Optimization is a technique for shade and mismatch mitigation using simple sensing and solar module output control by module level power electronics (MLPE). Optimizers are the simplest of all module-based electronic solutions in both part count and the way that they ensure the maximum amount of power from a shaded module. Although there are other forms of mismatch, which is defined as the reduction of solar module output caused by shading or other environmental factors, shading is the most talked about.
When a solar module is shaded, either partially or fully, bypass diodes redirect the current around the shaded cells in the module. These bypass diodes reduce the effects of shading and are integrated into almost all modern PV modules. Here is an article that discusses shading and other kinds of mismatch in more detail.
Although bypass diodes somewhat lessen the effects of shading, the Tigo optimizer recovers more lost energy, thereby increasing energy production. The optimizer calculates the maximum power point of its connected module by using patented software algorithms. The optimizer "senses" a reduction in current caused by some shading. It adjusts this module's current to reflect the correct “virtual” resistance for each module, thus preventing the lower producing module from dragging down the production of the higher producing modules in the string.
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