Pyrocumulonimbus (pyroCb) wildfires cause devastation in many regions globally. Given that fire‐atmosphere coupling is associated with pyroCbs, future changes in coincident high index values of atmospheric instability and dryness (C‐Haines) and near‐surface fire weather are assessed for southeastern Australia using a regional climate projection ensemble. We show that observed pyroCb events occur predominantly on forested, rugged landscapes during extreme C‐Haines conditions, but over a wide range of surface fire weather conditions. Statistically significant increases in the number of days where both C‐Haines and near‐surface fire weather values are conducive to pyroCb development are projected across southeastern Australia, predominantly for November (spring), and less strongly for December (summer) in 2060‐2079 versus 1990‐2009, with future C‐Haines increases linked to increased 850‐hPa dewpoint depression. The increased future occurrence of conditions conducive to pyroCb development and their extension into spring have implications for mitigating these dangerous wildfires and urbanizing fire‐prone landscapes.

the requirement for high voltage gain step-up DC-DC converters is becoming increasingly important in many modern power supply applications. They are an essential power conversion stage in systems such as grid connected renewables and electric vehicles. Unfortunately, achieving a low cost, high efficiency, power dense, step up converter with high voltage gain is not a trivial task; yet they are highly desirable when aiming for a green power supply solution. For this reason, this paper presents a new non-isolated interleaved dc-dc boost converter with Zero-Voltage-Switching (ZVS). The proposed converter is designed around a coupled inductor, with an active clamping circuit arrangement to recycle the coupled inductor leakage energy and reduce the voltage stress on the semiconductor devices. The lack of isolation transformer improves the power density of the system. Likewise, the interleaved circuit allows for high efficiency over a broad range of operating conditions. The theoretical behavior of the power converter is fully described, and the performance of the circuit is validated through experimental results. Importantly, the circuit is capable of achieving >10X voltage gains without the need to apply extreme modulation signals to the pulse width modulation (PWM) circuit. Index Terms-High-step-up, interleaved boost converter, non-isolated, winding coupled inductors, zero voltage switching (ZVS) I. INTRODUCTION ANY green power supply applications call for a high efficiency, high step-up dc-dc converter in the power conversion stage. Typical examples include electric drives [1], grid connected inverters [2-4], electric vehicle drive trains [5], uninterruptible power supplies system (UPS) [6], telecommunication power systems, and high intensity discharge lamps [7]. Furthermore, high voltage step up gains are increasingly required when the system is powered by low voltage energy sources such as Li-ion batteries, solar arrays and fuel cells.Theoretically, conventional non-isolated boost and buck-boost converters are the simplest pulse width modulation (PWM) controlled topologies for voltage step-up. However, these converters typically have to operate under extreme duty ratios to achieve high voltage gains. As a consequence, significant voltage and current stresses are incurred by the converter devices and poor dynamic characteristics can result in the controlled output response. Furthermore, the output diodes often sustain short, but high amplitude, current M

Abstract-The influence of selected control strategies on the level of low-order current harmonic distortion generated by an inverter connected to a distorted grid is investigated through a combination of theoretical and experimental studies. A detailed theoretical analysis, based on the concept of harmonic impedance, establishes the suitability of inductor current feedback versus output current feedback with respect to inverter power quality. Experimental results, obtained from a purpose-built 500-W, three-level, half-bridge inverter with an --output filter, verify the efficacy of inductor current as the feedback variable, yielding an output current total harmonic distortion (THD) some 29% lower than that achieved using output current feedback. A feed-forward grid voltage disturbance rejection scheme is proposed as a means to further reduce the level of low-order current harmonic distortion. Results obtained from an inverter with inductor current feedback and optimized feed-forward disturbance rejection show a THD of just 3% at full-load, representing an improvement of some 53% on the same inverter with output current feedback and no feed-forward compensation. Significant improvements in THD were also achieved across the entire load range. It is concluded that the use of inductor current feedback and feed-forward voltage disturbance rejection represent cost-effect mechanisms for achieving improved output current quality.

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This paper introduces a novel technique for online system identification. Specific attention is given to the parameter estimation of dc-dc switched-mode power converters; however, the proposed method can be applied to many alternative applications where efficient and accurate parameter estimation is required. The proposed technique is computationally efficient, based on a dichotomous coordinate descent algorithm, and uses an infinite impulse response adaptive filter as the plant model. The system identification technique reduces the computational complexity of existing recursive least squares algorithms. Importantly, the proposed method is also able to identify the parameters quickly and accurately, thus offering an efficient hardware solution that is well suited to real-time applications. Simulation analysis and validation based on experimental data obtained from a prototype synchronous dc-dc buck converter is presented. Results clearly demonstrate that the estimated parameters of the dc-dc converter are a very close match to those of the experimental system. The approach can be directly embedded into adaptive and self-tuning digital controllers to improve the control performance of a wide range of industrial and commercial applications.Index Terms-Adaptive filter, dichotomous coordinate descent (DCD), infinite impulse response (IIR) adaptive filter, recursive least squares (RLS), switch mode dc-dc power converter, system identification.