Delta Electronics AC Servo Drive ASDA-B - Manual (Page 147)

Chapter 6 Control Modes of Operation|ASDA-B Series
6-32 Revision February 2008, Doc. Name: 2006PDD23000009
6.6.3 Regenerative Resistor
„ Built-in Regenerative Resistor
When the output torque of servo motor in reverse direction of motor rotation speed, it indicates that
there is a regenerative power returned from the load to the servo drive. This power will be transmitted
into the capacitance of DC Bus and result in rising voltage. When the voltage has risen to some high
voltage, the servo system need to dissipate the extra energy by using a regenerative resistor. ASDA-B
series servo drive provides a built-in regenerative resistor and the users also can connect to external
regenerative resistor if more regenerative capacity is needed.
The following table 6.H shows the specifications of the servo drive’s built-in regenerative resistor and
the amount of regenerative power (average value) that it can process.
Built-in Regenerative Resistor Specifications
Servo Drive
(kW)
Resistance (Ohm)
(parameter P1-52)
Capacity (Watt)
(parameter P1-53)
Regenerative Power
processed by built-in
regenerative resistor (Watt) * 1
Min. Allowable
Resistance (Ohm)
0.1 No built-in regenerative resistor - 40
0.2 No built-in regenerative resistor - 40
0.4 No built-in regenerative resistor - 20
0.75 40 60 30 20
1.0 40 60 30 20
1.5 40 60 30 20
2.0 40 60 30 10
*1: Regenerative power calculation: The amount of regenerative power (average value) that can be
processed is rated at 50% of the capacity of the servo drive’s built-in regenerative resistor. The
regenerative power calculation method of external regenerative resistor is the same.
Table 6.H
When the regenerative power exceeds the processing capacity of the servo drive, install an external
regenerative resistor. Please pay close attention on the following notes when using a regenerative
resistor.
1. Make sure that the settings of resistance (parameter P1-52) and capacity (parameter P1-53) is set
correctly.
2. When the users want to install an external regenerative resistor, ensure that its resistance value is
the same as the resistance of built-in regenerative resistor. If combining multiple small-capacity
regenerative resistors in parallel to increase the regenerative resistor capacity, make sure that the
resistance value of the regenerative resistor should comply with the specifications listed in the
above table.
3. In general, when the amount of regenerative power (average value) that can be processed is used
at or below the rated load ratio, the resistance temperature will increase to 120°C or higher (on
condition that when the regeneration continuously occurred). For safety reasons, forced air cooling
is good way that can be used to reduce the temperature of the regenerative resistors. We also