Delta Electronics ASDA-B Series manual „ External Regenerative Resistor

Chapter 6 Control Modes of OperationASDA-B Series

recommend the users to use the regenerative resistors with thermal switches. As for the load characteristics of the regenerative resistors, please check with the manufacturer.

„External Regenerative Resistor

When using external regenerative resistor, connect it to P and C, and make sure the circuit between P and D is open. We recommend the users should use the external regenerative resistor that the resistance value following the above table 6.H. We ignore the dissipative power of IGBT in order to let the users easily calculate the capacity of regenerative resistor. In the following sections, we will describe Regenerative Power Calculation Method and Simple Calculation Method for calculating the regenerative power capacity of external regenerative resistors.

„Regenerative Power Calculation Method

(1) Without Load

When there is no external load torque, if the servo motor repeats operation, the returned regenerative power generated when braking will transmitted into the capacitance of DC bus. After the capacitance voltage exceeds some high value, regenerative resistor can dissipate the remained regenerative power. Use the table and procedure described below to calculate the regenerative power.

Servo Drive	Servo Motor (kW)	Rotor Inertia	Regenerative power from	Max. regenerative
			empty load 3000rpm to stop	power of capacitance
(kW)	(Frame Size)	J (kg. m2)
			Eo (joule)	Ec (joule)
0.1	0.1	0.037 E-4	0.179	3.11
0.2	0.2	0.169 E-4	0.818	4.5
	0.3	8.17 E-4	39.5
				6.22
0.4	0.4 (60 mm)	0.277 E-4	1.34
	0.4 ( 80 mm)	0.68 E-4	3.29
	0.5	8.17 E-4	39.5
0.75	0.6	8.41 E-4	40.7	11.07
	0.75	1.13 E-4	5.47
	0.9	11.18 E-4	54.1
1.0				13.5
	1 (100 mm)	2.578 E-4	12.5
	1 (130 mm)	8.41 E-4	40.7
1.5	1.5	11.18 E-4	54.1	18.18
	2 (100 mm)	4.239 E-4	20.5
2.0				22.5
	2 (130 mm)	14.59 E-4	70.6
	2 (180 mm)	34.68 E-4	168
		Table 6.I
Eo= J * wr2/182 (joule)		, wr : rpm

Revision January, 2009 6-33