Toshiba Mitsubishi-Electric Industrial Systems Corp (TMEIC) announced that it has added a function to reduce the output of a solar power plant in real time in accordance with output control orders from a power company to its products.
As a result, its products can now deal with output restrictions in the service areas of Kyushu Electric Power Co Inc (Kyuden), Shikoku Electric Power Co Inc (Yonden) and The Okinawa Electric Power Co Inc.
Kyuden established a real-time output control technology through a verification test (next-generation bidirectional communication output control emergent verification project) in fiscal 2015.
In the project, Kyuden conducted verification separately for (1) solar power plants connected to 66kV and higher-output-voltage extra-high voltage power transmission lines and (2) plants connected to less-than-66kV high-voltage power lines. But TMEIC was the only PV inverter manufacturer that had participated in the verification of both types.
TMEIC established a control technology supporting both 66kV-and-higher and less-than-66kV projects by integrating knowledge accumulated through verification and system technologies developed by the company, it said.
TMEIC's control system can be applied not only to Yonden, which has already started output restriction, but also to Yonden and The Okinawa Electric Power, which have started to prepare for output restriction. And TMEIC plans to make the system support the output restrictions of other companies.
Specifically, the control system supports solar power plants connected to 66kV and higher-output-voltage power lines by adding the output control function to the "Main Site Controller (MSC)." The MSC is a host system that optimally controls grid connection output through the centralized control of all the PV inverters of a power plant.
It controls the total output of all the PV inverters. Therefore, when solar irradiation in the site is uneven within a site, it reduces power generation loss and maximizes the amount of power generation, according to TMEIC. Such technologies can be effectively applied to output restriction, the company said.