Specifications and Design of a PM Electric Variable Transmission for Toyota Prius II

Abstract

This paper focuses on an analysis of technical requirements for the design of a permanent magnet type electric variable transmission (PM-EVT), which is a novel series-parallel hybrid electric vehicle (HEV) powertrain concept. Similar to the planetary gear train used in the Toyota Prius II, the EVT also realizes the power split function. However, it is implemented in an electromagnetic way rather than in a mechanical way, as is the case for the Prius II with a planetary gear. In this paper, a procedure to define the technical requirements of an EVT is presented. Since the Toyota Prius II is a well-known series-parallel HEV, this vehicle is chosen as a reference. The engine, the battery and other necessary components are kept as input data. A dynamic simulation was performed in order to take into account different driving cycles. Then, based on an analysis of the simulation results (torque, speed and power) the technical requirements of the PM-EVT are defined. Finally, the PMEVT machine is designed. The PM-EVT design results are presented and validated using the finite element method. Author Keywords: Electric variable transmission , Permanent magnet machine , Planetary gear , Series-parallel HEV

Field-Oriented Control for an Induction-Machine-Based Electrical Variable Transmission

“…Further E 1 depends linearly on the speed of the inter-rotor, while E 3 depends linearly on the difference in speed of inter-rotor and rotor as can be seen in (25) and (26) respectively. At the terminals of the machine the resistive voltage drop over the windings is added to the induced voltage as can be seen in equations (1) and (3). This resistive part is mainly of interest when the torque is high or the flux level of the machine is low since then high currents are demanded.…”

“…A power split device is required to split the power to the wheels in a part directly coming from the combustion engine and a part exchanged with the battery. This task is nowadays performed through a mechanical planetary gear [3], [4], for which two electric motor/generators are needed, each connected to a different shaft of the gear. The remaining shaft is connected to the combustion engine.…”

Field Weakening Control of a PM Electric Variable Transmission for HEV

“…The inner rotor is connected to the shaft of the internal combustion engine (ICE), and the outer rotor to the final drive gear. Such a PM-EVT has been designed [22] based on the technical specifications of Toyota Prius II [30][31][32]. The main parameters are given in Table 1.…”

“…A dynamical control using field weakening for a single machine is studied in [21], but no detail is given on the field weakening algorithm and no dynamical results are provided. In order to compare the EVT-based solution with a planetary-gear train solution, a PM-EVT has been specifically designed for Toyota Prius II [22,23]. A first control scheme has been defined for this new series-parallel HEV using EMR (Energetic Macroscopic Representation) [24].…”

Parasitic Resistance Analysis in a Novel High Step-Up Interleaved Converter for Hybrid Electric Vehicles

“…Nowadays, Hybrid Electric Vehicles (HEVs) are usually manufactured with high-voltage and high-energy battery packs in order to store the required energy to supply the enough torque and the speed needed in the daily needs of the users [1]- [5]. At the same time, a high-capacity battery storage system tends to be degraded during its shelf life by the time and the cycling.…”