Designing a unified damping and cross-coupling rejection controller for LCL filtered PV-based islanded microgrids

This article presents a comprehensive review on the reliability assessment and charging methodologies of electric vehicles (EVs) connected to the grid. In the transportation industry, EVs are acknowledged as effective ideas for reducing the consumption of fossil fuels and the emission of greenhouse gases. The article presents a critical survey of the various types of EVs and their performance, generally depend on the proper interface between power electronics converters and energy storage devices. Bi-directional converters are utilised to enhance efficiency and prolong battery life. This article explores an in-depth analysis of the grid connected converter topologies for distribution networks, charging infrastructures and standards, battery charging technologies (merits/demerits), and most advanced off-board and on-board EV chargers. Evaluating the reliability of grid-integrated EVs system is thus an important area of research. Then, the current research approaches vehicle-to-grid (V2G) and grid-to-vehicle (G2V) are demonstrated to describe travel behaviour, reliability parameters, and battery capacity associated with reliability and to assess the stability of the distribution system by incorporating EV discharging thresholds of both distribution networks and EVs. Finally, this article illustrates the positive as well as negative impacts of grid integration, issues related to EV converters, and specific suggestions for developing EV charging stations (CS) in the future. 

https://onlinelibrary.wiley.com/doi/pdfdirect/10.1049/els2.12073

A comprehensive state‐of‐the‐art review on reliability assessment and charging methodologies of grid‐integrated electric vehicles

Power quality in terms of power factor (PF), efficiency, and total harmonic distortions (THDs) is an important consideration in power supplies designed for 5G telecom servers. This paper presents a different magnetic parts design and manufacturing techniques of power supplies, design and selection criteria of switching elements as well as the optimal design of control loops based on small-signal stability modeling and an appropriate stability criterion. The designed telecom power supply consists of the power factor correction (PFC) stage to increase the input power factor and the isolated phase-shift pulse width modulation (PWM) zero-voltage switching (ZVS) DC–DC converter stage to regulate the supply voltage to the specified load value while maintaining a high conversion efficiency. A two-stage outdoor telecom power supply with a power rating of 2 kW was designed and fabricated on a printed circuit board (PCB). The distinct two-stage power components of the power supply were subjected to loss analysis. Furthermore, PSIM simulation and experiments were used to demonstrate the total harmonic distortions (THDs), voltage ripples, power efficiency, and PF performance of the supply current for the proposed power supply under various operating situations. This work produces an industrial high power density power supply with a high PF, low THD and high conversion efficiency which is suitable for telecom power server applications.

/pdf/design-and-fabrication-of-an-isolated-two-stage-ac-dc-power-23ejnysl.pdf

Design and Fabrication of an Isolated Two-Stage AC–DC Power Supply with a 99.50% PF and ZVS for High-Power Density Industrial Applications

Renewable energy (RE) sources play an important role that not only reduces the pressure on fossil fuels but also produces safe and clean energy by developing the microgrid (MG) technology that fulfills the excess demand for power throughout the world. The technological development and the blessing of information and communication technology converts the MG technology to a smarter one, termed as smart grid (SG) and virtual power plant, by establishing a two‐way communication between the consumers and service provider with the aid of smart metering infrastructure, dynamic pricing scheme, energy management system, smart transmission and distribution system. The transformation of the traditional power system to SG enhances the efficiency, flexibility, resiliency, and robustness of the power system due to the increasing level of cyber security and automation. A directional pathway from conventional to smart power system has been carried out in this paper by addressing the present status of the power system, challenges during the operations, and possible solutions. Initially, the control operation of MG with RE and energy storage system has been investigated which is essential to understand the operation complexity and challenges due to the variable nature of the RE, load dynamics, and uncertainties. But the facilities of end‐user feedback, dynamic pricing scheme, cyber security, and smart metering system are not present in MG technology that hampers the proper regulation of controlling operation, generating and distributing energy as well as energy losses. The development of SG with smart technologies overcomes these problems by proper controlling of power usage. Finally, this paper provides a path to move the MG toward SG by analyzing the technical and critical challenges of smart devices, equipment integration, and their control issues and provides possible solutions to overcome the integration and control challenges for a reliable and sustainable operation.

