Researchers Develop a Hybrid Inverter That Integrates Distributed Energy Resources

Researchers at Oak Ridge National Laboratory (ORNL) claimed that they had developed a power electronic inverter platform that can easily connect distributed solar panels, electric vehicles (EV), and electric storage systems, with the utility power grid.

According to the researchers at ORNL, the new platform can support smart grids to monitor and control the power flow with better system stability in real-time. Smart grids are systems that function autonomously with real-time monitoring and instant power management for better system stability.

The researchers said that they had installed computing capability in the hybrid inverter platform to support real-time communication and commanding between different control systems and the power electronic-based inverter hardware. They have designed the plug-and-play platform with open-source software to work with any universal control system.

Inverters are used to convert the direct current (DC) generated by power sources to the alternating current (AC) for consumption. According to the researchers, the hybrid inverter platform can serve as the main source of energy conversion between clean but irregular electricity sources like solar and wind. It can match the power supply according to consumer loads while interacting with the larger power grid.

“Every company offering solar power, smart appliances, EVs, and so on, typically has a different control system for their products. What we want to create is a way to integrate all these systems using a common platform and create a smoothly functioning, autonomous, distributed energy system,” said Madhu Chinthavali, Lead Researcher at ORNL’s Electric Energy Systems Integration Group.

The platform started with the VOLTTRON open-source software created by Pacific Northwest National Laboratory. Then, ORNL scientists built a new software agent that can communicate among various control systems down to the power electronics-driven inverter hardware.

“Autonomous systems for the grid can be likened to the evolution of the auto industry,” Chinthavali said. “The shift from manual to automatic transmission enabled a system that requires less effort by operators, particularly in congested areas. Today, that automatic gear system is supporting the move to autonomous vehicles. The hybrid inverter platform is a similar building block for the smart, autonomous grid of the future,” added the lead researcher.

In February 2020, researchers from Tamil Nadu’s Vellore Institute of Technology announced a multi-level inverter for solar water pumps. The seven-level solar inverter comes with five power semi-conductor switches for the operation of a single-phase induction motor pump and can provide a lesser harmonic voltage that reduces filter requirements.