Transcript Slide 1
SRMs in HEV applications Comparison of electrical machines for HEVs SRMs in HEV applications Wheel loader It weighs over 180 tones 21m³ rock bucket handles a 38 tone payload 141:1 planetary gearbox 300kW / motor 20,000 hours life for the bearings SRMs in HEV applications Hybrid bus drive 2x SR drives (50kW and 160kW) One combustion engine (2.5L Di) Low loss Li-Pol battery No gearbox CO2 emissions lower with 40% Fuel consumption lower with 30% SRMs in HEV applications SR drive variator system for Renaul TIVA The two SRMs are not in line any more The gearbox is excluded Infinite gear steps are obtained The SRMs have 25kW Speed range from 1800rpm to 11000rpm Maximum torque of 135Nm Diameter: 192mm Active length: 160mm Voltage: 425V SRMs in HEV applications Starter alternator unit for trucks Power: 30kW Voltage: 340V Torque: 1200Nm SRMs in HEV applications Starter alternator technology: 65Nm torque, 2kW power 3kW power in generator regime Sensorless position control Inverter based on MOSFET tech. AC Induction Brushless DC Switched Reluctance AC Induction Source: “AC, Brushless, Switched Reluctance Motor Comparisons” James R. Hendershot, Magna Physics Corporation Brushless DC Source: “AC, Brushless, Switched Reluctance Motor Comparisons” James R. Hendershot, Magna Physics Corporation Switched Reluctance Source: “AC, Brushless, Switched Reluctance Motor Comparisons” James R. Hendershot, Magna Physics Corporation Source: “AC, Brushless, Switched Reluctance Motor Comparisons” James R. Hendershot, Magna Physics Corporation Motor Comparison for BEVs & HEVs PMBDC IM SRM Brushed DC Speed [rpm] 1000 1000 1000 1000 Torque [Nm] 2866 2866 2866 2866 Max. Speed [Nm] 4000 4000 4000 4000 Torque [Nm] 716 716 716 716 Voltage [V] 380 380 190/300 500 Current [A] 753-486 980-630 1000/500 520 Frequency [Hz] 156 133 500 133 Weight [kg] 300 600 500 1000 Power [kW] 300 300 300 300 Efficiency % @1000 rpm @4000 rpm 95 97 93 95 94 96 85 89 Cooling Oil Oil Oil Air Source: Lightweight Electric/ Hybrid Vehicle Design Ron Hodkinson and John Fenton In Summary Due to the absence of rotor windings, SRM is very simple to construct, has a low inertia and allows an extremely high-speed operation. SRM operates in constant torque from zero speed up to the rated speed. Above rated speed up to a certain speed, the operation is in constant power. The range of this constant power operation depends on the motor design and its control. The brushless DC/AC has the benefit of embedded energy source, high torque densities and high speed rage. Already implemented on the Toyota Prius and Toyota SUV proved to have a good behavior in HEVs The induction machines are a candidate in the fields of HEVs too. Them manufacture already reached a lot of experience during time and several optimization research activities were performed to push the limits of them performances. Studies proved that using them “in wheel”, like in the case of Audi E-Tron reached the request of fast and easy to control HEV. Thank you for your attention !