Power relay boasts bidirectional switching capability

It is capable of bi-directional switching allowing it to replace several conventional relays. The G9KB relay has been designed to address the key challenges presented by energy storage systems and other bi-directional systems that require energy consumption and energy charging to help achieve carbon neutrality and strengthen disaster resilience.

The power relay is in stock at authorised distributor Anglia Components.

The high-capacity requirement of energy storage systems has led to increases in installation footprints due to the large size of equipment and the shortened life of printed circuit boards and other components which occur as a result of the substantial heat generated inside the equipment which subsequently requires passive and/or active cooling systems.

OMRON's power relay G9KB can achieve bidirectional switching with a single unit while retaining high-voltage and high-capacity switching capability (600 VDC, 50 A for standard model and 800 VDC, 100 A for option E model).

The G9KB relay allows designers reduce the size and weight of energy storage systems and helps lower heat generation inside the equipment solving installation restrictions and extending the service life of clean energy-related equipment.

OMRON's research demonstrated by replacing four conventional power relays in a 600V VDC charging/discharging system with a single G9KB relay reduced the PCB mounting area required by 75% enabling equipment to be smaller and lighter (reduced footprint). At the same time, the reduced initial contact resistance of 5 mΩ or less, up to 47.5% (at 20A energization) lower than the four conventional relays, enabled lower heat generation and a more cost-effective overall solution due to higher charging efficiency and longer service life with less cooling requirements.

As devices related to solar power generation and energy storage systems continue to increase in voltage and capacity, the importance of a safe disconnection function is becoming increasingly important. In accordance with this, stringent standard requirements may be requested for PCB relays as well.

Although OMRON's G9KB is a PCB relay, it has obtained UL 60947-4-1 and IEC 61810-10 standards with the same structure, which are stringent requirements for switching devices such as contactors, this means it can be reliably applied to safe disconnection applications for energy storage systems.

Arc interruption technology

Generally, when turning DC current on or off, an arc occurs between the contacts of a switching device. In bidirectional switching applications such as energy storage systems, it is necessary to interrupt the arc and prevent welding of the contacts even if the direction of the current is reversed. However, it is not easy to design a relay that can safely cut off current in both directions with the same structure, because the direction and characteristics of the arc also change when the direction of current flow changes. The G9KB relay has arc control technology built in using permanent magnets and three-dimensional arc analysis technology (CAE technology) to realize a structure that is not affected by the direction of the current in an air-break type. OMRON's highly reproducible CAE technology has been established through industry-academia collaboration, thereby allowing them to achieve both miniaturization and high capacity with the G9KB relays (see picture).