MPPT Charge Controllers

A: A Solar charge controller is an electrical device that regulates battery charging from solar PV panels and protects the battery bank by managing its interface with DC loads. Basically ‘controlling’ the charge to make the Off-Grid solar system operate smoothly.

Why Use a Solar Charge Controller in an Off-Grid Solar System Design?

A: Four key reasons

1. A solar charge controller protects the battery investment. It helps to maintain energy production that operates in the range where a specific battery brand, location, temperature range, application, and/or technology operates best. The solar industry identifies this as ‘optimizing’ battery charging. Preventing overcharging and over discharging of the battery bank will avoid battery damage. This important battery care creates system reliability and maximizes the life of a battery bank. If designed correctly, the right solar charge controller saves customers time and money to avoid costly, inconvenient downtime and unnecessary battery replacements more often than is standard for an application.
2. A solar charge controller prevents reverse current flow to the solar PV panels at night, preventing wasted energy.
3. A solar charge controller typically shows system status information through LED indicators or display screens. This helps to easily monitor system status and when needed, aids in troubleshooting.
4. When advanced features are required for certain applications or in certain rigorous environments, selecting the right solar charge controller can make a significant difference for reliable performance. Features like datalogging, lighting controls, and/or software/applications, allow for more flexibility to suit application specific needs.

Among the range of Photovoltaic (PV) charge controllers, Phocos offers both PWM and MPPT versions.

Phocos MPPT (maximum power point tracker) charge controllers consist of highly efficient DC/DC-converters that actively convert the higher solar panel input voltage to the lower output voltage level (battery voltage) for the battery bank, with only minimal conversion losses. The solar charge controller itself is powered by the battery bank. An MPPT solar controller regulates solar power input and converts it to charge power output compatible for the battery bank. Sensing and control circuitry with an MPPT solar charge controller algorithm continually monitors the battery voltage, environmental conditions and PV solar input to ensure proper battery charging.

When the battery voltage is less than the targeted charging voltage, the MPPT solar charge controller implements maximum power point tracking to maximize all available power from the solar PV array. This is important as PV-voltage at the point of maximum power output varies over irradiation and temperature. In case of shading where multiple local maximum power points occur, Phocos’ MPPT algorithm always tracks the global maximum power point.

The battery supply is powered through connected DC loads through the MPPT solar charge controller’s load switch. Sensing and control circuitry continually monitors the battery voltage, environmental conditions and load current to prevent any situations that would be harmful to either the battery bank or the DC load.

For 20+ years, Phocos has supplied proven, robust PWM and MPPT solar charge controllers.