Adjustable VAR Control Supports Renewable Integration

November 23, 2014 by Jeff Shepard

The GridStrong™ offering of distribution grid control and power quality improvement systems from ZBB Energy Corporation enables utility customers and grid operators to improve power quality in areas with a high-penetration of solar energy or plug-in hybrid vehicles, as well as areas at the "edge-of-the-grid" where performance is challenged. GridStrong also enables conservation voltage reduction (CVR) and improved peak demand management. The ZBB GridStrong is an adjustable VAR (volt-ampere reactive) generator that is vital to providing high quality power in the grid.

Reactive power is key to regulating the voltage in the network. If voltage is too low or too high, equipment in the grid or at the user can malfunction and possibly incur damage. Introduction of intermittency of supply, such as solar energy, or demand, like occurs with plug-in hybrids, can cause the grid voltage to go out of compliance. Additionally, power quality is also a challenge in remote areas of the grid due to long transmission lines, as well as in congested urban areas with heavily loaded circuits. GridStrong can generate inductive (importing) or capacitive (exporting) VARs to ensure the voltage through the grid stays in the acceptable range, even with heavy intermittency.

The ability to perform both inductance and capacitance correction differentiates GridStrong from other VAR generators in the market. Grid operators are also looking for ways to be able to reduce the voltage in the grid without falling outside of voltage limits as this can help save a significant amount of cost. GridStrong can also enable conservation voltage reduction by virtue of its ability to "optimize" VARs. The GridStrong product is power pole mountable and enables adjustment of response time, dead band and voltage control bands, has local user interface, and can also be monitored and controlled remotely.

"GridStrong is the latest addition to ZBB's portfolio of energy management and power quality solutions that enable a dramatic increase in implementation of renewable energy generation, whether into the grid or behind the meter," said Eric Apfelbach, Chief Executive Officer of ZBB Energy. "The drive to increase the penetration of distributed PV, as well as the increase in plug-in hybrid vehicles can significantly degrade the power quality in a community. The ZBB GridStrong product enables this increase in intermittent energy supply and demand, while ensuring the quality of the power meets the requirements."