What does VVVF stands for in VVVF drive ?
How does it differ from VVF drive?
- 8 Answers
- 42450 Views
- HAL, I also Faced
- E-Mail Answers
Answer Posted / velu
vvvf means variable voltage variable frequency drives.ie.we
can vary the voltage & freqency thru freq converters
Ns = 120 * f /p
Ns= 120 *50 /4
6000/4 = 1500 rpm
Ns= 1500 rpm this is normal
if change the freq
120 * 40 / 4
4800 /4 = 1200
Ns= 1200 rpm
so 1500 rpm motor run at1200 rpm or below depending upon
our application
if you reduce the freq , the speed also reduce thru drives.
A variable-frequency drive (VFD) is a system for controlling
the rotational speed of an alternating current (AC) electric
motor by controlling the frequency of the electrical power
supplied to the motor.[1][2] [3] A variable frequency drive
is a specific type of adjustable-speed drive.
Variable-frequency drives are also known as
adjustable-frequency drives (AFD), variable-speed drives
(VSD), AC drives, microdrives or inverter drives. Since the
voltage is varied along with frequency, these are sometimes
also called VVVF (variable voltage variable frequency)
drives.The synchronous speed of an AC motor is determined by
the frequency of the AC supply and the number of poles in
the stator winding, according to the relation:
| Is This Answer Correct ? | 30 Yes | 5 No |
Post New Answer View All Answers
use of choke in APFC panels
What is the power factor of a transformer at no load?
Either the Armoured Earthing strip of HT 3 core cable have to pass through CB CT or not , why ???
What is creepage distance..... what will be the value for different voltage level
Usually in the L & T make MCC feeders' power circuit,we have BMR after the MAIN CONTACTOR.,can we interchange their position, keeping the control logic same???
what may the reason for vector shift in a generator?
If I have Energy Meter Ratio as 100:5 & Also I have CT Ratio as 50:5 then what will be my multiplying Factor(M.F.)
whats the differece between Exd and Exe
How to calculate the size of earth cable to earth the neutral of UPS ?
Its possible to use 3core 2R of 240 sq.mm cable for 3phases & separely 50sq.mm 3core cable fully for Neutral for connection of PCC to MCC 3ph..4wire system?
please send me the L&T Emb. sys. placement papers and entire details of pattren
how flow current in 220 kv line to line
When we have earthing mesh or underground earthing network in industrial plants, weather we have NT-S or NT-C-S kind of earthing system, so eventually weather we must use 4 or 5 wire in 400 volt level (For example 3×150+70 mm2 or 5×150 mm2) in this connection I would like to know exactly the paragraph of IEC or IEEE number
Draw a 230kv two-bus bar system showing the following. 1.Two generators (150MW) each connected through one 15.75/230KV transformers 2. 1 outgoing lines 3. Two 230/130 KV transformers 4. BUS PT's 5. CT
which metal is use in shunt
