Murata developing 1kW mini-inverter for solar power generation

Murata has developed a 1kW mini-inverter concept for solar power generation. Compared to the string inverters (power conditioners)^*1 commonly used today for solar power generation, the new mini-inverter features a compact size, a long life, and high generating capacity and also makes it possible to reduce overall system costs as a result of simplified installation and maintenance.

The string inverters generally used for solar power generation have a number of issues, including complex string designs and the need for complicated wiring installation; low environmental tolerance, including susceptibility to effects from shadows; reduction or cessation of power generation; and short lifespans. Micro-inverters, which address these issues, are becoming increasingly common in the United States, but they also have a number of issues, including high cost, low conversion efficiency, and inadequate compliance with grid-connection regulations.^*2
In response, Murata developed a mini-inverter that combines the advantages of both string inverters and micro-inverters. By adopting a compact, thin and lightweight design that uses our unique high-efficiency multi-level circuit technology^*3 as well as a sealed structure, the mini-inverters require a smaller space than general string inverters, thus expanding installation flexibility. Furthermore, the new mini-inverters ensure an output of 1kW despite their small size, facilitating optimal distributed system structures, management on a detailed level, and responses to installation and failures. They also achieve high efficiency and high generating capacity, an issue for micro-inverters. Mini-inverters reduce overall photovoltaic system costs, including related equipment and materials, installation, and maintenance, contributing to solutions to global environmental issues.

• Long life: The design life is 20 years, the same as photovoltaic panels, substantially reducing maintenance costs.
• High efficiency: High conversion efficiency compared to micro-inverters.
• High generating capacity: The mini-inverters avoid reductions in output as a result of effects from shadows and angle and reduce effects from panel failures.
• Easy installation: Installation on the back of or near panels is possible, eliminating the need for long-distance DC wiring, junction boxes, and step-up units.
• Monitoring functions: Monitoring is possible on a detailed level, making it easy to identify failures of panels and other equipment.
• Environmental resistance: The sealed structure, compact and waterproof design, and wide operating temperature range expand the scope of possible installation locations.
• Wireless communications: Equipped with 920 MHz communications functions and links with HEMS and BEMS are possible. Communications wiring is not needed.
  
  

• Photovoltaic panels integrated with building materials (wall and roof materials)
• Solar power generation where the angle is complex or there are effects from shadows
• Mega solar systems without detailed monitoring and single points of failure^*4
• Distributed and compact photovoltaic panels installed on carports, verandas, etc.
• Photovoltaic kits
  
  

* This is a development product, and the electric characteristics may change at the time of mass production.

• Input voltage: 80 V to 250 V
• Output voltage 200 V (1P3W)
• Rated power: 1kW
• Efficiency: 97%
• Waterproof rating: IP66
• Communications means: 920 MHz
  
  

* This is a development product, and the external size may change by the time of mass production.
450 × 160 × 50 mm

Mass production will start in 2017.

*1. Power conditioner: A general term for string inverters
*2. Grid-connection regulations: Detailed indication of the technical requirements between electric power businesses and generating equipment installers to promote efficient discussions concerning grid connections. Many distributed renewable energy generation facilities, including solar, wind, and hydroelectric power, are connected to the distribution grids of electric power businesses, and it is necessary for grid-connection inverters to satisfy the regulatory requirements.
*3. Multi-level circuit technology: A string inverter circuit technique.
*4. Single point of failure: A point that, if it stops working, will stop the entire system from working.

Murata Manufacturing Co., Ltd. is a worldwide leader in the design, manufacture and sale of ceramic-based passive electronic components & solutions, communication modules and power supply modules. Murata is committed to the development of advanced electronic materials and leading edge, multi-functional, high-density modules. The company has employees and manufacturing facilities throughout the world. For more information, visit Murata's website at www.murata.com