearly competitive with foreign products. Only if the data are extracted from distribution feeder information management system shall the one-line diagram and renewable energy information be constructed automatically. It can save time for the file conversion of distribution feeder information, and effectively manage more than 300 feeders and renewable energy sources whose total capacity is more than 700 MW in the distribution system of Yunlin County. The associated research achievements were claimed in two patents, i.e. “Method of Transfer Supply Containing Green Energy for Distribution Feeder” and “Divisional Section Transfer Power Restoration Strategy of Distribution Feeder”. Moreover, the iDNMS  technology based on the above achievements won the Platinum Awards twice in Taiwan Innotech Expo (TIE) in 2020 and 2022, as well as the R&D 100 Awards in 2021, which is considered as one of the highest ranked awards in technology industries. In addition, the research team also won the Outstanding Contribution Award of Functionary in 2021, which is the highest honor in government agencies.


Figure 5.R&D 100 Awards in 2021


Figure 6.President Tsai Granted Outstanding Contribution Award of Functionary to Research Team

【Future Planning】
NARI is planning to promote the Domestic Distribution Network Management System to all Taipower’s distribution branches, so as to aid the management of electric grids with renewable energy of high penetration and further explore opportunities of novel industries. NARI will continue developing techniques in the domains of three-phase power grid configuration, state estimation, dynamic protection coordination, dynamic visualization of geospatial information containing renewable energy and so on. It is hoped that hope the works of this project can improve competitiveness and create novel applications in overseas markets for domestic associated industries.

【Contact Information】
Name： Jheng-lun Jiang
Tel：03-4711400 Ext. 6363
E-mail：Jhenglun@nari.org.tw