39 lines
849 B
Markdown
39 lines
849 B
Markdown
# Avalanche Failure
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When max. voltage rating is exceeded and too much power is dissipated --> short circuit failure
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# dV/dt Failure
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High speed failure, not well understood.
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Voltage spike on drain --> translated to spike on gate, which destroys mosfet
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Happens very fast (ns)
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Generated by motor noise --> prevent motor noise!
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# Excess Power Dissipation
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Usually MOSFET heats up, unsolders itself!
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Doesn't necessarily fail.
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--> heat management
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# Excess Current
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High currents --> high temperatures (Power: I*I*R*t)
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Once again: heat management
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# Foreign object Damage
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Loose parts --> cause shorts or mechanical damage.
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# Jammed or blocked motor
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--> fast acting varistor transient absorber --> dissipates energy
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--> react with reducing speed in controller
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Rapid deceleration --> energy is gained and must be handled. Push into batteries? |