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Five-level rectifiers have received widespread attention because of their excellent performance in high-voltage and high-power applications. Taking a five-level rectifier with only four-IGBT for this study, a sliding mode predictive control (SMPC) algorithm is proposed to solve the problem of poor dynamic performance and poor anti-disturbance ability under the traditional model predictive control with the PI outer loop.

First, mathematical models under the two-phase stationary coordinate system and two-phase synchronous rotating coordinate system are established. Then, the design of the outer-loop sliding mode controller is completed by establishing the sliding mode surface and design approach rate. The design of the inner-loop model predictive controller was completed by discretizing the mathematical model equations. The modulation part uses a space vector modulation technique to generate the PWM wave.

The sliding mode predictive control strategy is compared with the control strategy with a PI outer loop and a model predictive inner loop. The proposed control strategy has a faster dynamic response and stronger anti-interference ability.

For the five-level rectifier, the advantages of fast dynamic influence and parameter insensitivity of sliding mode control are used in the voltage outer loop to replace the traditional PI control, and which is integrated with the model predictive control used in the current inner loop to form a novel control strategy with a faster dynamic response and stronger immunity to disturbances. This novel strategy is called sliding mode predictive control (SMC).

This paper aims to propose a low-power complementary MOS (CMOS) current sensor for control circuit in an integrated DC-DC buck converter.

The integrated DC-DC converter, which is composed of feedback control circuit and power block, is designed with 0.35-µm CMOS process. Current sensor in the control circuit is integrated with sense-FET and voltage-follower circuits to reduce power consumption and improve its sensing accuracy. In the current-sensing circuit, the size ratio of the power metal oxide semiconductor field effect transistor (MOSFET) to the sensing transistor (K) is 1,000, and a current-mirror is used for a voltage follower. N-channel MOS acts as a switching device in the current-sensing circuit, where the sensing FET is in parallel with the power MOSFET. The amplifier and comparator are designed to obtain a high gain and a fast transient time.

Experiment shows that the current sensor is operated with accuracy of more than 85 per cent, and the transient time of the error amplifier is controlled within 100 µs. The sensing current is in the range of a few hundred µA at a frequency of 0.6-2 MHz and an input voltage of 3-5 V. The output voltage is obtained as expected with the ripple ratio within 5 per cent.

The proposed current sensor in DC-DC converter provides an accurately sensed inductor current with a significant reduction in power consumption in the range of 0.2 mW. High-accuracy regulation is obtained using the proposed current sensor. As the sensor utilizes simple switch-type voltage follower and sense-FET, it can be widely applied to other low-power applications such as high-frequency oscillator and over-current protection circuit.

The purpose of the paper is to develop high accurate and unified maximum power point tracking technique that tracks the maximum power from both the photovoltaic (PV) array and wind energy conversion system, (an unified maximum power point tracking technique implemented for both wind and solar sources to track maximum power with higher accuracy).

In recent times, multi-input Direct Current- Direct Current (DC-DC) converter has attracted attentiveness, to conserve more energy and to achieve more efficiency. The kinetic energy of the vehicle is converted to electrical energy and further stored into the battery, during the regenerative braking (moreover, the battery gets charged during the regenerative braking process by converting the kinetic energy of the vehicle into electrical energy). During such a process, only the pulse width modulation schemes of the inverter are changed. To charge electric vehicles (EVs), two renewable resources as solar and wind are combined to produce electric power. Therefore, it was conveyed that the EV will be continuously getting power without interruption using various sources and regenerated power.

The performance and effectiveness of the proposed system are studied by extensive simulations and (are) validated using a prototype of the system. The results prove that the proposed system achieves an efficiency of 95.2%, which is higher than that of the multi-input DC-DC converters existing in the literature.

A novel multi-input DC-DC landsman converter for powering plug-in hybrid electric vehicles (HEVs) is proposed in the research. This method proposes a new cost effective and efficient technique for HEVs with brushless DC motors. Wind power, battery and PV panel are used as the input sources for the proposed converter.

