In areas where there are many lightning strikes, it is obligatory to automatically stop the wind turbine to ensure safety in the event of a lightning strike.For this reason, lightning strike detectors are also installed on the wind turbines of wind power plants, but conventional lightning strike detectors that install one magnetic field sensor in one unit may erroneously detect lightning strikes in the vicinity. It was one of the factors that lowered the operating rate of wind turbines.On the other hand, the Rogowski coil type, which is currently known as a high-precision detection device, has not been introduced because the coil must be installed all around the base of the wind turbine tower and the cost is high.

　On the other hand, the device developed this time is economical while improving the accuracy of lightning strike detection by attaching three magnetic field sensors to the wind turbine.It is said that the wind turbine that had a lightning strike can be accurately identified from the magnitude and direction of the magnetic field generated by the lightning strike, and it was confirmed in the field test that it works correctly with actual lightning 3 times out of 8 times.The structure is simple and easy to install, and it has the advantage that it can be installed at about one-third to one-tenth the cost of the Rogowski coil type.It can also be installed in wind power plants that are already in operation.

　This device is also ideal for offshore wind power generation.In offshore wind power generation, it takes time to inspect because the equipment is patrolled by ship, but if the lightning strike detection of this device is used, the wind turbine to be inspected can be identified in advance, which leads to reduction of inspection time.

　Shoden Co., Ltd. will start selling the new lightning strike detector, which enables both high accuracy and low price, from June 2018.