Browsing by Author "Marco, James"

Now showing 1 - 3 of 3
  • Thumbnail Image
    ItemOpen Access
    A classical control approach to the power management of an all-electric hybrid vehicle.
    (2009-01-01T00:00:00Z) Marco, James; Vaughan, Nicholas D.
    Modern hybrid electric vehicles (HEVs) often employ all-electric powertrains that utilise hybrid sources of power and energy; such as batteries, fuel cells and ultracapacitors. This paper describes the design, simulation and experimental verification of a power management control system that manages a high voltage battery, a DC-DC boost converter and an ultracapacitor within a front-wheel drive HEV in which the motive power for the vehicle comes from two electrical machines. As part of this study, consideration is given to the complete control system design life-cycle including plant model development, algorithm design and software implementation on the target electronic control unit (ECU). Off-line simulation and initial experimental results are presented showing the vehicle operating on a powertrain dynamometer as one means of demonstrating the ability of the ultracapacitor to limit the transient demands placed on the battery during periods of vehicle acceleration and regenerative braking.
  • Thumbnail Image
    ItemOpen Access
    Design of a reference control architecture for the energy management of electric vehicles
    (Inderscience, 2012-12-31T00:00:00Z) Marco, James; Vaughan, Nicholas D.
    The High-Voltage (HV) network within an Electric Vehicle (EV) will typically comprise different energy sources such as fuel cells, batteries and ultracapacitors integrated together through the use of both unidirectional and bidirectional DC-DC converters. Given the multitude of feasible HV network designs, there are obvious advantages in having a unifying control architecture that facilitates the Energy Management (EM) control task. Within this paper, a control Reference Architecture (RA) is proposed that can be employed as a template for the design of the EM control function. Example EM control systems are presented each derived from the same RA, but relating to a different physical configuration of HV network. Simulation results are presented to verify the functional performance of the control systems. In each case, the design trade-offs associated with the functional performance of the EM strategy and the non-functional requirements of modularity and reusability are discussed.
  • Thumbnail Image
    ItemOpen Access
    Feasibility of High-Frequency Alternating Current Power for Motor Auxiliary Loads in Vehicles
    (IEEE Institute of Electrical and Electronics, 2011-02-02T00:00:00Z) Antaloae, C. C.; Marco, James; Vaughan, Nicholas D.
    This paper presents a feasibility study into the application of a 100-V, 50-kHz high-frequency ac (HFAC) network for powering automotive electrical auxiliaries. The study is focused on motor-actuated loads and is divided into two sections. First, the investigation indicates the benefits of replacing low-torque dc motors with lighter and more efficient 400-Hz ac machines for applications such as electric fans, fuel pumps, or blower motors. A comparative examination of commercially available machines indicates space and weight reduction of more than 60%, and efficiency savings between 25% and 100% are possible. Second, the inquiry evaluates the viability of replacing existing dc/ac inverters with HFAC/ ac converters for high-torque ac machines as employed, for example, in electric- power-assisted steering (EPAS) or heating, ventilation, and air conditioning systems. Based on experimental and simulation results for a column-assist EPAS application employing a three-phase permanent-magnet synchronous motor, this paper shows that an HFAC drive is expected to reduce the voltage harmonic content below 50 kHz by at least 10% compared with the dc/ac inverter. However, the disadvantages of the former drive make it less attractive than the existing dc/ac circuit. Specifically, the EPAS motor torque ripple is expected to be approximately 2% higher compared with the dc counterpart drive. Further drawbacks of the HFAC/ac drive include high metal-oxide-semiconductor field- effect transistor (MOSFET) conduction losses, higher voltage harmonics above 50 kHz, and complex control requirements of the inverter. Conclusively, significant HFAC advantages for motor loads can only be attributed to machines with a nominal torque capability that is limited to 2 N ·m. However, given the number of such devices within a typical vehicle, this translates into a possible vehicle mass saving of 30 kg and a potential reduction in fuel consumption by 0.8 L/100 km