2
Any Voltage Elmo’s Gold Servo Drives support a large voltage range:
from 10VDC to 800VDC
from 30VAC to 530VAC
They are divided into a few operating ranges and Elmo’s DC Bus offers the following:
10VDC -100VDC
40VDC- 200VDC
100VDC- 400VDC
200VDC - 800VDC
3
Any Voltage For non-standard, justified requests:
10VDC- 48VDC
10VDC- 60VDC
These two are needed mainly for greater efficiency with very high current drives
Why justified requests? Usually suits applications with special not standard needs
4
Any Voltage The Tambourine
A compact, direct-to-mains power supplies for servo applications, up to 530 VAC
TAM
VP +
VN -
Elmo Isolated Drive
TAM001A
-t°
U
AC2-t°
-t°
U
U
AC1
AC3
PE
C.M.CThree Phase
Mains AC network
VP +
VN -
Neutral (0)
Safety Regulations
Earth (PE)
Rshunt
PE
AC1
AC2
AC3
PE
For more about power supplies:
http://www.elmomc.com/products/servo-power-supplies.htm
http://www.elmomc.com/applications/Power-Supply-for-Servo-Applications.htm
5
Any Voltage
Power supplies for servo applications must have:
adequate DC Bus
sufficient power resources to drive the loads
voltage variations within acceptable limits
bi-directional energy flow
high-frequency power handling
6
Any Voltage
Power supplies for servo applications must:
meet safety standards
comply with EMC, Immunity & Emission +
limit and control the inrush current
control & limit leakage currents
withstand tough environmental requirements (vibrations, temperature, humidity, etc.)
9
Any Voltage Elmo recommends a shared DC Bus in any application with a number of axes >2.
Advantages include:
Sharing the power Bus resources
Regeneration sharing
Sharing the safety, protections, EMI, etc.
10
Any Voltage
The shared DC Bus
yields a more powerful DC source for each drive
more powerful, efficient and practical regeneration
saves 5% - 8% of the power consumption
reduces the amount of external, mandatory components (circuit breakers, contactors, filters, etc.)
reduces space (for > 2 axis applications)
decreases heat dissipation
diminishes stress from the AC network
cuts overall costs (for > 2 axis applications)
11
Any Voltage Single phase or 3 phases?
Single phase is more cost effective
Three phases are technically better as they provide more stability, have less ripple, more balanced network loading, etc.
Up to a few KWs (2 KW- 3 KW) the single phase is a reasonable compromise
Single phase neutral conductor must usually be limited to <30 A - 40 A
Single phase 230 VAC servo drives and motors cost less and are more common (especially in the Far East) than 400 VAC servo drives and motors
12
Any Voltage
So, which voltage to choose?
The mandatory rule is that:
The voltage must be able to satisfy the needs of the speed & torque/force
Then select according to constraints or convenience
13
Any Voltage
Which voltage to choose?
Constraints:
The motor determines the voltage. In many cases, such as Direct Drive (linear or rotary), a very high voltage is needed to achieve speed and current requirements.
The Bus of the application is given. For example: battery 24 VDC, 48 VDC machine’s Bus etc.
A transformer should not be required
14
Any Voltage
Which voltage to choose?
Convenience:
The freedom to select. Given only the speed and torque/ force allows selecting the optimum combination of motor windings, drive’s size and thus the operating voltage.
Massive multi-axis. For example: an application with 61 axis X 1.5 KW (a real case). The question is: what is more convenient ─ 100KW isolation transformer or direct-to-the-mains 3X400 VAC?
For High power (>15 KW) the 3X400 VAC is much more convenient than any other voltage Bus.
15
Any Voltage
Which voltage to choose?
Convenience:
Working direct-to-the-mains is always more convenient and saves the need for an isolation transformer, but it’s not always better!
For more about power supplies:
http://www.elmomc.com/products/servo-power-supplies.htm
http://www.elmomc.com/applications/Power-Supply-for-Servo-Applications.htm
16
Any Voltage
Gold Servo Drive Standard Compliance
Each DC input is independently compliant with:
Safety standards
UL508c
IEC61800
UL60950
EMC standards
IEC61800-3