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Co-simulation enhances the efficient simulation development even for complex systems reducing time to market and computational effort. This work aims to develop a marine hybrid power system simulator using a co-simulation approach. The subsystems are packed as Functional mock-up units (FMUs) with the standard interface called functional mock-up interface (FMI). The FMUs for major subsystems are generated from the previously developed dynamic system model. However, FMUs developed by the partners are also compatible for the implementation. These FMUs are implemented in an open simulation platform's (OSP's) software Kopl and Co-Sim App to develop a system simulator. The use of a co-simulation framework for realtime virtual testing and various model fidelity implementation is studied. The developed simulator is used for testing the functionalities and operational capabilities of the studied system. It can simulate faster than real-time, thereby enhancing its use for real-time virtual testing applications. Implementing various fidelity FMUs enhances modularity. It also increases the flexibility in an FMU selection based on the simulation objectives, accuracy, and computational effort. © 2021 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

The electrification of a ship power-train is growing at a fast pace to improve efficiency and reduce emissions. The implementation of new technologies requires test and validation using various modeling approaches. However, many of the existing models of the ship hybrid power system are too complicated and demand high computational requirements, which make them inappropriate for the real-time applications. The real-time simulation model offers the benefits of testing different control algorithms along with hardware-in-the-loop testing. The bond graph-based dynamic modeling of a ship hybrid power system with a DC grid is presented as applicable to real-time simulation. The overall system model is established using different component models with varying fidelity, so-called mixed-modeling approach. In this approach, the components and control functions are modeled with different complexity such that it can capture the necessary system dynamics while minimizing the computational time. Results show that the modeled system is capable of simulating different operating strategies of the hybrid power system. Moreover, the mixed-modeling approach has enabled the system to simulate in nearly 2.5 times faster than the real-time. © 2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

Insulated Gate Bipolar Transistors (IGBTs) are semiconductor devices used in power modules for inverters and in many other applications. The challenge however is that these devices do not last their estimated life span of about 20 years and experience different failure mechanisms. It is of interest to study the failure mechanisms to give a better understanding of how to improve reliability of these devices as well as model and accurately predict the lifetime of IGBTs. The IGBT circuitry is encapsulated in silicone gel and the presence of this silicone gel prevents visual inspection of the type of failure mechanism that was experienced by the IGBT. When using a scanning electron microscope to examine the failed module, the sample may need to be gold plated and will be placed in a vacuum. Any silicone gel remaining on the IGBT module under investigation will vaporise and coat parts of the electron microscope thus damaging the microscope. Hence there is need to be able to remove all the silicone gel from the IGBT module before proper investigation into the mechanism that caused failure can begin. The results of these experiments show a practical approach on how to remove silicone in the laboratory from IGBT modules without causing any further corrossive damage to the modules under investigation.

This paper presents on-state collector-emitter voltage (υ ce, on )-load current (I c ) method to monitor chip temperature on power insulated gate bipolar transistor (IGBT) modules in converter operation. The measurement method is also evaluated using infrared (IR) thermography. Temperature dependencies of υ ce, on at load current is measured and temperature dependency calibration factor is formulated. This method needs a correction to compensate a deviation in the interconnection resistance from homogeneous temperature field in calibration to non-homogeneous field in loading. The correction parameter is obtained from a static calibration and the method is proposed in the paper. Ageing compensation in estimating the temperature is illustrated. The correction parameter is also analysed in finite element model and also investigated experimentally superimposing heat by conducting device for a longer time in the calibration.

Temperature estimation is of great importance for performance and reliability of IGBT power modules in converter operation as well as in active power cycling tests. It is common to be estimated through Thermo-Sensitive Electrical Parameters such as the forward voltage drop (V ce ) of the chip. This experimental work evaluates the validity and accuracy of two V ce based methods applied on high power IGBT modules during power cycling tests. The first method estimates the chip temperature when low sense current is applied and the second method when normal load current is present. Finally, a correction factor that eliminates the series resistance contribution on the V ce measured at high current, is proposed.

An on-state collector-emitter voltage (V ce ) measurement and thereby an estimation of average temperature in space for high power IGBT module is presented while power converter is in operation. The proposed measurement circuit is able to measure both high and low side IGBT and anti parallel diode voltages for a half bridge module which are also used to monitor the electrical degradation of the module. The V ce load current is proposed to estimate the variation of average temperature in space at every fundamental cycle of sinusoidal loading current. Initially, the calibration of voltage and junction temperature for load current level is presented and a trend of change in calibration factor for the IGBT is presented. Finally, the variation in temperature for sinusoidal variation of current is presented at initial stage and after an ageing of the IGBT. The measurement technique is simple and easy to implement into a gate driver for field applications.

A real time on-state collector-emitter (Vce) voltage monitoring is sensitive due to a stray inductance and a parasitic capacitance inside high power IGBT modules. An additional circuit used to monitor the on-state Vce introduces small current into the module. Though the current is low in comparison to the converter current, the effect on gate driving signals cannot be neglected during worst case switching operations. The worst case situation is occurred during turn-on and turn-off period of the switches at low on-time of the IGBT. Furthermore, during this period, when the common terminal of the measurement circuit is not in contact properly, the consequences of the error will be higher by deteriorating the gate driving signals. This type of error may occur due to the vibration or during implementation of the measurement circuit in the converter. This paper presents the influence of the error into the measurement and shows the measurement of current and voltage transients during the converter operation. The selection of the components for the measurement circuit is also discussed. The effect in gate driving signals with and without the error events are presented. Finally, a real time Vce measurement of IGBT module in the converter operation is presented.

Insulated Gate Bipolar Transistors (IGBTs) are key component in power converters. Reliability of power converters depend on wear-out process of power modules. A physical parameter such as the on-state collector-emitter voltage (Vce) shows the status of degradation of the IGBT after a certain cycles of operation. However, the Vce mainly shows the wear-out of bond wire lift-off and solder degradation. The Vce is normally used to estimate the junction temperature in the module. The measurement of Vce is sensitive to the converter power level and fluctuations in the surrounding temperature. In spite of difficulties in the measurement, the offline and online Vce measurement topologies are implemented to study the reliability of the power converters. This paper presents a review in wear-out prediction methods of IGBT power modules and freewheeling diodes based on the real time Vce measurement. The measurement quality and some practical issues of those measurement techniques are discussed. Furthermore, the paper proposes the requirements for the measurement and prognostic approach to determine wear-out status of power modules in field applications. The online Vce measurement for a selected topology is also shown in the paper.