AVTC Model Based Design Curriculum Development Project

Lesson 1: System Development

Outline Electric drives Introduction to Power Electronics Rectifiers Inverters Simulink Models Simscape Models Failure Modes

Electric Drives What is an Electric Drive? – Conditions power to motor, responds to driver request and provides feedback loop from motor to controller logic Monitors characteristics of the electric motor such as temperature, torque, speed and angular position Source:

Electric Drive Electric Motor Electric Drive 3-φ output voltage DC input voltage Source:

Block Diagram of the Drive Basic functionality of the drive Input Electric Drive Inverter Controller Electric Motor

Introduction to Power Electronic Devices

Four Quadrant Operation of Electric Drive Illustrated by: Shrikanthv

0 2-Step and 3-Step Waveform 3-Step Waveform 2-Step Waveform 0 t t

5- Step Waveform 0 t

Three-Step 3-φ Waveform Phase A Phase B Phase C t t t

Comparison Between Different Waveforms Waveform Signal Transitions per Period System Description Total Harmonic Distortion 2 2-level square wave 45% 4 3-level square wave >24% 8 5-level square wave >7%

Regeneration When the motor is operated as a generator, the power is fed back to the batteries through rectifiers

Basic Principle of Rectifiers It converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction 1-φ AC

Simulink Model of Basic Rectifiers Half-wave rectifier: Full-wave rectifier:

3-φ Full-Wave Rectifier The output response of a 3-φ full-wave rectifier is shown below:

Inverter The DC power from the batteries is converted to AC power by Inverters to supply 3-φ motor i

Basic Principle of Inverters It converts DC voltage to AC voltages We will demonstrate: –DC to 1-φ AC –DC to 3-φ AC There are different types of conversion techniques among them Space Vector Modulation is prominent Inverter Alternating Current Direct Current

The principle of space vector modulation is based on the application as shown below in the hexagon As the transistors in the basic 3-φ inverter are switched on and off, six possible active switching vectors V1 through V6 are actualized Basic Principle of Space Vector Modulation Source:

Space Vector Timing Diagram The timing sequence and the resulting switching waveform for Symmetric Sequence SVM in sector 1 is shown below Source:

2- Step Inverter

3-Step Inverter

5- Step Inverter

3-Step 3-φ Inverter

Simscape Model of 3-φ Inverter

Simscape Response of 3-φ Inverter

Specifications Used with Simscape Models AC Motor Drive DC Motor Drive Stator Resistance: 1.48 mΩ Rotor Resistance: 9.29 mΩ Inductance: mH Moment of Inertia: 10 kg- m 2 Friction Coefficient: 0.08 N-m-s Armature: Resistance: 56 mΩ Inductance: 0.15 mH Field: Resistance: 150 Ω Inductance: 113 H DC Source: 150 V Moment of Inertia: 10 kg- m 2 Friction Coefficient: N-m-s Smoothing Inductance: 0.5 mH

Simscape Model of Two Quadrant DC Motor Drive

Speed and Torque Response of Two Quadrant DC Motor Drive

Simscape Model of Induction Motor Drive

Speed and Torque Response of AC Motor Drive

Failure Modes – DFMEA Line No: Function of Part Potential Failure Mode Potential Effects of Failure SEVSEV Potential Cause OCCOCC Current Design Controls Prevention Current Design Controls Detection DETDET RPN 1 Inverter: Motor must operate with in specified RPM/Torque ranges Uncontrolled Motor behavior Loss of torque 8 Inverter electronic malfunction 2 NoneCAN messages / Motor RPM monitoring Inverter: Inverter pack must operate within specified temperature range Inverter over temperature Inverter unable to supply motor with adequate power 7 Temp sensor malfunction/ coolant leak/ inverter malfunction 7 Proper hose/ fitting selector/ respond to increase in temp. before undesirable operation happens Detect pump impeller speed / monitor and verify temp/ monitor inverter temperature 298

Test and Review

References “A Guide to Electric Drives and DC Motor Control, Published by Ohio Electric Motors,” electric-drives-and-dc-motor-control-688#ixzz2t4v60h6B, Aug Boglietti, G. Griva, Pastorelli, M., Profumo, F., and Adam, T., “Different PWM Modulation Techniques Indexes Performance Evaluation,” IEEE Technical Paper, , Hughes, Austin, and Bill Drury, “Electric Motors and Drives: Fundamentals, Types and Applications,” Oxford: Newnes, , , Kumar, R. R., Kumar, S., and Yadav, A., “Comparison of PWM Techniques and Inverter Performance,” IOSR-JEEE, ISSN: , Volume 4, Issue 1, PP 18-22, Jan. - Feb “Motor Drive & Control,”