Testing Next-Generation Inverters for Vehicle Traction Applications

Dynamometer Overview:

Presentation Outline NCREPT Overview

Dynamometer

Overview

Subsystems

Driving Schedules

NCREPT’s Mission & FocusBackground:

NCREPT was formed in 2005 as a result of the 2003 Northeast Blackout and began investigating advanced power electronic solutions for the grid and transportation applications.

Research Focus:

Design and test advanced, solid-state solutions applicable to:

Control technologies with a focus on grid reliability (e.g., Fault Current Limiter) Power interface applications that allow diversification of power sources to the grid (e.g.,

Smart Green Power Node) Transportation (automotive, aerospace, traction) and other extreme-temperature

power electronics applications “under the hood” (e.g., SiC Battery Charger, SiC Inverter) Energy exploration and geo-thermal applications (down-hole electronics)

Associated Centers GRid-connected Advanced Power Electronics Systems (GRAPES)

http://grapes.uark.edu/

Power Optimization of Electro-Thermal Systems (POETS)

https://poets-erc.org/

Cybersecurity Center for Secure Evolvable Energy Delivery Systems (SEEDS)

https://seedscenter.uark.edu/

Prototype Test & Evaluation Facility 7000 square foot building

$5 million facility

Cost-effective facility for businesses, national labs, and universities

Pay-Per-Use Structure

First user arrived in Feb. 2009

IEEE 1547 and UL 1741 standards testing

Expanding to approximately 14000 square feet

NCREPT Control Room

NCREPT Bay Area

NCREPT One-line Configuration

Examples of Previous Testing

Research Successes R&D 100 (2009)SiC Power Modules (actual photos)

Collaboration with APEI, Rohm, Sandia Built and tested R&D 100 Award Winner (2009)

MMC Baseplate

DBA Power Board

LTCC Driver Boards

Research Successes R&D 100 (2014)SiC-Based Battery Charger

Collaboration with APEI, TRI, ORNL, CREE, ARPA-E 10x Increase in Power Density! R&D 100 Award Winner (2014)

Research Successes R&D 100 (2016)SiC-Based Traction Drive

Collaboration with APEI, TRINA, NREL, GaN Systems 55 kW Operation; 140°C Ambient; 105°C Coolant R&D 100 Award Winner (2016)

Dyno One-line Configuration

SPARE

Utility Input

12.47kV – 480V

UM1MDSC32 480VMSB1

HP1

Building Load

F1MDSC16

F4MDSC32

480V

F8MDSC32

MV3150 VCP-W500 13.8kV

13.8kV

480V

MV2

HP2

750 kVAVVVF

EUT3 EUT4

MV1

F2MDSC16

F3MDSC32

F7MDSC08

F5MDSC20

F6MDSC20

F9MDSC32

F10MDSC32

F11MDSC32

F18MDSC32

F12MDSC32

F13MDSC32

F14MDSC32

F17MDSC32

F16MDSC32

F15MDSC32

MV2150 VCP-W500

MV1150 VCP-W500

MV5150 VCP-W500

MV4150 VCP-W500

MV6150 VCP-W500

MV7150 VCP-W500

MV8150 VCP-W500

MV9150 VCP-W500

MV10150 VCP-W500

MV12150 VCP-W500

MV11150 VCP-W500

SPARE

MV14

REGEN2

2 MVA

REGEN3

2 MVA

REGEN1

2 MVA

A

B

A

B

A

B

A

B

A

B

A

B

A

B

A

B

Auxiliary source

T1 T2 T3

T6

VVVF-DS

MV13150 VCP-W500

T4T5

Torq

ue

Tr

an

sdu

cer

Dynamometer Overview

Logical Teststand Diagram

Dynamometer Thermal Additions Thermal

Additions 10-ton Chiller

Heat Exchanger

105°C cooling loop

Thermal Chamber -75°C to 175°C

600L Capacity

National Instruments DAQ

Dynamometer Frame and Couplers

Centralized Control and Data Acquisition Remote Control

ABB Drive (Modbus TCP)

700kW Supply (Modbus TCP)

SiC Drive (CANbus)

Data Acquisition

National Instruments Hardware

Voltage Sensors

Current Sensors

Temperature Sensors

Cooling Loop

Flowrate

Torque/Speed Transducers

Yokogawa Power Analyzer

Internal Controller Parameters

ABB/Unit Under Test

Automated Test Sequences

Driving Schedules Provide a realistic driving profile that simulates road

driving conditions in different environments

User has a choice of driving schedules and specifies the vehicle model to calculate the torque required for the vehicle to achieve the requested speed

Dynamic models of various vehicles

Modeling of external elements e.g. headwinds, grade, road conditions

Modeling of Vehicle Dynamics

Equation describing the forces that act on the vehicle body is the basis for most vehicle simulation programs:

Input variables the user can easily edit:

𝐹 = 𝑚𝑔𝐶𝑟𝑟 +1

2𝜌𝐶𝐷𝐴𝑣

2 +𝑚𝑎 +𝑚𝑔𝑠𝑖𝑛 𝜃

Force required to overcome rolling resistance

Drag force that must be overcome to reach the requested speed from the driving cycle

Mass inertia of vehicle

Force required to propel vehicle on non-zero grade

m Mass of vehicle

Crr Coefficient of rolling resistance

CD Aerodynamic drag coefficient

A Frontal surface area of the vehicle

v Vehicle velocity (obtained from driving schedule)

a Vehicle acceleration (obtained from driving schedule)

θ Angle of road incline

Simscape Driveline Modeling

Driving Schedules and Torques Torque/Speeds at motor shafts calculated using vehicle models using Simscape Driveline™

Compared with discontinued Advisor (NREL) software [reduced time-step]

- Matlab Program- NREL’s Advisor

To

rqu

e (N

m)

Driving Schedules and Torques OPAL-RT system is used to generate dynamic, fast changing torque and speed

values based on the EPA driving schedule selected.

The speed and torque commands from the simulator are sent to the LABVIEW interface using Modbus TCP

Spee

d [

rpm

]

Simulated Torque Values from Simscape/OPAL-RT Actual Testing Results showing Torques and Speeds from Dyno

THANK YOU

Questions?