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To simplify the circuit design and control complexity of the magnetic coupling resonant wireless charging system, the radio energy transmission constant current and constant voltage charging is realized.

The purpose of this study is to simplify the circuit design and control complexity of the magnetic coupling resonance wireless charging system, in order to achieve constant current and constant voltage charging for wireless energy transmission. First, the principle of LCC/S-S compensation structure is analyzed, and the equivalent mathematical model is established; then, the system characteristics under constant current and constant voltage mode are analyzed, and the design method of system parameters is given; finally, a simulation and experimental system is built to verify the correctness and feasibility of the theoretical analysis.

The results show that the proposed hybrid topology can achieve a constant current output of 2 A and a constant voltage output of 30 V under variable load conditions, and effectively suppress the current distortion problem under light load conditions. The waveform distortion rate of the inverter current is reduced from 33.97% to 10.45%.

By changing the high-order impedance characteristics of the compensation structure, the distortion of the current waveform under light load is suppressed, and the overall stability and efficiency of the system are improved.

The purpose of this paper is to study the effects of voltage on microstructure and properties of micro-arc oxidation (MAO) ceramic coatings formed on AZ31B magnesium alloy under the constant current–constant voltage operation mode.

The wear and corrosion resistance of MAO coating on AZ31B magnesium alloy was studied by MAO in silicate electrolyte under constant current and constant voltage.

When the voltage is 360 V, the wear and corrosion resistance of AZ31B magnesium alloy is the best.

The wear and corrosion resistance of MAO coating on AZ31B magnesium alloy was studied by friction wear and electrochemical workstation.

The purpose of this paper is to implement a closed loop regulated bidirectional DC to DC converter for an application in the electric power system of more electric aircraft. To provide a consistent power supply to all of the electronic loads in an aircraft at the desired voltage level, good efficiency and desired transient and steady-state response, a smart and affordable DC to DC converter architecture in closed loop mode is being designed and implemented.

The aircraft electric power system (EPS) uses a bidirectional half-bridge DC to DC converter to facilitate the electric power flow from the primary power source – an AC generator installed on the aircraft engine’s shaft – to the load as well as from the secondary power source – a lithium ion battery – to the load. Rechargeable lithium ion batteries are used because they allow the primary power source to continue recharging them whenever the aircraft engine is running smoothly and because, in the event that the aircraft engine becomes overloaded during takeoff or turbulence, the charged secondary power source can step in and supply the load.

A novel nonsingular terminal sliding mode voltage controller based on exponential reaching law is used to keep the load voltage constant under any of the aforementioned circumstances, and its performance is contrasted with a tuned PI controller on the basis of their respective transient and steady-state responses. The former gives a faster and better transient and steady-state response as compared to the latter.

This research gives a novel control scheme for incorporating an auxiliary power source, i.e. rechargeable battery, in more electric aircraft EPS. The battery is so implemented that it can get regeneratively charged when primary power supply is capable of handling an additional load, i.e. the battery. The charging and discharging of the battery is carried out in closed loop mode to ensure constant battery terminal voltage, constant battery current and constant load voltage as per the requirement. A novel sliding mode controller is used to improve transient and steady-state response of the system.

A state‐of‐the‐art review of the present and future development of hot‐wire flow‐measuring devices.

The aim of this paper is to simulate, test and evaluate an induction heating process considering the converter's performance.

In case of continuous induction hardening processes, the load changes abruptly during the transition to Curie temperature, becoming significant considering the converter's behavior. In this paper, an induction heating system is simulated combining the numerical analysis of the electromagnetic‐thermal and electrical problem, focusing mainly on the converter's performance. The simulations are realized by using commercial FEM software and the voltage and the frequency are manually varied according to the converter's control. The system has also been implemented in an experimental setup and the results obtained have been compared with the simulations.

The importance of considering the converter's dynamics was observed during the simulations. The simulation results showed a correspondence with the experimental results, validating the simulation procedure and demonstrating that the converter's behavior has to be considered.

A power converter for a real industrial induction heating process where there is a sudden change in the load parameters is simulated and experimentally tested. The importance of considering the variation of frequency and voltage during the simulation of induction heating systems is demonstrated. Some considerations for induction heating modeling regarding converter's performance are given and the importance of converter's dynamics is introduced. In addition, a simple and flexible method of simulating the converter operation with commercial software is presented.

