Team 2 Solar Kiosk Project

1
Team 2Solar Kiosk Project

• Sponsored by
• Team Members
• Jakub Mazur - Manager
• Eric Tarkleson Presentation/Lab
• Josh Wong - Webmaster
• Ben Kershner Document Preparation

2
Current Sensing

• Applications
• Pros Cons
• The Hall Effect
• Shunt Resistors
• Making your Data useful
• Questions

3
Applications

• Measuring Power Consumption
• Design for Safety
• GFCIs, fuses, circuit breakers
• Temperature optimization
• High current hotter components

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Shunt Resistors vs Hall Effect
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• Shunt Resistor
• Low failure probability
• Cheap
• Wastes power
• Not suitable for all currents
• Limited sensing range
• Requires additional voltage measurements

• Hall Effect Sensor
• Isolated from current source
• Higher precision
• Passive device
• More expensive
• Can be integrated into an IC device

6
The Hall Effect

• When there is a Magnetic field in the presence of
  a conductor a voltage is induced due to electron
  and hole drift
• Electron negative charge carrier
• Hole positive charge carrier

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Hall Effect
VH
t
W
L
I

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The Hall Effect - Math

• Vhall -(IB)/(dne)
• Rhall -1/(ne)
• current through wire
• Bfield UoIp/(2pir)

• I current
• B Mag Flux Dens
• d depth of plate
• e electric charge
• j current density
• n charge carrier dens
• r distance to center of wire
• Uo 4pi10-7

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So what?

• We can use this to our advantage
• We can detect
• B field
• Current
• Voltage
• Charge drift velocity
• We can do this without having inline components
  (like a shunt resistor)