High Frequency Power Electronic Converters Research Articles

Wide Bandwidth and Inexpensive Current Sensor for Power Electronics—An Augmented LEM Current Sensor

This paper presents the overall concept of a wideband and cost-effective current sensor. The sensor consists of a paralleled Hall-based current sensor (LEM) and a wideband current transformer (CT). A significant improvement of the band range and the moderate cost of the proposed sensor enable it to be used both to measure the instantaneous value in order to precisely plot the current and to obtain signals for a closed-loop control system of high-frequency power electronic converters. The sensor should be considered as an Augmented LEM Current Sensor (ALCS), which allows it to measure low- and high-frequency current signals. Finally, it allows for the measurement of a bipolar current up to 40 A. The overall cost of the sensor, along with the previously mentioned benefits, is an important feature of the proposed sensor. The present paper presents the analytical concept of the sensor (ALCS), a theoretical approach using simulation analysis, and the experimental results, which clearly demonstrate the wide range of the sensor in dynamic and static measurements.

A State-of-the-Art Review on Conducted Electromagnetic Interference in Non-Isolated DC to DC Converters

One of the most challenging and interesting field in power electronics is the ability to mitigate the Electromagnetic Interference (EMI). A natural source of EMI includes the atmospheric discharge/charge phenomena and extra-terrestrial radiation. Man-made source of EMI are line radiation, auto ignition, radio frequency interference and power lines. Suppression of EMI and enhancing the Electro Magnetic Compatibility (EMC) has become essential in high frequency power electronic converters. This review article is a one stop solution for new researchers and practitioners to understand about the effects of EMI and its suppression techniques in detail.

Current status of wireless power transfer technology and its enhanced capabilities with integration of soft-switched power converters

Soft-switched wireless power transfer system combines the advantages of both wireless power transfer (WPT) and soft-switching technology. In WPT systems, high-frequency power electronic converters are crucial part for coupling/decoupling to transfer power from sending end to receiving end without any physical contact. Soft-switching of power electronic converters can mitigate conduction losses and increase the efficiency. This paper comprises of the technical review and advancements in the technological developments of soft-switched wireless power transfer systems. This work identifies and validates the trends and challenges related to soft-switched wireless power transfer system in the current scenario. This study establishes that reaping the benefits of this technology will need a few more years of research and development. Characterization of various methods and results found in literature for various application are discussed in detail, which provides an in-depth summary of soft-switched wireless power transfer design aspects.

A Non-Invasive DC-10-MHz Wideband Current Sensor for Ultra-Fast Current Sensing in High-Frequency Power Electronic Converters

To enhance the performance of the converters along with improving their efficiency and miniaturization in many power electronics applications, a need for higher switching frequency is highly demanded. In high switching frequency converters, due to high common mode voltage issue, wideband, isolated, and low loss current sensor is required for the robust control design and ultra-fast protection. In this paper, we propose a non-invasive hybrid, isolated, and loss-less wideband current sensing method applicable for high-frequency power converters (dc-10 MHz). The proposed hybrid current sensing scheme combines two different isolated sensing technologies—a magnetoresistor sensor and a differential Rogowski coil sensor, which have complementary characteristics to achieve a wide sensing bandwidth. The proposed hybrid current sensor also utilizes planar magnetic field concentrators (MCON) using conductive materials to normalize the non-uniform magnetic field distributions generated by the current over a wide frequency range. We demonstrate through hardware prototypes and experiments that the proposed hybrid sensor yields to a very high sensing bandwidth of dc to 10 MHz. The performance of the proposed hybrid sensor is also evaluated in a 1-MHz dc–dc converter as well as a high-frequency H-bridge inverter module.

Magnetoresistor with Planar Magnetic Concentrator as Wideband Contactless Current Sensor for Power Electronics Applications

High-frequency power electronic converters require lossless, accurate, and isolated current measurement. High-frequency currents through a printed circuit board (PCB) trace generate nonuniform magnetic field around the trace. The nonuniform magnetic fields can be normalized by means of magnetic field concentrators (MCONs) using conductive materials. In this study, a novel technique for high-frequency contactless current sensing using magnetoresistor (MR) sensors with planar magnetic concentrators (MCON) utilizing conductive materials has been proposed. The effect of different MCONs on the performance of anisotropic MR (AMR) sensors for high-frequency contactless current detection has been investigated. The performance of the AMR sensor equipped with different MCONs is demonstrated experimentally with respect to a fast rise step current. A detailed frequency analysis is performed on the sensor response with different MCONs to determine the effect on the detection bandwidth of the current sensors.

Synchronisation mechanism and interfaces design of multi‐FPGA‐based real‐time simulator for microgrids

Real-time simulation of a microgrid involving massive high-frequency power electronic converters, various distributed generators and energy storage systems is computationally demanding. Due to the prominent computing resources and high speed communication, field programmable gate arrays (FPGAs) can be used together to realise the real-time simulation of a microgrid. For a complete multi-FPGA-based real-time simulator, interfaces are essential to communicate with each other and with different types of apparatus. The internal interfaces between FPGAs make it possible to operate in parallel, sharing the computational burden. External interfaces between an FPGA and physical devices contribute to the implementation of hardware-in-the-loop simulation. In this study, interfacing techniques including multi-FPGA system topology determination, time-step synchronisation mechanism and precise communication are proposed in detail. An analogue-to-digital and digital-to-analogue interface is designed to facilitate physical connections to external devices. A modified microgrid benchmark with photovoltaics and a battery is simulated with a time-step of 3 μs on a 4-FPGA-based real-time simulator. Simulation results are compared with PSCAD/EMTDC to validate the interface design.