PWM vs MPPT

Traditional PWM vs Morningstar’s TrakStar™ MPPT Technology
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Traditional PWM vs Morningstar’s TrakStar™ MPPT Technology
Introduction:
Morningstar MPPT (Maximum Power
Point Tracking) charge controllers’
utilize Morningstar’s own patented,
advanced TrakStar MPPT technology
to harvest the maximum amount of power from the solar array. It is
generally accepted that even the most basic MPPT controllers will
provide an additional 10-15% of charging capability compared to a
standard PWM regulator. In addition this efficiency, there are
several other important differences and advantages between PWM
& MPPT technologies—these basic differences & advantages are
outlined in this whitepaper. This whitepaper will also provide an
explanation on how to properly size solar arrays for each type of
controller.
PWM Charging:
Traditional solar regulators featuring PWM (Pulse Width
Modulation) charging operate by making a connection directly
from the solar array to the battery bank. During bulk charging
when there is a continuous connection from the array to the battery
bank, the array output voltage is ‘pulled down’ to the battery
voltage. The battery voltage adjusts slightly up depending on the
amount of current provided by the array and the size and
characteristics of the battery.
TrakStar MPPT
Morningstar’s
Advanced Control
Algorithm to
Harvest Maximum
Power from a Solar
Array’s Peak Power
Point
• • •
Even the largest and
most efficient controller
can give up crucial
power if it is not
tracking the power
point of the module
correctly.
Speed and logic in the
tracking algorithm will
yield gains that pure
size and efficiency
cannot make on their
own.