C.1 Capacity Formulas - Delta Electronics Elevator Drive VFD-VL User Manual

Appendix C How to Select the Right AC Motor Drive|

C.1 Capacity Formulas

1. When one AC motor drive operates one motor
The starting capacity should be less than 1.5x rated capacity of AC motor drive
The starting capacity=
973
2. When one AC motor drive operates more than one motor
2.1 The starting capacity should be less than the rated capacity of AC motor drive
Acceleration time ≦ 60 seconds
The starting capacity=
×
k N
η
×
cos
Acceleration time ≧ 60 seconds
The starting capacity=
×
k N
[
n
T
η ϕ
×
cos
2.2 The current should be less than the rated current of AC motor drive(A)
Acceleration time ≦ 60 seconds
n
Acceleration time ≧ 60 seconds
+
n
T
C-2
⎛
×
k N GD
⎜ ⎜
+
T
η ϕ L
× ×
cos 375
⎝
⎡
[ ]
( )
+ =
⎢
n n k P 1
−
s s 1 C 1
T ⎢
ϕ
⎢
⎣
⎡ n
]
( )
+ = +
⎢
n k P 1
−
s s 1 C 1
⎢
n
⎢
⎣
n
⎡ ⎤
+ + ≤
I 1 k 1
⎛ ⎞
S
−
M ⎢ ⎜ S ⎟ ⎥
n
T
⎝ ⎠
⎣ ⎦
T
n
⎡ ⎤
+ ≤
I 1 k 1 the
⎛ ⎞
S
−
M ⎢ ⎜ S ⎟ ⎥
n
⎝ ⎠
⎣ ⎦
T
⎞
2
N
⎟ ⎟
× ≤ ×
1 5 . the _
t
⎠
A
n
⎤
( )
+ s ≤ ×
⎥
k 1 5 . the
−
s 1
⎥
n
⎥
⎦
T
⎤
( )
s ≤
⎥
k the _ capacity
−
s 1
⎥
⎥
⎦
T
×
1 5 . the _ rated _ current
_ rated _ current
capacity _ of _ AC _
_ capacity _ of _ AC _
_ of _ AC _ motor _
_ of _ AC _
_ of _ AC _ motor
Revision Nov. 2008, VLE1, SW V1.03
motor _ drive ( kVA )
motor _ drive ( kVA )
drive ( kVA )
motor _ drive ( A )
_ drive ( A )