Modular and Scalable Solar Microinverter

Executive Summary

Induction motors are used in a myriad of applications. Often, however, they are oversized and draw high starting currents which typically incurs additional electricity charges. For pumping applications, this can also lead to excess wear of the pump and piping system. While a variable speed drive (VSD) may alleviate this problem, VSD’s are expensive to install and may be uneconomical. Researchers at Michigan State University have recently developed a new solar microinverter that can soft start induction motors, thus relieving them of peak energy use during startup. The system saves energy, high current draw overcharges and can be used to put renewable solar energy back to the grid during operation.

Description of the Technology

The technology consists of a solar panel, microinverter, and control system. Software includes an advanced PLL and fault detection system. The hardware can be directly attached to existing equipment with minimal wiring and installation. A lab scale unit has been developed and testing to show proof of concept and a larger field unit deployed in an agricultural irrigation pump, where a field trial is currently in progress in a Michigan apple orchard.

Benefits