This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: ⋅ = f rated 60 Hz ⋅ = a. Assuming volts per hertz control of the motor, the voltage must be reduced proportionally to the frequency when frequency drops below rated frequency Solution HP rated 100 hp ⋅ = V rated 460 V ⋅ = Problem 9-5 n rated 3560 rpm ⋅ = rpm 1 min ≡ f. The approximate operating speed can be found by calculating the synchronous speed at 85 hz and then subtracting the slip speed At 60 hz, the motor runs a 3560 rpm at full load indicating 40 rpm of slip n s85 120 85 ⋅ 2 = n s85 5.1 10 3 × = rpm so the operating speed is 5060 rpm...
View Full Document
This note was uploaded on 03/26/2012 for the course ECET 231 taught by Professor Piller during the Spring '12 term at Purdue.
- Spring '12