* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Kumu a`o Cubesat
Survey
Document related concepts
Coupon-eligible converter box wikipedia , lookup
Television standards conversion wikipedia , lookup
Analog-to-digital converter wikipedia , lookup
Resistive opto-isolator wikipedia , lookup
Surge protector wikipedia , lookup
Operational amplifier wikipedia , lookup
Carbon nanotubes in photovoltaics wikipedia , lookup
Schmitt trigger wikipedia , lookup
Voltage regulator wikipedia , lookup
Integrating ADC wikipedia , lookup
Current mirror wikipedia , lookup
Power electronics wikipedia , lookup
Electric battery wikipedia , lookup
Switched-mode power supply wikipedia , lookup
Transcript
KUMU A’O CUBESAT 1 Amy Blas March 7, 2008 WHAT IS CUBESAT? 10x10x10 centimeter cube Launched in lower earth orbit (LEO) Started last semester 13 members Objective is to be the first CubeSat in space from Hawaii 2 3 THE DIFFERENT SUBSYSTEMS Tele-Communication Command and Data Handling (C&DH) Thermal Structural Electrical Power (EPS) 4 BLOCK DIAGRAM OF EPS Solar Cells Step Up Converter Battery Charger DC-DC Converter Battery Gauge Electronic Components Battery Pack C&DH 5 BLOCK DIAGRAM OF EPS Solar Cells Step Up Converter Battery Charger DC-DC Converter Battery Gauge Electronic Components Battery Pack C&DH 6 SOLAR CELLS Spectro Lab’s Improved Triple Junction (ITJ) 26.8% efficiency Solar Cells Integral bypass diode protection Transparent insertion into existing systems 7 SOLAR CELLS 1 Set = 2 Series Cells 12 cell configuration Current Sensor 10 cm 10 cm 10 cm Each cell is 4 x 7 cm 2.32 V per cell 4.64 V and 450.8 mA per side Blocking Diode (prevent power drain) Bypass Diode 8 8 CURRENT SENSORS Texas Instruments INA138-Q1: High-Side Measurement Current Shunt Monitor 1 placed at each side Used to see orientation of Cube 9 BLOCK DIAGRAM OF EPS Solar Cells Step Up Converter Battery Charger DC-DC Converter Battery Gauge Electronic Components Battery Pack C&DH 10 STEP-UP CONVERTER – MAX1771 2 to 16.5V Input Voltage Range 90% Efficient for low load currents Output current range of 30mA to 2A Preset 12 V or adjustable output voltage Set by input voltage of charger 5V 11 BLOCK DIAGRAM OF EPS Solar Cells Step Up Converter Battery Charger DC-DC Converter Battery Gauge Electronic Components Battery Pack C&DH 12 BATTERY CHARGER – MAX1898 Simple circuit design 4.5 to 12V input range Programmable charge current Output voltage of 4.1V Internal current sense resistor 13 BLOCK DIAGRAM OF EPS Solar Cells Step Up Converter Battery Charger DC-DC Converter Battery Gauge Electronic Components Battery Pack C&DH 14 LITHIUM ION CELLS Saft MP 176065 Lithium Ion cell Nominal Voltage: 3.7 V Cycle Life: > 600 cycles @ C/2 to 100% DoD Capacity of 7 Ah Discharge cut off voltage : 2.5 V End charge voltage of 4.2+/-0.05V 15 BLOCK DIAGRAM OF EPS Solar Cells Step Up Converter Battery Charger DC-DC Converter Battery Gauge Electronic Components Battery Pack C&DH 16 FUEL GAUGE Texas Instruments bq2060A: Compliant Gas Gauge IC External EEPROM stores configuration information Battery’s chemistry Self-discharge rate Rate compensation factors Measurement calibration Design voltage and capacity Accurately adjusts remaining capacity for use and standby conditions based on Time Rate Temperature 17 BLOCK DIAGRAM OF EPS Solar Cells Step Up Converter Battery Charger DC-DC Converter Battery Gauge Electronic Components Battery Pack C&DH 18 DC-DC CONVERTER MAX1703(step-up) Fixed 5V output voltage Up to 95% efficiency 0.7 to 5.5V input Range Up to 1.5A output 19 MAX1703- PCB ARTIST SCHEMATIC 20 DC-DC CONVERTER o MAX 1771 : 6V step-up o 2 to 16.5V Input Voltage Range o 90% Efficient for low load currents o Output current range of 30mA to 2A o Preset 12 V or adjustable output voltage o Set by input voltage of charger o External resistors can be used to set the output voltage 21 MAX1771- PCB ARTIST SCHEMATIC 22 DC-DC CONVERTER MAX1921(step-down) Up to 90% efficiency 2 to 5.5V input range Fixed 3.3V output voltage Guaranteed 400 mA output current Up to 1.2MHz switching frequency Operating temperature range of -40 to +85°C 23 MAX1921- PCB ARTIST SCHEMATIC 24 EPS PCB ARTIST SCHEMATIC 25 EPS PCB ARTIST- PCB DESIGN 26 PROBLEMS Complications with PCB artist Not enough room on PCB Wrong values for resistors, capacitors, etc. Connection errors Running out of Time 27 EPS Schedule (Gantt Chart) Week 1 2 3 January 14 21 28 Date Presentations Design Orientation Proposal Preliminary Design Critical Design Final EPS PCB artist Ina 138 Max 1771 Max 1898 Max 1771 Max 1703 BQ 2060A Prototyping Breadboard Ina 138 Max 1771 Max 1898 Max 1703 Max 1771 BQ2060A Test Receive Parts Test PCB layout Combine subsystems Reports Draft Final 4 4 5 6 February 11 18 7 8 25 3 9 10 11 March 10 17 24 12 13 31 7 14 15 April 14 21 16 17 May 28 5 Any Questions? 29