This paper aims to solve the typical thermal airflow sensor's high power consumption and integration difficulties, based on the FS5 thermal element and constant temperature measurement method, a flow sensor is developed with high measurement accuracy, low power consumption, small size, low cost and easy system integration.

A small wind tunnel was used to test and assess the sensor's measurement range, reaction time, stability, repeatability, measurement accuracy and multi-temperature calibration was performed in the temperature range of −10°C to 30°C. The effect of ambient temperature on the sensor's measurement data is investigated, and the coefficient correction method of power function was investigated to implement the sensor's software temperature compensation function.

The results show that the sensor is stable and repeatable, the output voltage has a power function relationship with the airflow rate, the flow rate measurement range is 0–18 m/s, the response time is less than 3 s, the measurement accuracy at high flow rates is within 0.4 m/s and the temperature-corrected airflow rate measurement error is less than 5%. Setting the temperature calibration interval to 2°C and 5°C has the same temperature compensation effect, reducing the sensor's calibration effort significantly.

This paper demonstrates that a thermostatic method is used to construct a thermal wind speed sensor that delivers accurate measurements in the wind speed measuring range of 0–18 m/s under test conditions. In addition, the sensor's performance is evaluated, and calibration tests for a wide range of temperatures are done. Finally, based on the power function correction method, a temperature compensation algorithm is proposed.

In an aqueous solution, salts of electrolyte separate into ions. This separation needs no external source of electrical potential, so no electrical energy is expended. When two electrodes are immersed in such a solution and connected to a D.C. potential, a potential gradient exists in the solution between them. Under its influence ions in the vicinity are discharged and there is movement of cations and anions in the bulk of the electrolyte, with the cations moving and getting discharged at the cathode and the anions likewise at the anode. This is now a well‐accepted fact which has been exploited industrially in electrolysis process, electrophoresis, metal electroplating, etc.

Power management of a wireless sensor node is important and needs to be designed efficiently without wasting excessive energy. The purpose of this paper is to report on the improvement of the power management of a wireless sensor node.

The design involves the implementation of solar recharging technology with single‐ended primary inductance converter (SEPIC) on a wireless sensor node in order to achieve the improvement in power management.

The combination of the solar recharging technology with SEPIC converter shows promising results for efficiently supplying the power to the wireless sensor node.

The design idea can be extended for many other electronic sensor applications, which can help to ensure an efficient power management of the sensor nodes.

The proposed design model demonstrates a new idea towards reduction of energy usage for wireless sensor nodes.

The purpose of this paper to ensure the rapid developments in the radio frequency wireless technology, the synthesis of frequencies for pervasive wireless applications is crucial by implementing the design of low voltage and low power Fractional-N phase locked loop (PLL) for controlling medical devices to monitor remotely patients.

The developments urge a technique reliable to phase noise in designing fractional-N PLL with a new eight transistor phase frequency detector and a good linearized charge pump (CP) for speed of operation with minimum mismatches.

In applications for portable wireless devices, by proposing a new phase-frequency detector with the removal of dead, blind zones and a modified CP to minimize the mismatch of currents.

The results are simulated in 45 nm complementary metal oxide semiconductor generic process design kit (GPDK) technology in cadence virtuoso. The phase noise of the proposed Fractiona-N phase locked loop has–93.18, –101.4 and –117 dBc/Hz at 10 kHz, 100 kHz and 1 MHz frequency offsets, respectively, and consumes 3.3 mW from a 0.45 V supply.

The purpose of this paper is to analyze and simulate the control techniques that can be used to control the on-board conductive battery chargers (OCBCs) for electric vehicles applications. This paper also provides a comparative study of these control techniques.

Battery chargers would play an important role in the development of new battery electric vehicles (BEVs). The control techniques of these OCBCs can significantly influence the BEV performance during the charging mode from the ac grid. In addition, the proper selection of control systems of the OCBCs has a great impact on the power quality of the AC grid during the charging period. Therefore, this paper presents the analysis of different control techniques that are commonly used to control the battery chargers. In addition, a comparative study of different control techniques of the OCBCs for BEVs is provided.

The results have demonstrated that it is possible to significantly improve the efficiency, power factor and total harmonic distortion by using proportional-integral control and proportional-resonant control. The digital control can be used to validate the selected control technique.

The main objective of this paper is to analyze the different control methods that can be used to control the OCBCs during charging mode from the ac grid. In addition, this paper presents a comparative analysis between these control methods. In this paper, a digital control based on TMS320F2808 DSP is used to implement the proper control method for OCBCs.