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This paper presents advanced and cost-reducing technologies of a motor drive system with reduced permanent magnets but without a position sensor. The key enabler is the integration of novel designs of flux-intensifying interior permanent magnet synchronous machines (FI-IPMSMs) and position self-sensing control technologies. In this paper, we focus on two advantages of FI-IPMSM over conventional flux-weakening interior permanent magnet synchronous machines (FW-IPMSMs). The first benefit is that thinner magnets are possible and there is less concern for demagnetization because of its significantly smaller flux-weakening current. This paper presents two design examples of FI-IPMSMs, one of which has not only smaller magnets but also similar power conversion capability. The second advantage is reduced saturation and cross-saturation effect, which leads to improved position self-sensing capability.

To make electrical or electro-hydraulic gas exchange valve actuators more economically feasible for the production of cam-less engines, it is desirable to achieve valve position information from existing engine sensors rather than to develop and install new sensors for each gas exchange valve. Time and frequency domain characteristics of acoustic (knock) sensor signals were analyzed using both cross-correlation and Fourier analyses to determine characteristics that indicate valve position. The time-domain signatures for valve events were found to be inconsistent from cycle to cycle and thus difficult to identify using cross-correlation techniques. Frequency content of the engine vibration as it varied with crankshaft angle was analyzed to find valve position dependent patterns. Analysis revealed a wideband signal that correlates to intake and exhaust valve closing events.

A 4-wheel drive off-road vehicle was designed and fabricated using extensive hydraulic technology for the SAE (Society of Automotive Engineers) Mini-Baja competition. The vehicle incorporates an open hydrostatic transmission using a single pump and four independent drive motors. A constant power controller that maintains full engine power to drive the vehicle or stores excess energy in two accumulators controls the pump. Each of the drive motors is independently controlled using a proportional meter-out pressure control valve. The use of pressure control allows the flow to each of the motors to be proportioned based on the dynamics of the vehicle. A CAN bus controller is used in conjunction with a steering sensor to provide differential motor speed control in maneuvering conditions that insures 4-wheel drive availability at all times. Steering of the vehicle is achieved by articulating the chassis using a rotary actuator and multi-motion actuator controlled by the driver.

Micro-machined planar orifice nozzles have been developed and used with commercially produced diesel injection systems. Such a system may have the capability to improve the spray characteristics in DI diesel engines. The availability of a MEMS (Micro-Electro-Mechanical-Systems) processing sequence supported the construction of micro-planar orifice nozzles, and micro-systems technology was also employed in our macro-instrumentation. To demonstrate this process, fourteen MEMS nozzles were fabricated with deep X-ray lithography and electroplating technology. The circular orifice diameters were varied from 40 to 260 microns and the number of orifices varied from one to 169. Three plates with non-circular orifices were also fabricated to examine the effect of orifice shape on spray characteristics. These nozzles were then attached to commercial injectors and the associated injection systems were used for the spray experiments.

We have developed and used micro-machined injector nozzles with commercially produced diesel injection systems that have the capability to improve the spray characteristics in DI diesel engines. The availability of a MEMS (Micro-Electro-Mechanical-Systems) processing sequence supported the construction of micro-diesel injector nozzles, and micro-systems technology was also employed in our macro-instrumentation. Fourteen different circular plates (nickel-iron alloy) were fabricated with deep X-ray lithography and electroplating technology. Five plates that have a single orifice were fabricated to investigate the effect of orifice diameter on spray characteristics; i.e., 40 to 260 microns. The spacing between multiple orifices was also varied; e.g., two plates that each had 41 orifices and 169 orifices, respectively, with a diameter of 40 microns. Finally, three plates with non-circular orifices were also made to examine the effect of orifice shape on spray characteristics.

The effect of wall temperature on single surface flame quenching and flame structure of an atmospheric premixed methane-air flame was studied. The luminous region of a laminar flame was located at an angle of 45 degrees to a temperature- controlled surface. C2 laser-induced fluorescence was used as an indicator of flame position while Raman spectroscopy was used to determine gas temperature profiles near the surface. These measurements were conducted for wall positions (vertical distance from the surface) ranging from 50 mm to 1.0 mm and wall temperatures ranging from 150 °C to 600 °C. C2 laser-induced fluorescence measurements indicated flame position is affected by the presence of a surface and the surface temperature. Larger C2 fluorescence intensity values were observed for higher wall temperatures at all distances from the surface.