January 18, 2019
Sumitomo Electric Industries, Ltd.
This press release was originally published in Japanese on December 25, 2018.

Sumitomo Electric Develops AI-based Failure Detection
System for Maximizing Output of Photovoltaic Power Plants
Sumitomo Electric Industries, Ltd. has developed a data storage and analysis
system that quickly detects reduction of photovoltaic (PV) power output by using
artificial intelligence (AI) working in conjunction with a string monitoring system
for solar power generation plants. The system is available for sales from April 2019.
Most solar power generation plants currently being built in Japan are expected to operate
for more than 20 years after installation. To maintain consistent output power for a long
period of time, it is critical to quickly detect and restore failures that may cause reductions
in generation output. To this end, a monitoring system to detect such failures is installedin each plant.
Conventional monitoring systems use threshold value, or critical value, to determine thereduction in power output. For instance, once the output underperforms the threshold,the system determines it as a failure and alerts the operator of the solar power generation
plant. However, output power varies according to various factors such as season, timeof day, installation area or surrounding environment, and therefore solely using thresholdvalue lowers reliability, not to mention the need for additional human analysis andsubsequent decision making, both of which require experience and greater effort.
Against this backdrop, Sumitomo Electric has developed a string monitoring system thatuses AI to detect failures from the measured string power value and report the cause
according to predefined emergency levels. In detecting a reduction in power, the system
identifies its cause (such as failure of fuses or breakers, shadows from trees and grassor deterioration of solar panels), and reports the cause according to a predefined
emergency level. Detection of failure is made on each string, theminimum unit of solar power generation system and the failed
area is displayed on the plant’s map in different colors classified

1/4

according to emergency level, thus enabling easy identification of the failure area andthe provision of precise instructions to workers.
Our monitoring system uses power line communication (PLC)*1 technology, which uses
existing power lines for data communication, thus eliminating the need for additional
installation of a communication line, enabling easy installation to existing plants alreadyin operation. By using the recently developed failure detection and reporting system,
failures are promptly and precisely detected and reported at an early stage, reducing
operating costs of the solar power plant and loss of power generation.
The system is available for sales from April 2019. We look forward to your positive
consideration for possible introduction of the system.

Features1. Advanced string current data analysis using AI classifies the cause of the failure intoa maximum of seven categories and reports it according to a predefined emergency
level.

2/4

2. Daily reports can be sent to designated e-mail addresses. In addition to any failures
measured on the day, other information such as power generation output is visuallydisplayed.

3/4

3. String with failure occurring is overlaid on the power plant map. (Optional functions)* The display layout shown here is still under development and may vary in the system
available next April.

*1 Power Line Communication (PLC) is a technology to use existing power lines for datacommunication. Our product has adopted a low frequency PLC technique using 450 kHzand lower frequency, superimposing data measured from string current on DC lines.
■ Reference
Sumitomo Electric's Website
https://sumitomoelectric.com/4/4