This paper presents a deep learning assisted synthesis approach for direct end-to-end generation of RF/mm-wave passive matching network with 3D EM structures. Different from prior approaches that synthesize EM structures from target circuit component values and target topologies, our proposed approach achieves the direct synthesis of the passive network given the network topology from desired performance values as input. We showcase the proposed synthesis Neural Network (NN) model on an on-chip 1:1 transformer-based impedance matching network. By leveraging parameter sharing, the synthesis NN model successfully extracts relevant features from the input impedance and load capacitors, and predict the transformer 3D EM geometry in a 45nm SOI process that will match the standard 50Ω load to the target input impedance while absorbing the two loading capacitors. As a proof-of-concept, several example transformer geometries were synthesized, and verified in Ansys HFSS to provide the desired input impedance.

Direct-drive wave energy converter (DD-WEC) is limited by low power density caused by low direct-drive speed. A tubular hybrid field-modulated linear generator (HFMLG) is proposed to improve the performance of DD-WEC. The generator adopted a field-modulated design to increase the output voltage of the linear generator. A hybrid excited field coil can be used to adapt to different wave situations and effectively improve the output performance of this kind of generator. The operation of the proposed generator is analyzed, and the generator performance is evaluated through finite element method and compared with those of three other generators, namely, a field modulated linear generator with parallel magnetic-circuit, a secondary surface PM field modulated linear generator, and a secondary surface PM fractional-slot linear generator. Results show that the proposed generator exhibits high power density and low cogging force. The steady output power and output voltage of are marginally higher in the proposed generator than in the conventional generators.

Ocean wave energy is sustainable and renewable energy, wave energy conversion (WEC) effectively solves the disadvantage of traditional power system with fossil energy. WEC system is the power generation process that converts wave kinetic energy of undulation and swing into electric energy, and direct‐drive WEC system (D‐DWEC) converts wave energy into electric power directly by linear generator to improve the efficiency. At present, the research of WEC system has the characteristic of interdisciplinary, multi‐system integration, engineering application, and commercial operation. This paper summarizes the types, principle, and classification of WEC system, mainly focusing on the aspects of the kinds and characteristics of linear generators used in D‐DWEC system, power post‐processing, and power control methods. At the end of the paper, giving the development trend and challenges of D‐DWEC technology, the research of ocean complementary energy generation platform with offshore wind, solar and ocean wave energy is analysed. It shows that the platform has advantages owing to stable power output, efficient utilization, ocean saving‐space, and power generation cost reduction.

Transverse flux permanent magnet linear generator (TF-PMLG) is widely used in direct drive wave energy converter (DD-WEC) because of its high power density. Traditional transverse flux machine (TFM) is designed and built in form of translator-PM. But translator-PM configuration needs a large amount of PM and the cost is high in long stroke application, like DD-WEC. Recently, the stator-PM linear machines have gained more attention for reducing the PM volume and improving the generator performances under low-speed conditions. In this paper, a novel stator-PM TF-PMLG for DD-WEC has been proposed. The fundamental configuration and operation principle of the generator are illustrated. Then, the expressions of the back EMF and the electromagnetic thrust are derived by magnetic circuit analysis. Main dimension parameters, such as PM thickness, central angle of the outer stator shoe and pole pitch are determined and optimized based on finite element analysis (FEA). This topology has advantages of low PM consumption and high power density, and is a suitable candidate for long stroke applications, like DD-WEC, in which a high power per PM volume is usually needed to reduce the amount of permanent magnet and ensure high power density.

Undersea direct-drive wave energy converters (UDDWEC) have the advantages of high energy absorption and good resistance to wind and waves. This paper proposes a robust faster joint control for the hybrid energy storage system (HESS) in the application of islanded microgrid with UDDWEC. Wave power systems capture maximum power under different conditions, considering regular and irregular waves. The interconnection damping assessment-passivity based controller (IDA-PBC) used as an outer voltage controller regulates the DC link voltage to the desired value by generating reference values for the supercapacitor current and the battery current. The model predictive control (MPC) used as an inner controller tracks the reference state variables generated by the outer voltage controller. HESS is employed to mitigate the discrepancy in average and instantaneous power between the wave generation system and the DC load. The output of the wave power system is investigated under frequency and magnitude variations in wave elevation. It was verified that the system can maintain stability quickly when the load varies. The proposed control structure is verified through simulation and experimental results.

Direct-drive wave energy converter (DD-WEC) simplifies the structure and improves the efficiency of wave energy conversion. Permanent magnet transverse flux linear generator (PMTFLG) combines the merits of transverse flux linear generator (TFLG) and permanent magnet linear generator (PMLG), and is suitable for low-speed high thrust density applications, like DD-WEC. However, it suffers from a significant demerit which is the high cost due to the rare earth permanent magnets (PMs). A stator-PM spiral translator PMTFLG (ST-PMTFLG) is proposed in this article. Armature winding and PMs are arranged in outer stator and inner stator, respectively while the translator is made of spiral steel blocks and nonmagnetic blocks. Similar to the magnetically geared machine, the proposed topology is suitable to be used in low-speed long-stroke application. Results show that ST-PMTFLG has advantages of low PM consumption and high thrust density. The thrust per PM volume of 12/11 ST-PMTFLG is 4.18 MN/m ³ .