This is a draft cheat sheet. It is a work in progress and is not finished yet.
Electric current
- Charge flow in materials
- Amount of electricity in circuit flow |
power
Coal-fired power plant
- 33% eff
Gas-fired power plant
- higher eff(heat source higher temp)
- more environmental friendly
Stream turbine
- convert energy of fluid into mechanical energy by expansion
- stream driven rotary engine |
Transformer
use induction
P=VI
Vs/Vp = Ns/Np = Ip/Is
Ns/Np>1 step-up |
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Voltage
Force or push on electron
Potential difference |
AC
frequency 50Hz(direction 100times)
line voltage easily up and down
need larger diameter
cheaper transformation between voltage
easy to off
less equipment, reliable
economical
rotating field |
Smart power grid
reliable
- real time info about electricity flow
- identify, correct potential problem before occur
- grid can respond to system and reroute
faster power restoration
- can auto know, no need customer call
more info about power usage |
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Resistance
opposition to current flow |
DC
flow in one direction
no skin effect, low loss
need DC-AC converter to control voltage level
switch to high voltage is difficult
long distance, higher power p2p transmission
- lower loss
undersea, underground transmittion
- no reactive power problem
less space |
Light
fire 1%, incandescent lamp 3.5% fluorescent lamp 20% LED 80% |
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