Transcript TEAM CACHE MONEY: SOLAR INSOLATION FORECASTING CRITICAL DESIGN REVIEW B. DiRenzo, L. Hager, A.

TEAM CACHE MONEY:
SOLAR INSOLATION FORECASTING
CRITICAL DESIGN REVIEW
B. DiRenzo, L. Hager, A. Fruge,
M. Dickerson, C. Duclos, N. Frank,
T. Furlong
Outline
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Overview
Subsystem 1: Remote Sensor
Subsystem 2: Remote Power Sensor and
Supply
Subsystem 3: On-grid PV Sensor
Subsystem 4: Server
Current Status of Project
Further Development
Updated Division of Labor
Updated Schedule
Power Output (W) from a PV Array
on a Cloudy Day vs. a Clear Day
*PV data provided by Professor Gasiewski in Boulder, CO
System Overview
Subsystem 1: Remote Sensor
Android Timing App Architecture:
B. DiRenzo
Samsung Galaxy S3
- 3G HSDPA* 850 / 900 / 1900 / 2100 and 4G LTE
- Accelerometer, gyro, proximity, compass,
barometer sensors
- A-GPS support and GLONASS
- Li-Ion 2100 mAh battery
- Android OS 4.1.2
- Quad Core 1.4GHz Cortex-A9
processor
- 8MP camera
- Micro USB port
*High Speed Packet Access
AP003039 Wide Angle Camera Lens
- 0.60X zoom factor
- No perspective distortion
- Easy attachment
- Field of view created:
Horizontal: 72o
Vertical: 51o
Diagonal: 82o
- ~ 65% increase in angle of
view WRT standard lens
Subsystem 2: Remote Power
Sensor and Supply
M. Dickerson
Solar Panel (AB1-70)
- 34.10V and 2.08A at maximum output
- 70W maximum output
- 1200mm x 600mm
- 90% power output after 10 years
- 80% power output after 25 years
Charge Controller (PT-12-24-5TC)
- 0-45V input, 50A max input
- 10-30V output depending
on connections
- 0-57A output, depending
on power from panel
- Can connect to a high
voltage panel (34V) and
a 12V battery
- ~94% efficiency
Battery (PS-12350)
- 12V, 35AH AGM* Sealed Lead-Acid
- -4oF (-20oC) to 122oF (50oC) operating
temperature range
- 0.35A draw from buck
converter -> capable of
maintaining phone power
up to 100 hours
*Absorbent Glass Mat: provides up to 5x faster charging WRT flooded batteries
Buck Converter:
F
V
F
H
Ω
Ω
F
Ω
2
F
Ω
LT1375 Simulation Results:
Simulated with 5Ω load to simulate phone
LT1375 Buck Converter IC:
- 500kHz, buck switching regulator
- Up to 1.5A output
- 25V max input voltage
- High efficiency
- ~350mA current draw
Individual Component Tolerances:
- All resistors rated at 1/4W
Capacitor Tolerances:
- 100uF tantalum capacitor rated at 10V
- All other capacitors rated at 50V
Diode Tolerances:
- 1N914 diode rated at 100V
- 1N5818 Schottky diode rated at 30V
Power Supply Parts List
- All parts are available from
many manufacturers
- If LT1375 is not used, basic
component list will remain
constant, with altered values
- All parts shown to the right,
except for USB cable
Buck Converter Results
- Internal phone circuitry allows phone to charge at a voltage of
4.5-6V both safely and effectively
o Due to USB "standard" of 5V + 10% (although most companies design USB
outputs with 5V + 5% at most)
- Graph to the right measured
using oscilloscope, which
seemed to introduce noise
- Loaded voltage: 5.02V + 3%
- When measured with multimeter VR ≅ 0.37-0.38%
- Loaded voltage: 4.97V
Subsystem 3: On-grid PV Sensor
L. Hager
AS8002 Power Measurement IC
-12 Bit 100kSPS ADCs
- Programmable gain amplifiers
- On chip voltage reference
- SPI compatible interface
- Fast over-current detection
AS8002 Pin Layout
Pin
Description
IOP_VOP
Positive current input
IOM_VOM
Negative current input
V1P
Positive voltage input
V1M
Negative voltage input
