Energy Systems

A Technology for the Realization of Increased Stability in Photovoltaic Systems

Identification and instantaneous shutdown of malfunctioning circuits.
Reduction of generation output if trouble does occur.

R&D category Electric Power
Purpose, feature or effect of the R&D Peace of mind, Safety


diagram: Photovoltaic cell module

We have developed the world's first*1 technology able to rapidly detect which circuit of a photovoltaic power system a DC arc*2 is occurring in as a result of connection problems, etc. and to instantaneously shut off the malfunctioning circuit. The ability to identify the malfunctioning area without shutting down the entire system enables rapid recovery, minimizing reductions in generation output and contributing to stable generation.

Technology Point

Identification of circuit in which DC arc is occurring enables reduction of generation output to be minimized

diagram: Technology Point

Monitoring of changes in current and voltage in addition to fluctuations in the current waveform makes it possible not only to detect whether or not a DC arc has occurred, but also to identify which circuit it has occurred in. High-speed detection (detection time: 0.25 seconds or less) allows instantaneous shutdown of the malfunctioning circuit, preventing the problem from spreading. In addition, generation can be continued using the functioning circuits. Recovery time is reduced, minimizing any reduction in generation output.

New technology enables instantaneous shutdown of DC circuits

diagram: ARC SWEEPER®

ARC SWEEPER® is a new circuit interruption technology that dramatically increases the effect of the electromagnetic action of magnets. Irrespective of the direction of the current, this technology makes it possible to accurately and instantaneously shut down a DC circuit.

R&D Award

Wins 2015 R&D 100 Award

No-fuse Switch for HVDC has won a 2015 R&D 100 award from R&D Magazine.

  • photo: No-fuse Switch for HVDC

    No-fuse Switch for HVDC

  • photo: Wins 2015 R&D 100 Award

    Wins 2015 R&D 100 Award

  • *1 As of February 2015 (Mitsubishi Electric study).
  • *2 A high-temperature (several 1000°C) discharge that produces a strong flash, occurring when a circuit with current flowing in it is disconnected.
  • *ARC SWEEPER® is a registered trademark of Mitsubishi Electric Corporation.