Pontus Fyhr

A modular framework for evaluation of electrical machine production costs

A framework structure for solving multiple option production economic models is described, showing the possibilities in defining independent process modules according to a defined set of rules. The modules are then scanned and inserted into appropriate locations in the solver framework based on naming scheme and linking information, allowing both re-use of knowledge as well as rapid development and deployment of models for new production. The methodology is applied to the production of an electric machine, showing the ability to assess options with regard to for example technical infeasibilities such as the combination of incompatible production method selections, splitting and joining process flows and maintaining a continuous solution space. The structured framework approach also allows extraction of data from any point in the production flow, for any option or nominal batch size.

The scale of permanent magnet materials for automotive traction motors

A mathematical model is developed with the purpose of estimating the scale of permanent magnet materials consumption in hybrid and electric automotive traction systems. These estimations are compared to consumption figures from industries such as wind power, HVAC, consumer electronics and industrial machinery. The estimations generated are useful in strategic decision-making for production planning.

Scalable performance, efficiency and thermal models for electric drive components used in powertrain simulation and optimization

A methodology for designing and scaling the performance and thermal characteristics of electric powertrain components is presented. This methodology is aimed at finding optimum component combinations based on a set of requirements. Both drive-cycle performance and specific operating modes such as curb-climbing and maximum wheel speed are considered. This allows the selection of electrical machine topology, the design and sizing of the related gearbox, as well as the power-electronic converter needed to fulfill the wheel torque and speed requirements for all operating points, including overloading. Utilizing subsystem-models inside an optimization loop, the powertrain components can be sized using a number of goals such as lowest cost, size, weight or combinations of these, while still fulfilling the target specifications for a number of powertrain layouts.

Performance and manufacturability tradeoffs of different electrical machine designs

This work addresses the manufacturability challenges in traction machine production systems and design. The tradeoffs between performance and manufacturability of a heavy duty traction machine for buses and trucks, are investigated for four different winding designs, with multiple stator combinations, all using the same interior permanent magnet rotor. We present an analysis of electromagnetic, thermal, cost and production system performance for 6 primary combinations.

Electric roads: Reducing the societal cost of automotive electrification

In this article five scenarios for fully electric road transport in Sweden are compared, looking at the total system cost for different combinations of battery systems, vehicle equipment and charging solutions, including the use of Electric Road Systems (ERS). The main objective of this work is not to provide accurate price estimations, but to help understanding the main cost drivers of transport electrification and to illustrate how the final system cost is influenced by the different parameters considered. The main conclusion obtained is that, despite the substantial initial investments required for the deployment of electric roads, a system featuring only static charging and vehicles with large size batteries results in a higher total system cost. Moreover, due to the much larger number of light duty vehicles in the fleet, the deployment of an ERS system that can be used by both long-haul and light duty vehicles is substantially more advantageous than a solution restricted only to long-haul vehicles.

Statistical interfaces for production of a permanent magnet based rotor

A production-system simulation model for manufacturing cost of a permanent-magnet based rotor, analyzing the influence of uncertain parameters by utilizing the Monte Carlo method. The uncertain parameters studied include investment and bill of materials costs as well as cycle time. The resulting influence of these uncertainties are presented for each case individually, as well as all possible combinations, giving seven total cases studied. Cutting tool costs over a range of batch sizes show that investment uncertainty has rapidly declining impact even within fairly low batch sizes. BOM cost variations, especially for the permanent magnets maintain a sizeable influence over the range of batch sizes. The Weibull distribution based model for permanent magnet insertion shows that profit margins derived from point based nominal data is not reliable for pricing of manual production processes. The presented approach is useful both for decision making regarding new production, as well as pricing in competitive markets with narrow margins.

Optimization of Electric Powertrains Based on Scalable Cost and Performance Models

This work presents a methodology for modeling, designing, and scaling the electromagnetic, mechanical, and thermal characteristics of the main components in an electric powertrain (excluding the battery), i.e., a power electronics converter, an electrical machine, and mechanical transmission. Additionally, a framework for estimating the cost of these components is described. This framework takes into consideration not only the material cost, but also all major manufacturing steps required for the production of a component and their dependence on expected production volumes. Moreover, a procedure to optimize the design of an electric powertrain, taking advantage of the aforementioned models, is proposed. Finally, the powertrain for a passenger electric vehicle is optimized using the proposed methodology, and the results are compared in terms of the electrical machine topology, powertrain concepts, cost, weight, gear ratio(s) in the transmission, and overloading capabilities.