Projects:2015s1-61 Computer Aided Measurement and Analysis of Equal Efficiency Characteristics of Electrical Machines
Contents
Project Group 61 information
Topic
Computer Aided Measurement and Analysis of Equal Efficiency Characteristics of Electrical Machines
Team
Student
Ka Kit Poon
Zeyu Chen
Kejie Huang
Supervisor
A. Prof. Nesimi Ertugrul
A. Prof. Wen Soong
Aim
The main goals of the project is to explore the iso-efficiency map for a variety of electric machines, including brushed DC machines, switched reluctance machines (SRM) and squirrel cage induction machines (SC IM), compare and analysis the iso-efficiency maps of different types of electrical machine and try to predict the energy consumption for applications which require time-varying torque-speed operation. Iso-efficiency map is a new concept to describe the efficiency at each operating point in the operating region. The process involves machine testing, system setup, data acquisition to obtain the resulted iso-efficiency map to form a comprehensive view of electrical machine efficiency characteristics. The expected iso-efficiency map for electrical machine is similar with K. Stockman’s work [1], this is a typical iso-efficiency map for an induction machine.
Motivation
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 and select the most efficient electrical machine, thus energy could be saved. In this project, the team carry out computer aided measurement and plotting of iso-efficiency map. It provided brief image about the efficient operating region of different machine.
Background
Proposed Approach
DC Machine
Switched Reluctance Machine
Squirrel Cage Induction Machine
The SC IM is a 2.2 kW Baldor machine. The induction machine is widely used in the industry. The drive used is Motiflex e100. It has a user-friendly interface and facilitate software configuration via "Mint WorkBench". As the manufacture has designed computer interface between drive and computer, the integration into the system does not take much time compared with DC and SWR Machine.
Dynamometer System
Electric Machine is integrated into the dynamometer system. The system facilitate accurate measurement of efficiency. The Dyno machine acts as load and H2 drive controls the torque systemically. The function of computer is to send command to the drives and received data from measurement equipment. The control system monitor measured value and compare with reference value. The computer send speed and torque command to drive until certain condition is achieved.
Reasult - Iso-efficiency Map of SC IM
The Squirrel Cage Induction Machine is integrated and tested in the Dynomometer system. The 10x10 speed amd torque value is measured. The iso-efficiency map has been plotted in MATLAB. The result shows that the machine operate efficiently at relatively high speed and low torque rather than rated value. The lowest efficiency is at low speed. It is found that the efficiency is increasing when higher torque is added to the test machine. One of the limitation is overload operating region. As the machine can only run overload for short time, the data set above rated torque is missing.
