The document discusses testing various electrical machines to generate iso-efficiency maps. It tests a switched reluctance machine, DC machine, and squirrel cage induction machine. The test rig includes a dyno machine as a load controlled by a computer interface. The interface sends speed and torque commands to the drive from a data acquisition system. It provides isolation and sets the speed command. The goal is to compare the iso-efficiency maps of each machine to determine the most efficient for applications like electric vehicles. Future work includes testing other machines and automating more measurement points.

1. Background
Test machines:
● Electrical motor driven systems contributes 43-46%
of global energy consumption[1]
● Conventional fuel car has only 12-20% of total
efficiency[2] -- Electrical car is the trend of future
● Key equation:
Type: Switched
Reluctance Machine
Voltage: 380/415V
Current: 9A
Speed: 1500rpm
Output: 4kW
Type: DC Machine
Field:Shunt
Voltage:220/210VDC
Current: 27.6/0.67A
Speed:1250/1500rpm
Output: 5kW
Type: Squirrel cage
Induction Machine
Voltage: 415V Star
Current: 11A
Speed: 1500rpm
Output: 2.2kW
Test result and analysis
Iso-efficiency Map for SC IM
● Matlab contour plotting
● Prediction based on research
● Low efficient at low speed
● Highest efficiency at relative
higher speed and lower torque
than rated value
Iso-efficiency Map prediction for
DC machine and SRM
Computer Interface
It consists of two parts:
● Digital output
○ isolation interface
Transmit digital
signals to start, stop
and reverse the test
machine
System layout
● The Dyno machine acts as load and H2 drive
controls the torque systemically
● The computer receive real-time feedback from
power analyser and torquemeter
● The control system send speed and torque
command through Data Acquisition (DAQ) until
certain condition is achieved
What:
The computer interface
is basically an interface
to be connected
between the DAQ and
the drive
Aim
The major task is to explore the iso-
efficiency map for a variety of electrical
machines, including brushed DC machines,
switched reluctance machines (SRM) and
squirrel cage induction machines (SC IM),
then compare and analyse the iso-efficiency
maps for each type of the electrical
machines.
Why is iso-efficiency map important?
Iso-efficiency map describes the efficiency of
each operating point on the torque-speed
operating region. With the iso-efficiency map
of each type of electrical machines, industry
could predict the energy consumption in
particular application, e.g. electric cars, then
select the most efficient electrical machine,
thus energy could be saved.
Future Work:
● DC and SRW Machine
○ Repair SRM Driver
○ No load test
○ Integration into System
○ Drive Testing via LabVIEW
● Test other Electrical Machine
Why:
● The drive could
control the machine
according to the
commands sent
from the DAQ
● Provide isolation
protection to the
test equipment
● Analogue output
isolation interface
○ Set the speed
command to drive
[4][3]
Reference
[1]D. Maheswaran et al., “Energy Efficiency in Electrical Systems”, in 2012 IEEE Int. Conf. Power Electron., Drives and Energy Syst.., Bengaluru,
India, 2012.
[2]S.S. Williamson et al., “Comprehensive Drive Train Efficiency Analysis of Hybrid Electric and Fuel Cell Vehicles Based on Motor-Controller
Efficiency Modelling”, IEEE Trans. Power Electron., Vol.21, No.3, May 2006.
[3]Wen Soong, “DC Machines: Parameter Measurement and Performance Prediction”, Power Eng. Briefing Note Series, May 2008.
[4] S. M. Lukic and A. Emado, “Modeling of electric machines for automotive applications using efficiency maps,” in Proc. Elect. Insul. Conf. and
Elect. Manuf. Coil Winding Technol. Conf., Sep. 23–25, 2003, pp. 543–550.
● SC IM
○ Automation Testing
○ Higher number of
measurement point
● Computer interface
○ Print PCB board