Microgrid to smart grid's evolution: Technical challenges, current solutions, and future scopes

This paper presents the LC-type passive wireless sensing system for the simultaneous and independent detection of triple parameters, featuring three different capacitive sensors controlled by two mechanical switches. The sensor coil was connected with three different capacitors in parallel and two mechanical switches were in series between every two capacitors, which made the whole system have three resonant frequencies. The readout coil was magnetically coupled with the sensor coil to interrogate the sensor wirelessly. The circuit was simulated advanced design system (ADS) software, and the LC sensor system was mathematically analyzed by MATLAB. Results showed that the proposed LC sensing system could test three different capacitive sensors by detecting three different resonant frequencies. The sensitivity of sensors could be determined by the capacitance calculated from the detected resonant frequencies, and the resolution of capacitance was 0.1 PF and 0.2 PF when using the proposed sensor system in practical applications. To validate the proposed scheme, a PCB inductor and three variable capacitors were constructed with two mechanical switches to realize the desired system. Experimental results closely verified the simulation outputs.

/pdf/lc-passive-wireless-sensor-system-based-on-two-switches-for-3hx8i3ps.pdf

LC Passive Wireless Sensor System Based on Two Switches for Detection of Triple Parameters

A resonant damping control and analysis for LCL-type grid-connected inverter

More electric aircraft challenges: A study on 270 V/90 V interleaved bidirectional DC–DC converter

Nowadays, power converters with reduced cost, compact size and high efficiency are evolving to overcome the emergent challenges of renewable energy integrations. In this context, there is an increased demand for well-designed power converters in renewable energy applications to reduce energy utilization and handle a variety of loads. This paper proposes a center-tapped bridge cascaded series-resonant LC dual active bridge (DAB) converter for DC-DC conversion. The low part count of the proposed converter enables a high-power density design with reduced cost. The proposed converter offers reduced conduction losses as the reverse current is eliminated by adopting current blocking characteristics. Reverse current blocking also enables zero voltage switching (ZVS) and zero current switching (ZCS) over a wide operating range. Therefore, using a simple fixed frequency modulation (FFM) scheme offers a wide operating range compared to a conventional DAB converter. A thorough comparison of the proposed converter and a conventional DAB converter is provided based on conduction losses and switching losses to illustrate the performance improvement. Lastly, the effectiveness of the proposed converter is validated through simulation and experimental results.

/pdf/practical-evaluation-of-loss-reduction-in-isolated-series-2ag2dd2j.pdf

Practical Evaluation of Loss Reduction in Isolated Series Resonant Converter with Fixed Frequency Modulation

Resonance is one of the most significant challenges in a voltage source inverter interfaced with the grid through an LCL filter. The capacitor current (CC) damping control methodology is considered due to its high‐quality of grid injected current feature. It is widely accepted that the proportional CC feedback compensation damping method becomes ineffective at critical resonance frequency due to control loop delays and may result in an unstable system under grid impedance or filter parameters variations. A suitable differential compensator placed in the CC feedback path can address this issue with a trade‐off between robustness and noise rejection capability. This paper offers a different design method called parallel feedforward compensation (PFC) method, which builds an almost strictly real positive (ASRP) plant and realized damping with enhanced stability features. In the proposed alternative, a compensator consisting of a damping gain and a sampled delay is placed across the filter plant and filter CC feedback loop and the joint output of this augmented plant is then transmitted back at the reference point on the input side of the inverter to attenuate the undesirable resonance peak. The control response and stability performance analysis show that the suggested methodology offers a wide damping region, high robustness, and improved control performance. Simulation and experimental results are presented to confirm the theoretical findings.

Danish Khan

Papers

A resonant damping control and analysis for LCL-type grid-connected inverter

More electric aircraft challenges: A study on 270 V/90 V interleaved bidirectional DC–DC converter

Practical Evaluation of Loss Reduction in Isolated Series Resonant Converter with Fixed Frequency Modulation

LCL‐filter resonance suppression in grid‐connected inverter based on strictly real positive plant strategy

Active damping of LCL-Filtered Grid-Connected inverter based on parallel feedforward compensation strategy