System Components & Design

String inverter

A central inverter that converts the combined DC output of one or more module strings to AC; cost-effective but limited

Microinverter

A small inverter mounted at each module that converts DC to AC at the module level, improving performance under shading

DC power optimizer

A module-level DC-DC device that performs MPPT per module and sends optimized DC to a central string inverter.

Charge controller purpose

Regulates current and voltage from the array to the battery, preventing overcharge and (in many units) over-discharge.

PWM vs. MPPT charge controllers

PWM controllers pull array voltage down to battery voltage (simple, lower cost); MPPT controllers convert excess array v