New Capabilities on Hybrid & Electric Drives

Transcription

1 New Capabilities on Hybrid & Electric Drives Available TODAY Barry James Chief Technical Officer September 2015

2 Contents R&D Themes New capabilities available today in Hybrid and Electric Vehicles o o o NVH Efficiency Thermal Summary Slide 2

3 R&D Themes and Collaborators Energy Efficiency Dynamics Component Models Slide 3 Engineering Processes

4 Example encountered by Mercedes Benz: System interaction between motor and gearbox is critical Slide 4

5 Slide 5

6 (Software) Known: Gear whine: Response of the gearbox system to transmission error Calculation of the excitation from gears (transmission error) New: Gear and motor whine: Response of the gearbox and motor system to transmission error and motor excitation Calculation of the excitation from gears (transmission error) and motor (torque ripple, imbalance and radial force shapes) Slide 6

7 New: Gear and motor whine: Calculation of the excitation from gears (transmission error) and motor (torque ripple, imbalance and radial force shapes) Future: Motor noise Calculation of motor excitation for various motors (IM, PM, SRM), implemented in software Feasibility, concept, detailed calculations Applied force shape Stator response Slide 7

8 Software Known: System static analysis: Deflection of the shaft/bearing/ housing system due to mechanical loads (e.g. gear loads) New: System static analysis: Deflection of the shaft/bearing/ housing system due to mechanical loads (e.g. gear loads) and unbalanced magnetic pull Air gap calculation due to deflections, dynamic effects etc. Motor stator Air gap Motor rotor Gearbox housing Slide 8

9 Software Known: System dynamic analysis: Identifying why there is a noise problem once the system has been designed and built New: System dynamic analysis: Identifying and avoiding a noise problem early in the design process Slide 9

10 Software Known: System dynamic analysis: System dynamics for gear whine and audible noise New: System dynamic analysis: System dynamics for vehicle dynamics, driveability and passenger comfort Link to control systems for vehicle launch Slide 10

11 All Vibrations Non-linearity Transient shocks Gear Rattle Bearing skidding, cage effects Tip-in/Tip-out Gear shift quality YOUR DYNAMIC PROBLEM Motor Unbalanced Magnetic Pull Drive cycles Vehicle launch Electro-mechanical with control High speed shafts Powertrain bending Imbalance Bearing/Pump/Gear/Motor noise Frequency Slide 11

12 Known: Powertrain efficiency: Calculate efficiency for a given drive cycle (e.g. NEDC) New: Powertrain efficiency: Assess robustness of fuel economy against driving conditions at the concept stage Select the most robust design Assess efficiency against collections of drivers/ locations/ journey types Slide 12

13 Known: Powertrain thermal build up: None assume a given temperature for the gearbox New: Powertrain thermal build up: Analysis of heat dissipation from motor fins Analysis of transient thermal build up of whole powertrain Transient heat flow from motor to gearbox (v) l d Slide 13

14 Known: Trade-off between cooling and noise performance: None we ignore the cooling New: Trade-off between cooling and noise performance: A matrix of designs assessed to find the optimum design Slide 14

15 Known: Drive cycle simulation from start up: Assume a constant temperature Ignore interactions between temperature rise, oil viscosity, powertrain efficiency New: Drive cycle simulation from start up: Multi-physical simulation of the system with all influences linked (oil properties, thermal transient, tooth contact, EHL, system deflections, surface roughness) Slide 15

16 Summary Software Romax is involved in a wide range of innovative R&D focussed on improving driveline engineering When applied to EV and HEV, it forms a coherent and unique offering to the marketplace Available as software or consultancy NOW More is coming! Slide 16

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