college of engineering electrical engineering dept n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
College of Engineering Electrical Engineering Dept. PowerPoint Presentation
Download Presentation
College of Engineering Electrical Engineering Dept.

Loading in 2 Seconds...

play fullscreen
1 / 60

College of Engineering Electrical Engineering Dept. - PowerPoint PPT Presentation


  • 124 Views
  • Uploaded on

Power S ystem A rchitecture for Cubesat A Graduation Project presentation. College of Engineering Electrical Engineering Dept. Presented by: Abdulaziz Hilal AlKuwari Hassan Hisham Miqdad Ahmed Bassam Diab. Supervisors: Dr. Ahmed Massoud Dr. Tamer Khattab. Spring 2014.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'College of Engineering Electrical Engineering Dept.' - ivana


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
college of engineering electrical engineering dept

Power System Architecture for CubesatA Graduation Project presentation

College of EngineeringElectrical Engineering Dept.

Presented by:

AbdulazizHilal AlKuwari

Hassan Hisham Miqdad

Ahmed Bassam Diab

Supervisors:

Dr. Ahmed Massoud

Dr. Tamer Khattab

Spring 2014

presentation overview
Presentation overview
  • General Introduction About Cubesat.
  • Project Objectives.
  • System Divisions .
  • Time Schedule.
  • Simulation of QUbeSat Power System Architecture.
  • Test Results and Analysis
  • Modelling of the DC-DC Buck Converter.
  • Control of the DC-DC Buck Converter.
  • PV Model / Maximum-Power-Point-Tracking (MPPT).
  • Practical Implementation.
  • Project Cost
  • Future Work and Conclusion.
literature review
Literature Review
  • The satellite industry was only restricted to the space agencies and institutes till the first picosatellitewas created.
  • Cubesat design standards have been developed by the Joint cooperation of California Polytechnic State University (Cal Poly) at 1999.
  • Low Earth Orbit space missions.
  • Life span of about 9 months on an average.
literature review c ont d
Literature Review (cont’d)
  • General Cubesat standards and requirements
why cubesat
Why Cubesat?

Universities develop Cubesat because of :

  • The fact that the components needed to have complete satellite system are already available on shelf with lower cost.
  • It is a standardized system which makes it simple to design the system and launch it.
some previous cubesat missions cont d
Some Previous Cubesat Missions (cont’d)

Number of successfully launched Cubesats versus the date of launching:

mission of qu satellite qubesat
Mission of QU Satellite (QUbeSat)

Qatar university Cubesat (QUbeSat) mission is to map and observe the current waste disposal sites in Qatar and search for the illegally disposed waste in the desert.

gomspace.com

p roject o bjectives
Project Objectives
  • The aim of the project is to designpower supply architecture for the (QUbeSat) that is responsible for feeding all the satellite subsystems.
  • The architecture is composed of different stages including power generation, storage and finally distribution.
time schedule
Time Schedule

The over all project life is three years!

simulation of qubesat power system architecture
Simulation Of QUbeSat Power System Architecture
  • The overall power system architecture of QUbeSat has been simulated using MATLAB/Simulink.
  • The system losses (hence efficiency) are assessed including non-idealities of the system components under different scenarios.
simulation of qubesat power system architecture cont d
Simulation Of QUbeSat Power System Architecture(cont’d)

Solar Arrays

MPPT Converter

Transfers the maximum power from the solar array which maximizes the system efficiency.

  • The five side of the satellite are connected in parallel.
  • Type of the PV panels is triple junction.

gomspace.com

simulation of qubesat power system architecture cont d1
Simulation Of QUbeSat Power System Architecture(cont’d)

Battery Pack

Power Conditioning Converters

Power condition converters step down/up the voltage of the battery to supply the satellite subsystems

  • Lithium-ion type.
  • Two connected in parallel having a rated capacity of total 1800 mAh and nominal voltage of 7.4V.

gomspace.com

simulation of qubesat power system architecture cont d2
Simulation Of QUbeSat Power System Architecture(cont’d)
  • Open circuit voltage of the PV array is 5.38V.
  • Nominal voltage of the battery is 7.4V.
  • Aim of the MPPT-converter is to step up the PV array voltage to the battery level.
simulation of qubesat power system architecture cont d3
Simulation Of QUbeSat Power System Architecture(cont’d)

The schematic of buck converter (including imperfections)

The schematic of boost converter (including imperfections)

simulation of qubesat power system architecture cont d4
Simulation Of QUbeSat Power System Architecture (cont’d)
  • Three voltage levels to supply the loads.
  • The three converters simulated with the added imperfections.
  • The three converters are connected in parallel with the battery.
test results and analysis cont d
Test Results and Analysis (cont’d)

Case 1:

  • The power flow diagram below where the positive sign indicates loading and negative sign indicates supplying power
test results and analysis cont d1
Test Results and Analysis (cont’d)

Case 2:

  • The power flow diagram below where the positive sign indicates loading and negative sign indicates supplying power
test results and analysis cont d2
Test Results and Analysis (cont’d)

Case 3:

