Table of Contents
The Detailed Design section contains finished and working documents pertaining to the detailed design of the Maximum Power Point Tracker to be delivered to AMSAT for potential use in the Fox-2 satellite.
Prototyping, Engineering Analysis, SimulationNo prototyping was performed, this circuit is largely too complex to do so effectively. Many of the circuits implemented are constructed using SMD components and are layout dependent. Due to the sheer amount of analysis performed on the design with secondary review by outside parties, we are confident that our solution is correct and will have minimal issues during board bring-up. Our constant communications with our guides and volunteer consultants familiar with our project requirements have been very helpful in defining this circuit.
We have performed an extensive amount of simulation with LTSpice:
P13271 LTSpice Simulations (Directory)
Please download LTSpice and open our .ASC files we have generated in the above link to our simulations folder.
A great resource for learning more about LTSpice and its powerful functionality can be found on the SwitcherCAD/LTSpice Yahoo Group. This is where much of the documentation can be found for LTSpice.
AMSAT MPPT Hardware Revision 1.0
These KiCAD files are those which were used to order Rev. 1.0 of the PCB and all schematics/bill of materials are those which do not represent anything added during or after the PCB bring-up. There are issues present in these files which were mitigated during PCB bring-up.
MPPT Rev. 1.0 Directory
MPPT Rev. 1.0 Archive (ZIP)
Library Files (ZIP)
AMSAT 7 Watt Maximum Power Point Tracker
These files represent the fully functional hardware and firmware that was delivered to Tony Monteiro of AMSAT following the conclusion of the senior design project at the end of the RIT Spring quarter (May 2013).
System Level Diagram
For reference when reviewing detailed documentation.
Hardware FilesOpening the KiCAD files may result in the default libraries to be used. It has been observed that some components will be incorrectly displayed if libraries are not correctly used. Some BJT devices have been observed to be displayed with incorrect pin placement. When in doubt, refer to the PDF schematics.
AMSAT 7W MPPT Files All KiCAD files (Zip).
Fox-2 MPPT Schematics (PDF)
Bill of Material (BOM)
Fox-2 MPPT BOM (PDF)
Fox-2 MPPT BOM (XLSX)
Health and Status FirmwareAll Health and Status firmware documentation can be found on the following EDGE wiki page
Health and Status Firmware (Directory).
Project ScopeThis diagram details the scope of our project as implemented in the red box:
Detailed Control System DiagramThis is a detailed control systems diagram only pertaining to the MPPT control circuitry:
Input/Output Voltage Control DiagramThis block diagram shows the input and output voltage control loop. Our MPPT will allow the output voltage to swing between 3.3V and 4.1V with a regulated input solar panel voltage. This is not a power supply. The output voltage is "regulated" only when the 4.1V maximum is reached:
Output Voltage "Soft" PWM Limit Block Diagram
Duty Cycle Control (PDF)
Duty Cycle Control (VSD)
Obtaining KiCad EDA Software
If you would like to use KiCad EDA, the software this project was created with, please download the latest version from the KiCad EDA project website.
The version of KiCad used for P13271 is indicated in the bottom-right corner of each schematic page.
Theory Of Operations Documents
The theory of operations documents aim to explain in detail the operation of individual subcircuits which are critical to the operation of the Fox-2 prototype maximum power point tracker.
Theory of Operations Directory
Theory of Operations Software Directory
RTD DriverRTD Driver Circuit Theory Of Operation (PDF)
RTD Voltage ScalingRTD Scaling Vmpp Matching Theory Of Operation (PDF)
Output Voltage "Soft" PWM LimitUC2524 "Soft" PWM Output Voltage Limit Theory Of Operation (PDF)
Output Voltage ClampOutput Voltage Clamp (PDF)
Output Voltage Clamp (DOC)
PWM Soft-StartPulse-Width Modulator Soft-Start (PDF)
DC/DC Buck ConverterNon-Synchronous Buck Converter (PDF)
Level-Shifting MOSFET DriverLevel-Shifting MOSFET Driver (PDF)
Test PlansPlease see the DDR presentation for our slide on test plan preparations. Actual plans will be added to this section once available.
The document from our SDR is still relevant to the DDR risks
Risk Assessment (PDF)
Risk Assessment (DOC)
Detailed Design Review
The presentation used during the P13271 Detailed Designe Review (DDR) held on February 15th, 2013.