Yasushi Onoe

Application of Tracking Simulator to Reforming Process

We are researching advanced operation support system which can help operators and provide them with novel knowledge. Advanced operation support system needs more essential information of plants such as temperature of reactor inside, real-time data of composition, prediction of the process behavior and so on. We use simulators as a way of getting such essential information of plants from the experience that we have developed process simulator. Our process simulator is strictly based on chemical engineering principle, namely, rigorous model which makes accurate simulation possible. However, it is hard to keep simulation highly-accurate against many reasons, e.g., change of process characteristics with degradation of plant equipments or catalysts. For this reason, we have proposed tracking simulator which runs in parallel with an actual process and adjust its parameters online. We developed an experimental steam reforming plant generating hydrogen from methane gas and the corresponding model for demonstration of tracking simulator. And then, we run tracking simulator with the process to visualize composition of reactor in real-time as an example of operation support

MODEL PARAMETER ESTIMATION BY TRACKING SIMULATOR FOR THE INNOVATION OF PLANT OPERATION

Abstract This paper proposes a new application of the tracking simulator relevant to future plant operation. The tracking simulation technique will enable matching of physical and virtual worlds. The simulator receives sensor data from the plant and the model parameters in the simulator are constantly adjusted to match the actual plant behavior. Model parameter estimation is one application of the tracking simulator. Here, the tracking simulator showed good simulation accuracy with model parameters to estimate the functions of its related variables. A fuel cell simulator was used for model parameter estimation in this study.

An Application of On-Line Tracking Simulator to a PEMFC

The polymer electrolyte membrane fuel cell (PEMFC) presents number of control problems due to its complex dynamics. Water management is known to be one of the critical issues for efficient operation of the PEMFC. But water transport process inside PEMFC is a complex phenomenon, making it hard to predict output voltage at highly humidified condition by use of off-line simulator. Recently physical model-based controls of PEMFC are proposed to achieve efficient operation of PEMFC. However to realize the model-based control of PEMFC at high energy regions, the construction of high precision, high speed dynamical simulator with water process model becomes indispensable. We have developed an on-line tracking simulator, simultaneously running with actual process to adjust model parameter of the simulator to the actual process in real-time. By applying on-line tracking simulator to PEMFC experiment, we have performed an experimental study of on-line tracking simulator to a PEMFC. The experimental study validated the use of on-line tracking simulator to predict accurately the output voltage of PEMFC even at highly humidified condition where uncertain liquid water processes becomes apparent

Antenna-coupled rectifying diode for IR detection

An antenna-coupled rectifying SChottky Barrier DIode (SBD) for IR detection is fabricated on Si by IC processes. Aluminum thin film antenna of 30 micrometers length and 1.5 micrometers width is formed on thermally grown SiO2 layer on Si. At the end of antenna, rectifying SBD of 0.03 micrometers diameter is formed by focused ion beam (FIB) milling technique. Ion current monitoring system with FIB largely reduced the size of milled hole, which is conventionally limited by ion beam waist diameter. IR radiation from CO2 laser of 10.6 micrometers in wavelength and 0.55 W in power is used for device evaluations. Signal dependence on incident angle of CO2 laser radiation and dependence on diode bias voltage are evaluated. We confirmed the rectifying operation of antenna- coupled SBD at IR region and experimentally obtained rectified voltage of 173 nV. The NEP is calculated to be 1.94 X 10-6 W/Hz-1/2.

Parameter estimation of PEMFC by on-Line tracking simulator

The tracking simulator receives the sensor-measured data directly from the plant and the model parameters inside the simulator are adjusted in order that the output of simulator agrees with data from the plant. Therefore its possible to estimate the simulation model parameters which changes with an elapse of time and operational status by the tracking simulator. We report that more precise simulation can be done to the fuel cell by utilizing the tracking simulator.

Probe-type microforce sensor for microactuators

In recent years with the development of MEMS, various microactuators have been developed. In general, the smaller the actuator, the smaller its force becomes, but measurement of such small force is difficult and dependable instruments are not currently available. We developed a probe type sensor to measure very small forces using a semiconductor shear strain gauge of a cantilever type sensor. A highly sensitive, stable probe was created by using a good raw material, single crystal silicon, and by forming both the stress concentration part and the strain sensor on the same silicon crystal. We designed the probe using the finite element method, and invented a structure in which a very small force effectively generates strain on the sensor. We also developed a semiconductor micromachining process including an inducted coupled plasma deep trench etching method to manufacture the probe, and built a calibrator for the probe based on an electronic balance. In preliminary experiments, we successfully measured the force with as small as 1 mN resolution, precisely as designed by FEM. In future, we shall develop a probe with 1 (mu) N resolution.