  • The power flow diagram below where the positive sign indicates loading and negative sign indicates supplying power
modeling of the dc dc buck converters
Modeling of the DC-DC Buck Converters
  • The step response of the converters shows large overshoot
  • Loads are sensitive to small voltage variations
  • The response can be improved closed loop control technique
  • An accurate model is needed to design the controller
modeling of the dc dc buck converters cont d
Modeling of the DC-DC Buck Converters (cont’d)
  • The most significant imperfections that appears in the converter are:
  • The voltage drop across the diode.
  • The voltage drop across the switch.
  • The on-state resistance of the diode.
  • The on-state resistance of the switch.
  • The ESR of the Capacitor.
  • The internal resistance of the inductor.
modeling of the dc dc buck converters cont d3
Modeling of the DC-DC Buck Converters (cont’d)
  • State space representation of the on-state mode of the buck converter
  • State space representation of the off-state mode of the buck converter
modeling of the dc dc buck converters cont d4
Modeling of the DC-DC Buck Converters (cont’d)
  • State Averaging
  • The switch is on at the time dT and off at the time (1-d)T. Thus the on-state and off state representations can be averaged as follow:
modeling of the dc dc buck converters cont d5
Modeling of the DC-DC Buck Converters (cont’d)
  • The Linearized Model of the Buck Converter
modeling of the dc dc buck converters cont d7
Modeling of the DC-DC Buck Converters (cont’d)
  • Result of the Buck DC- DC model

Ideal Converter

Derived Model Converter

Physical Converter

control of dc dc buck converters
Control of DC-DC Buck Converters
  • State Feedback Control
control of dc dc buck converters cont d
Control of DC-DC Buck Converters(Cont’d)
  • State Feedback Control with Integral Action
control of dc dc buck converters cont d1
Control of DC-DC Buck Converters(Cont’d)

The parameters used to simulate the converter

The gain vector was calculated based on the following time

domain specifications

pv model
PV Model
    • The aim of the PV model is to test the operation of the MPPT algorithm.
    • The available Practical PV Panel in the Lab is the 120W Polycrystalline BCT120-24.
  • The PV model chosen for the simulation is the Single-Diode general model.
pv model cont d
PV Model (Cont’d)
  • The P-V characteristic curve of the Simulated Polycrystalline PV Panel for different solar insolation and temperature respectively.
maximum power point tracking mppt
Maximum-Power-Point-Tracking (MPPT)
  • MPPT can be achieved by different approaches and techniques, but the well-known and widely used algorithm is the Perturb & Observe (P & O) method because of:
    • Its simple implementation.
    • Reasonable convergence speed.
  • P & O technique can be well visualized in the figure shown in the next slide.
maximum power point tracking cont d
Maximum-Power-Point-Tracking (cont’d)
  • The (P&O) MPPT illustration is on Buck converter.
maximum power point tracking cont d1
Maximum-Power-Point-Tracking (cont’d)
  • P&O method can be classified into:
    • Fixed perturb.
    • Adaptive perturb.
  • P&O with fixed perturb suffers some demerits and drawbacks:
    • Steady-state oscillations around the MPP due to fixed periodic tuning.
    • Possibility of tracking failure for rapid change of the atmospheric conditions especially the solar isolation.
  • The problem of steady-state oscillations can be minimized by applying small perturbation step-size, but results in slow down of the system.
maximum power point tracking cont d2
Maximum-Power-Point-Tracking (cont’d)
  • Many researches went through improving the P&O method and make it adaptive-based by utilizing an automatic variable perturb tuning in order to satisfy:
    • Fast tracking response toward the maximum power point.
    • Low steady-state oscillations.
  • Can be achieved by applying a large perturb value at starting to reach the MPP fast, then minimize the perturb value to result in lower steady-state oscillations.
maximum power point tracking cont d3
Maximum-Power-Point-Tracking (cont’d)
  • The simulation of the (P&O) algorithm has been performed on the available practical BCT120-24 PV panel to validate the functionality of the MPPT.
  • The converter used is Buck converter where its design parameters were chosen same as the practical design achieved in the lab.
maximum power point tracking cont d4
Maximum-Power-Point-Tracking (cont’d)
  • PV module power for sudden change of solar insolation and fixed temperature (fixed-perturb of = 0.0001).
maximum power point tracking cont d5
Maximum-Power-Point-Tracking (cont’d)
  • PV module power for sudden change of solar insolation and fixed temperature (adaptive-perturb of + (0.005 ×|dP/dV|)).
practical implementation
Practical Implementation
  • Converter Design Parameters.
practical implementation cont d1
Practical Implementation (cont’d)
  • State feedback Control on the 5V Buck converter
  • Open Loop Response
practical implementation cont d3
Practical Implementation (cont’d)
  • Practical Results of the (P&O) MPPT. (Taken at 2:00 PM on 30th of April 2014)

Fixed Perturb of = 0.005 (Transient and Steady-State)

practical implementation cont d4
Practical Implementation (cont’d)
  • Practical Results of the (P&O) MPPT. (Taken at 2:00 PM on 30th of April 2014)

Adaptive Perturb of = + (0.005 ×) (Transient and Steady-State)

practical implementation cont d5
Practical Implementation (cont’d)
  • In addition to the (P&O), MPPT has been also practically achieved using the Artificial Intelligence (Neural Network).
  • A sample of 39 PV-curves were taken on the 2nd of June 2014 from 9:40 AM till 4:00 PM every 10 minutes.
  • Those samples were used to train the Neural Network of MATLAB Neural Network wizard which uses Levenberg Marquardt (LM) training algorithm where the performance indices are the mean-squared-error (MSE) and the Regression index (R).
practical implementation cont d6
Practical Implementation (cont’d)

Taken at 1:40 PM on 4th of June 2014

practical implementation cont d7
Practical Implementation (cont’d)

Taken at 3:00 PM on 4th of June 2014

conclusion
Conclusion
  • A study was conducted about previous lunched cube-satellites
  • MPPT converter was designed, simulated and implemented.
  • PC converters were designed, simulated and implemented.
  • DC-DC Buck converter was modeled, simulated and practically controlled.
future work
Future Work
  • Implementation the real standard QUbeSat
  • Power management
  • Modeling of triple junction PV panel
  • Over-current protection