Ocean surface wind speed is important for numerical prediction of the marine environment, marine disaster monitoring, sea–steam interaction, meteorological prediction, climate research, and so on. At present, ocean surface wind speed retrieval models extract DDM features from the delay-Doppler domain, the angle of which is single, where certain detail information cannot be effectively extracted from the image. To improve the accuracy of wind speed retrieval, starting from the feature extraction, this letter proposes a frequency-informed neural network (FINN)-based wind speed retrieval. First, the wind speed retrieval model based on the delay-Doppler domain and frequency domain is constructed, based on the extraction of features from the DDM delay-Doppler domain, the features from the DDM frequency domain are also extracted, so the wind speed retrieval is performed separately by extracting features from different angles. Then, a multimodel fusion scheme based on dynamic weights is designed, which can dynamically weight submodels according to different input samples, and realize the dynamic fusion of delay-Doppler-domain retrieval results and frequency-domain retrieval results. Finally, the improved gradient loss (IG Loss) function is proposed. Contrast experiments and ablation studies prove that the present algorithm has excellent retrieval performance.

To meet the urgent demand for high efficiency and high power density inductive power transfer (IPT) system in key applications such as electric vehicles, deep-sea intelligent equipment and consumer electronics, this article proposes a novel IPT system with full range soft-switching operation and magnetic integrated structure based on the dual-decoupling concept. With the help of the novel active auxiliary network, the switching tubes in the high-frequency inverter can achieve zero-voltage switching (ZVS)-ON and ZVS-OFF within the full power range. Meanwhile, the proposed magnetic integrated structure based on the dual-decoupling concept integrates the resonant inductor in the auxiliary circuit and compensation network into the transmitter coil, sharing a set of magnetic core. It can achieve the decoupling between the auxiliary resonant inductor and the compensation resonant inductor, as well as the decoupling between the two resonant inductors and the power transfer coils, with the effect of suppressing leakage flux and reducing the proximity effect of high-frequency currents. The proposed dual-decoupling concept can be extended to other high-order compensation IPT topologies with multiple resonant inductors. The above schemes can effectively reduce the system’s switching losses and the overall core losses of the system, improve the transfer efficiency of the system across the entire power range, and possess many advantages such as high power density, efficiency, and magnetic flux balance. Eventually, the advantages of the proposed scheme are validated through the construction of a 1kW experimental prototype.

Aiming at the topology of high-frequency link dual matrix inverter (HFLDMI), an intermediate hexagonal modulation strategy based on topology decoupling and vector decoupling is proposed, which effectively suppresses the common mode voltage (CMV) of the system and realizes soft switching of switches. Firstly, the working mode of HFLDMI under the proposed modulation strategy is analyzed in detail. After that, the accurate switching models of CMV and zero sequence voltage (ZSV) of HFLDMI are established and the CMV and ZSV of HFLDMI are compared with the CMV and ZSV of a conventional dual inverter. Finally, the correctness of the proposed modulation strategy is verified by simulation software. The results show that the CMV amplitude of HFLDMI is suppressed below V dc /6 and the ZSV is zero.

To meet the charging requirements of constant current output (CCO) and constant voltage output (CVO), and maintain constant output when the couplers are misaligned in inductive power transfer (IPT) system, a hybrid three-coil IPT topology with high misalignment tolerance is presented. Two mode conversion switches, one inductor and two capacitors are added on the receiver side of the conventional series series (SS) topology to realize the switching SS and S/LCC topologies, so as to achieve the CCO and CVO. The system combines all the advantages of the two topologies, does not need to switch frequency, and has simple control. Moreover, it gets rid of the wireless communication between the receiver and the transmitter. The transmitter adopts two coils connected in reverse series to improve system’s misalignment tolerance. The operating principle of the topology is introduced in detail, and the main idea of parameter design is also given. Ultimately, a 100W experimental prototype is built to verify the effectiveness and superiority of the proposed hybrid IPT topology.

Due to the skin effect, parameters of motor windings change over frequency. In order to solve the problem in traditional Kalman-filter based deadzone compensator that the performance is sensitive to parameter mismatch, a novel deadzone compensation scheme with high robustness is proposed. Firstly, a deadzone compensation scheme based on Kalman filter technology is presented, and motor parameter variation over frequency changes is studied. Secondly, the impact of motor parameter mismatch is analyzed, and the verification of the performance deterioration is done via computer simulation. Thirdly, an Adaline neural-network(NN) based robustness enhancement algorithm is proposed to analyze the current error components. The performance deterioration is compensated by using the analyzed results of the robustness enhancement algorithm. Finally, the robustness against parameter sensitivity of the proposed method under various parameter mismatch conditions is fully studied and verified.

This paper presents the development and implementation of a wavelet modulation (WM) technique for the three-phase three-level voltage source inverter. The WM technique is based on constructing a nondyadic-type multiresolution analysis (MRA), which supports sampling continuous time sinusoidal signals in a nonuniform recurrent manner, then reconstructing it using inverter switching actions. The simulated and experimental performances of the three-phase three-level inverter, which is realized by the WM technique, are investigated. To compare the performances of WM technique, those of PWM and SVPWM techniques are obtained. The results show that the high magnitude of fundamental components and significantly reduced harmonic contents of the inverter outputs can be achieved by using WM in the three-phase three-level inverters and it can be easily realized.

This paper introduces a cascaded high step-up converter realized with a tightly coupled three-winding coupled inductor. Compared with existing high step-up converters, the proposed converter features that the smaller the turns ratio, the larger the conversion gain. So, the name coupled inductor-reverse is given to represent reverse-coupled inductor principle of operation. In addition, diode-capacitor circuit is introduced to not only recycle leakage energy to output, but also further lift voltage conversion gain. This paper illustrates operation principle of the proposed converter, discusses effect of leakage inductance on voltage gain, and deduces voltage and current stresses of components. Finally, a prototype rated at 400 W has been established, and experimental results verify correctness of the above theoretical analysis.