KEB COMBIVERT F5-A - Page 493

General design
© KEB, 2012-10 COMBIVERT F5-A, -E, -H Page 9.1 - 5
9
Formula
1. Braking time without braking resistor 2. Braking torque (necessary)
(J
M
+ J
L
) • (n
1
- n
2
)
——————————
9.55 • (K • M
N
+ M
L
)
(J
M
+ J
L
) • (n
1
- n
2
)
————————
9.55 • t
B
t
Bmin
= M
B
= - M
L
Valid range: n
1
> n
N
Condition: M
B
< 1.5 • M
N
(Field weakening range) f < 70 Hz
3. Peak braking power 4. Braking time with braking resistor
M
B
• n
1
—————
9.55
(J
M
+ J
L
) • (n
1
- n
2
)
P
B
= t
Bmin
* ————————————————
9.55 • K• M
N
+ M
L
+
P
R
• 9.55
—————
(n
1
- n
2
)
Condition: P
B
< P
R
Valid range: n
1
> n
N
P
R
• 9.55
——————
(n
1
- n
2
)
Condition:
< M
N
• (1.5 -K)
f < 70 Hz
P
B
< P
R
K= 0.25 for motors upto 1.5 kW J
M
= mass moment of inertia motor [kgm
2
]
0,20 for motors 2.2
upto
4 kW J
L
= mass moment of inertia load [kgm
2
]
0.15 for motors 5.5
upto
11 kW n
1
= motor speed prior to deceleration [rpm]
0.08 for motors 15
upto
45 kW n
2
= motor speed after deceleration
(standstill = 0 rpm)
[rpm]
0.05 for motors > 45 kW n
N
= rated motor speed [rpm]
M
N
= rated motor torque [Nm]
M
B
= Braking torque (necessary) [Nm]
M
L
= load torque [Nm]
t
B
= braking torque (necessary) [s]
t
min
= minimum braking time [s]
t
Z
= cycle time [s]
P
B
= peak braking power [W]
P
R
= peak power of braking resistor [W]