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This paper introduces a newly developed Power Electronic Inverter library in Modelica. The library has different levels of complexity to approximate the power losses in the power inverter. In addition, it provides two different modelling domains (ABC and DQ). The library utilizes a multi-level approach with increasing model complexity, each model is interchangeable in the system including power inverter, controller and machine. There are two attributes which are implemented into this library. First, the model calculates the electric behaviour of the power semiconductors, i.e. IGBTs, MOSFETs and diodes including the thermal effects. This can be fully parameterized based on the characteristic curves and parameters specified in the manufacturer’s datasheet. Secondly, the analytical approach of power losses approximation based on the datasheet. It is interchangeable between two reference frames (ABC and DQ). The model is then validated with PLECS simulation to confirm the accuracy.

An integrated, online fouling monitoring technique that provides dynamic and real-time information of membrane fouling during a water treatment membrane process was developed. This technique has preliminarily been demonstrated for monitoring particulate fouling in a water treatment microfiltration process using a single photo sensor. The results of the online dynamic analysis suggest that this technique provides in situ measurement of fouling layer thickness, dynamic analysis of the fouling layer structure, and monitoring of water quality during the membrane filtration process.

The medical examination is a crucial step among medical behaviours. To guarantee the quality of examination, inventory management of reagents and consumables is also a requiring groundwork, besides keeping the proper function of examining works. However, it is difficult for the staff to effectively manage reagents of various categories and complex packages. The laboratory we cooperated has no any forecasting and decision support system, purchasing is totally based on personal experience of purchasers. When newcomer is in charge of purchasing, the exceeding purchasing results in hoard and overdue reagents or the omission of the fluctuating usage of specific reagents results in deficiency and standstill of the work which are commonly situations appeared. Thus we are combing the forecasting model developed by scholars Liao Yueh Hsiang et al. to calculate the demand of each reagent.

The growing demands for electrical capacity on future more electric aircraft (MEA) has led the engine-based generators to increase in size. Many manufacturers and researchers have a strong interest in developing fuel cells for aerospace applications due to their advantage of high efficiency and their use as a medium for clean energy resources. A particular interest is in using fuel cells within the Auxiliary Power Unit (APU) - a function that is currently provided by an additional gas turbine in most aircraft. Their integration into aircraft systems is not straightforward. A particular challenge, which this thesis addresses, is the provision of a suitable power conversion system which is able to interface the fuel cell to the aircraft electrical system – taking account of the complex electrical characteristics of the fuel cell and the demanding requirements of the aircraft electrical network. \ud \ud The interleaved boost converter with coupled inductors (IBCI) is one of the many converters that is promising for fuel cell applications because it has low input current ripple and a high step-up voltage gain. It comprises a current doubler circuit, voltage doubler rectifier, coupled inductor and active clamp. The proposed converter is an extended version of the single phase to multiphase IBCI converter using interleaving techniques. The input stage of the converter is a coupled inductor which connected to a half-bridge configuration and an active clamp. The output side is a voltage doubler rectifier. A detailed analysis of the converter and associated modelling are presented. The design and construction of a prototype converter is presented with a particular focus on ensuring operability of the converter over the entire fuel cell characteristic range as well as achieving high efficiency at nominal load. A laboratory-scale (1/10) prototype of a nominal full-scale converter was built to verify the feasibility of the proposed converter topology. Good agreement between the experimental results and the simulation results has been demonstrated, which validates the converter design, modelling, and effectiveness of the efficiency evaluation approximations.