Holonic Manufacturing Systems (HMSs) are regarded as a foundation of cyber-physical production systems as they enable computers to conduct intelligent process planning, scheduling, and control by endowing manufacturing components with autonomy and collaboration. In an HMS, autonomy is realized by specifying holons that represent virtual agents of manufacturing components, while collaboration is facilitated through a communication mechanism that enables data exchange and decision making throughout a holarchy of holons without human intervention. This study presents the development of a virtualized holon model and a predictive process planning procedure using the Asset Administration Shell (AAS), i.e., a standardized model that can identify digital representation of manufacturing components to ensure interoperability. Specifically, an AAS-based information model was proposed to define operator, machine, product, and order holons. In addition, a predictive process planning procedure based on the Contract Net Protocol was developed to automatically allocate tasks while predicting task execution times. This study can contribute to the designing of an AAS- domain specific information model for HMS to increase interoperability in the holon holarchy, exhibiting the feasibility of AAS applications in predictive process planning on HMS.

Power electronic systems have been widely applied in both industrial and domestic applications in the modern society for controlling and converting electrical energy. Due to their characteristics, such as excellent performance, low cost, high reliability, and low weight and size, power semiconductors, including insulated-gate bipolar transistors (IGBTs) dominate the market of power converters. The technical progress and development trend of IGBT for industrial applications are primarily driven by five aspects influenced by each other to an extent, including operating temperature, efficiency, dimension, reliability, and cost. Liquid cooling systems surpass the air cooling systems by supplying heat transfer coefficient, which is several orders of magnitude higher. Thus, using liquid cooling system enables much higher power densities of power modules and more compact converter solutions.

The high voltage direct current (HVDC) device has been used to transmit electrical power with an advanced technology of semiconductors. The sustainable energy generation technologies of solar power and windmills are demanding that the HVDCs have high performance and reliability. In this regard, the cooling performance of the HVDC becomes a significant research topic because the temperature increase affects the operation of the device. The evaluation system to assess the cooling performance has been developed and is proposed in this paper. The experimental apparatus is presented in detail. Our experiments have shown the accuracy of flow rates, pressure drops, and the temperatures in the desired measurement points. We have successfully developed an evaluation system of the cooling performance of the HVDC device which has 2.48 kW of heat dissipation.

It has been an on-going issue to develop a high voltage motor with high capacity and reliability. In this study, we investigated the effective coil insulator materials in terms of thermal conductivity. To quantify the contribution of the coil insulator material, two different motors with and without the cooling structure were numerically studied. Based on the measured thermal conductivity of six different coil insulators, we have achieved the effectiveness of thermal conductivity. Consequently, the high voltage motor can be developed with the proposed effectiveness of thermal conductivity regarding coil insulator materials. Our study of fundamental material characteristics will be beneficial in enhancing thermal management technology of a high voltage motor.