Multiple Braking Resistors; Braking Resistor Types - ABB ACSM1 System Manual

Multiple braking resistors

In case two or more braking resistors are connected to braking choppers of
the drive modules, the same conditions as above must still be fulfilled.
•
The resistance R
R according to braking chopper data of the concerned ACSM1 drive
br,min
module
•
The resistance value R
fulfil the peak braking power requirements. In the following calculations
the value of U
• R
min( ) i
where P
br,max(i)
chopper.
•
The selected braking resistors should be able to handle the braking
energy generated in fast dynamic situations (time is just few seconds).
•
( P
br , cont
where E is the energy pulse rating of the individual resistor and
R(i)
P is the power rating of the concerned individual braking chopper.
br,cont(i)
•
The nominal power rating of the resistor must be adequate for the
average regenerative power.
•
( P
br , cont
where P is the nominal power rating of the individual resistor (steady
N,R(i)
state continuous load). For more detailed analysis (and more optimum
selection) the pulse load curves of the selected resistor should be
studied.

Braking resistor types

Resistor types JBR-xx for dynamic load cycles are available for ACSM1
drive modules. Please see ACSM1 hardware manual for the detailed data.
of each individual braking resistor must be at least
br(i)
of each individual braking resistor should also
br(i)
is 840V DC.
dc
< <
R
br P
( ) i
+
( P
br , max 1
is the braking power rating of the concerned braking
P
br , cont ( ) i
×
+ +
P ...)
1 br , cont 2
P
br , cont ( ) i
×
P
+ +
P ...)
1 br , cont 2
( )
2
U
dc
br , max( ) i ×
P
gen
+
P ...)
br , max 2
<
P dt E
gen R ( ) i
<
P
gen , ave N R , ( ) i
27
, max