Should allowance for fatigue be made in Rating? The orthodox answer to this is that it should not.

The purpose of this paper is to design the control for a new type of DC converter that can be used in low voltage and low power DC drives, e.g. in cars and robots.

Based on the theory of the switching systems, the existence condition of the limit cycle for the novel DC/DC converter is formulated.

The feed forward control which realizes the limit cycle is designed. The first experimental results show that the designed control of the DC/DC converter is effective in solving the control problem of DC drives and allows the use of a low input voltage as power source for the standard DC drive.

Today DC/DC converters play a key role in power conversion and distribution. The presented DC/DC converter has a very simple circuit and allows changing the output voltage in the wide range that is needed for the DC drive control.

Smiths Industries is to supply the head‐up display system for the Sea Harrier. The company will design, develop and make the electronic head‐up display and weapon aiming computer system for the latest version of the HS Harrier which will operate from Royal Navy ships.

THE Trident has been designed from the outset for the eventual introduction of completely automatic landing.

An automated fully stressed design approach based on the Xie and Steven algorithm is presented. With this algorithm a fully stressed design is obtained by a gradual removal of low stressed material. By applying this evolutionary procedure a layout or topology of a structure can be found from an initial block of material. A fully integrated, interactive program is presented which incorporates automatic mesh generation, finite element analysis and the fully stressed design algorithm. The feasibility of the approach is demonstrated using several examples.

The purpose of this paper is to differentiate human responses to different light switch designs to determine the effects of these common interfaces on user perceptions and use of electric lighting in public buildings.

Empirical studies were conducted to assess and examine user perceptions with regard to design characteristics of light switches, and occupants’ use of electric lighting was examined through field observations made in a public toilet.

The results point to the possibility of identifying characteristics of light switches that attract user attention and thereby encourage energy-saving behaviour in public buildings. A light switch perceived as simple but oversized affected occupants to turn off the lights more frequently when leaving the space under study as compared to switches of normal size.

Information on user perceptions of light switches may be limited by the assessments being carried out only in controlled environments. Assessing user perceptions in field observations is thus desirable, as it will provide more information on the perceptions in actual settings.

Effective design of user interfaces could provide a means of lowering energy use from electric lighting by affecting the behaviour of users. Using user perceptions to define critical design characteristics could contribute to design improvements in the interfaces with respect to users’ viewpoints.

This paper contributes to the subject with a basic, field-based approach to formulating an understanding of how design via user perceptions may encourage energy-saving behaviour.

The paper aims to deal with the exact computation of the Jacobian of a time criteria from a numerical simulation of power electronics structures, for the sizing by gradient-based optimization algorithm.

Runge Kutta 44 is used to solve the state equations. The generic approach combines numerical and symbolic approaches. The modelling of the static converter is based on ideal switches.

The paper extends the state equations to derivate any state variable according a sizing parameter. The integral expressions used for some sizing performances (e.g. average or RMS values) mix symbolic and numerical approaches. Choices are made for the derivatives of the extrema of which the search is not a continuous process. The use of an object-oriented implementation allows to have generic formulation of some design performances.

The paper aims to propose and to test formulations of sizing criteria and their gradients; so, the modelling of the study case is carried out manually. Due to generic modelling approach used for the power electronics, the model is not completely continuous. So, the derivatives according some parameters (e.g. switch controls) must be carried out by finite differences. However, as the global behaviour is continuous, it is not critical.

The proposed formulations can be easily applied on simple static converter applications. For applications with large state equations, it should be possible to use the basic model of switches used in simulation tools of power electronics. The solving process and the sizing criteria formulation (with their derivatives) are generic and can be instantiate for any study.

The approach proposes formulations giving a numerical sizing dynamic model with a Jacobian computed, if possible, by an exact derivation useful for optimization studies. The approach gives fast simulation and fast computation of the derivatives by combining numerical and analytical approaches.