Specifications
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A maximum point power tracking system would be able to take the characteristics of the
example PV array and determine its‟ maximum point and use that for an optimized
charging system as seen below.
Figure 14 - MPPT Benefit Graph
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The maximum point power tracking system can take what inputs are available to it and
combine them in a way to where the most efficient use of energy is able to pass through
it. As it is seen above with the blue and green lines of the graph where the blue line
shows the voltage and current available to the maximum point power tracking system.
After the maximum point power tracking system is able to take these inputs it is able to
develop the green line which is a combination of the input voltages and currents and
from that green line determine where the most efficient use of power is for the charging
battery.
4.1.4 Power Inverters
There are two widely used types of power inverters today; the modified sine wave
inverter and the pure sine wave inverter. Both types operate by performing two basic
steps. The first part of the power conversion process is to transform the direct current
coming from the battery into an alternating current. Nowadays this is typically done with
transistors or logic devices, but the first power inverters were made with
electromagnets. By choosing the correct parts here, the frequency and shape of the
output can be chosen. The second part of the conversion is to step the voltage up or
down using transformers. In this case, the power inverter will be converting 12 VDC to
120 VAC at 60 hertz, which is the standard form provided by the electricity grid here in
the United States. When this device is implemented in Japan, the power inverter will