Mouser - White Papers

Mouser Electronics White Paper Home Battery Energy Storage System Design A home battery energy storage system comprises several key components and interconnects for analog, digital, and power electronics (Figure 3). There are many possible configurations of all BESS components, but fundamental requirements exist for interconnection, operation, and tying to the grid, if applicable. The central components of a BESS are the gateway and inverter. At a high level, these devices act as the bridge between the grid, home AC mains, and the BESS. The gateway includes electronics that sense the grid status (if tied to the grid) and can supply energy back to the grid through the utility meter and house service. The inverter is a device responsible for converting the DC energy from the BESS to AC energy usable by the grid and the AC loads of the home. The BESS, at minimum, includes battery energy storage and the electronics that monitor and control the electrical energy to and from the battery storage, known as the battery management system (BMS). In some configurations, the gateway may also direct AC energy from the grid to the BESS. This configuration also requires battery-charging circuitry that converts the AC energy from the grid to DC energy, which is then controlled and adequately conditioned to charge the battery energy storage. It is important to have a battery-charging system that is specifically designed for the type of battery used in the BESS to prevent damage to the batteries, optimize battery life, and ensure efficient charging of the batteries. To address these challenges, designers must utilize energy storage solutions that balance enhanced power throughout with effective thermal management. Suppose solar, wind, or other renewables are used also to provide energy to the system. In that case, these energy sources may be directly connected to the BESS or through the gateway. If additional energy sources are available and connected through the gateway, they may require energy-conversion electronics different from the battery-charging circuitry and inverter used in the gateway. These systems also require additional interconnects, including a transfer switch if connected to the home service (such as how a backup generator is connected to a home). Another example is the energy conversion electronics needed to convert three-phase (typical wind generator configuration) from a wind turbine to the two-phase or single-phase AC used in residential or DC to energize a BESS. A solar power installation may require additional conversion electronics, such as an inverter that converts the DC from solar to either AC for the home or a DC-DC converter for energizing the BESS. In some cases, the inverter used to convert the DC provided by the BESS may also be used for solar energy conversion. Figure 3: Diagram of a residential BESS, optional solar connection, and grid-tie. (Source: Mouser Electronics)

• Cover