# Difference between revisions of "Generator Efficiency"

From DIDEAS Wiki

m |
m (→Electrial Efficiency) |
||

Line 6: | Line 6: | ||

E = Pout / (Pout + Ploss) | E = Pout / (Pout + Ploss) | ||

+ | |||

Pout = I^2 * Rl | Pout = I^2 * Rl | ||

Ploss = I^2 * Rm | Ploss = I^2 * Rm | ||

+ | |||

thus | thus | ||

+ | |||

E = I^2 * (Rl / (Rl+Rm)) | E = I^2 * (Rl / (Rl+Rm)) | ||

let Rl = k * Rm then | let Rl = k * Rm then | ||

+ | |||

E = k/(1+k) | E = k/(1+k) | ||

for a given desired efficiency keep | for a given desired efficiency keep | ||

+ | |||

Rl >= Rm * E/(1-E) | Rl >= Rm * E/(1-E) | ||

k = 4 -> 80% | k = 4 -> 80% | ||

k = 9 -> 90% | k = 9 -> 90% |

## Revision as of 08:02, 20 April 2007

# Electrial Efficiency

Efficiency as a fraction input mechanical power that is available at the output terminals:

E = Pout / (Pout + Ploss)

Pout = I^2 * Rl Ploss = I^2 * Rm

thus

E = I^2 * (Rl / (Rl+Rm))

let Rl = k * Rm then

E = k/(1+k)

for a given desired efficiency keep

Rl >= Rm * E/(1-E)

k = 4 -> 80% k = 9 -> 90%