Specifications
iii
List of Figures
Figure 1 - Block Diagram of Overall System Layout ....................................................................................................... 2
Figure 2 - Typical Construction of a Lead Acid Battery ................................................................................................ 10
Figure 3 - Comparison between the Construction of Wet Cell, AGM, and Gel Cell Lead Acid Batteries ...................... 11
Figure 4 - I-V and P-V Curve of a Typical 75W PV Panel .............................................................................................. 12
Figure 5 - I-V Curve of a PV Panel at Various Sunlight Levels ...................................................................................... 13
Figure 6 – Lead Acid Battery Charger Circuit ............................................................................................................... 14
Figure 7 – Lead Acid Battery Charging Stages ............................................................................................................. 15
Figure 8 – Nickel-Metal Hydride Battery Charger Circuit ............................................................................................. 16
Figure 9 - Charging Characteristics of a Nickel-Metal Hydride Battery ....................................................................... 17
Figure 10 - Lithium Ion Battery Charging Circuit.......................................................................................................... 18
Figure 11 – Charging States of Lithium Ion Battery ..................................................................................................... 19
Figure 12 - Charging Stages ......................................................................................................................................... 22
Figure 13 - MPPT Characteristic Graph ........................................................................................................................ 23
Figure 14 - MPPT Benefit Graph .................................................................................................................................. 24
Figure 15 - Modified Sine wave inverter signal vs. pure sine wave inverter signal ...................................................... 25
Figure 16 - Verical Axix Wind Turbine .......................................................................................................................... 27
Figure 17 - Horizontal Axis Wind Turbine .................................................................................................................... 27
Figure 18 – HAWT Wind Direction ............................................................................................................................... 28
Figure 19 – Wind Intensity Map................................................................................................................................... 29
Figure 20 - Global Sun Exposure Map .......................................................................................................................... 29
Figure 21 – Charging System form Solar Panel ............................................................................................................ 31
Figure 22 - Thin PV Cell Array Flexibility ...................................................................................................................... 31
Figure 23 - Current vs. Voltage at Different Temperatures ......................................................................................... 32
Figure 24 - Thin Film Array Panel Layers ...................................................................................................................... 33
Figure 25 - Battery Terminal Voltage vs. Percentage of Battery Charge Remaining ................................................... 34
Figure 26 - Comparison between Placing a Current Sensor on the High Voltage Side of a Load vs. the Low Side ...... 35
Figure 27 - SparkFun LCD Display ................................................................................................................................ 35
Figure 28 - Backlight Brightness for LCD Screen .......................................................................................................... 37
Figure 29 - Serial Connection on LCD ........................................................................................................................... 38
Figure 30 - LCD/Microcontroller Interconnection ........................................................................................................ 39
Figure 31 - Hardware multipliers for MSP430 ............................................................................................................. 42
Figure 32 - MSP430 Architecture ................................................................................................................................. 42
Figure 33 - Low Power Speaker for audible tones ........................................................................................................ 44
Figure 34 - Voltage vs. percent of charge left .............................................................................................................. 45
Figure 35 - LED to display fault codes .......................................................................................................................... 47
Figure 36 - Cycle Life vs. Depth of Discharge ............................................................................................................... 49
Figure 37 - Spiral Cell vs. Rectangular Cell AGM Battery ............................................................................................. 50
Figure 38 - Optima Battery Comparison ...................................................................................................................... 50
Figure 39 - Schematic Diagram for 12 VDC Supplied by Optima D51 Battery ............................................................. 51
Figure 40 – MPPT Comparison Chart ........................................................................................................................... 52
Figure 41 – Spec’d MPPT Charge Controllers ............................................................................................................... 53
Figure 42 – Wind Turbine Comparison Chart ............................................................................................................... 55
Figure 43 – One Line Diagram ..................................................................................................................................... 56
Figure 44 – Wind Speed vs. Watts Produce of the Sunforce 45444 Wind Turbine....................................................... 57
Figure 45 – Solar/Wind Charging Diagram .................................................................................................................. 57
Figure 46 - Thin Film Array Solar Panel Specifications ................................................................................................. 59
Figure 47 - PV Array ..................................................................................................................................................... 60
Figure 48 - Mirrors on a Solar Panel ............................................................................................................................ 60
Figure 49 - Current Sensor with DC lines going to battery as well as data lines going to MSP430 ............................. 61
Figure 50 - Airflow Pattern to dissipate heat on board and display ............................................................................ 62