REF
Positive input reference
voltage
SDO (MISO)
Serial Data Output (SPI)
SDI (MOSI)
Serial Data Input (SPI)
SCLK
Serial Clock (SPI)
SCSB (SS)
Serial Chip Select (SPI)
Arduino Due
- 32 bit ARM processor
- Up to 96MHz clock
- Open source C++ based wiring language
- Programmable SPI bus
w/ capability of
communication to
multiple devices
Arduino WiFi Shield
- Connects via 802.11 g/b networks
- WEP and WPA2 encryption
- Easy connection to Arduino via SPI bus
- Open source firmware
N. Frank
Subsystem 4: On-grid PV Sensor
Subsystem 5: Server
T. Furlong
Subsystem 5: Server Architecture
TCP Socket Network
- Able to receive many
images simultaneously
- Receives through a
static IP address
- Uses time taken as the
image filename
- Times the saving of
images
- Debug mode to display
useful information
Mosaic Imaging (Stitching) Test
Example
An example of base images used for testing the mosaic imaging algorithm:
C. Duclos
Mosaic Imaging (Stitching) Test
Results
* Average elapsed time: 5.4 seconds
Motion Vector Detection Test
Results
Motion Vector Detection Test
Results
*Average elapsed time: 1.2 seconds
Scale Invariant Feature Transform
(SIFT) [1]
SIFT Keypoint:
- Circular image region described by four parameters: the keypoint center
coordinates x and y, its scale (the radius of the region), and its orientation (in
radians).
Scale Invariant Feature Transform
(SIFT) [1]
SIFT Detector:
- Detects "blobs" by constructing a "Gaussian scale space”: a collection
of images obtained by gradually reducing the image resolution
("smoothing").
- Keypoints are refined by eliminating the unstable: nearby an image edge
or are found on image structures with low contrast.
- Invariant to translation, rotations, and scaling of the image.
SIFT Descriptor:
- Characterizes the keypoint with a 3-D spatial histogram of the image
gradients. The gradient at each pixel is the sample of a 3-D elementary
feature vector, formed by the pixel location and the gradient orientation.
Samples are weighed by the gradient norm and accumulated in a 3-D
histogram (descriptor).
- Used for matching of SIFT points.
[1] www.vlfeat.org
SIFT Matching Example
1.
Both mosaic imaging and motion vector detection algorithms find potential
matches of SIFT keypoints (left image).
1.
Then refine the matches by ranking them based on their "scores" (Euclidean
distance between the two points) and finds the random sample consensus
(RANSAC) throwing out the outliers (right image).
Current Status of Project
Functioning remote power sensor:
- Sending images to server
Functioning On-grid PV sensor:
- Communicating through SPI interface to
arduino
Server:
- Stitching images together and outputting
vectors
motion
Remote Power Supply:
- Simultaneously charges phone and battery
N. Frank
Further Development
Remote Smartphone Sensor:
- Create power saving class
- Timing system development
- Environmental protection
Remote Power Supply:
- Implement fully designed buck converter
- Time permitting develop charge
controller
Further Development Continued
On-grid Sensor:
- Simultaneous communication between SPI
bus and Wifi shield
- Fabrication of PCB
Server:
- Forecasting algorithm
- Overlaying forecast maps on Google maps
- GUI
Preliminary Parts List
- Samsung Galaxy S3 (3)
- Wide angle camera lens (3)
- Arduino IOIO board (3)
- Solar Panel (AB1-70) (3)
- LT1375 Buck Inverter (3)
- Arduino Wifi shield (3)
- Arduino Due (3)
- AS8002 (6)
Updated Division of Labor
Updated Schedule