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This work presents research results on designing the drive and readout circuits for a newly-developed optical vibrations sensor. Tes sensor consists of organic light-emitting diodes (OLEDs) and photodetectors (OPDs) and micro-structure to realize the function of vibration sensing. Proper operations of OLEDs and OPDS needs a driver and a readout circuit, respectively. A driver circuit is designed for...
This paper developed a portable red-blue light emitting diode phototherapy system based on the embedded technology. The device took a STM32 microprocessor as its core controller, and red and blue narrow-band LED were used as the light source, which were driven by PT4115. In order to realize the linearly adjustment of light intensity, the STM32 was used for PWM which could achieve continuously adjustable...
To solve the problem of joint speed and strength of electricity controlled flexible clutch system (DMT) in the buses, the paper proposed a control method of pulse width modulation (PWM) based on the Freescale of 16-bit MC9S12XEP100 microcontroller. Designed the DMT control circuit and used the PID control of exciting current. The test results show that PWM control solved the rapid joint lead to overshoot,...
The Chopper Circuits are widely used in practical applications, but the voltage output of open-loop Buck Chopper could not meet application requirements on stability, accuracy and rapidity. Aiming at these existing problems, this paper presents a closed-loop design, which constitutes the negative feedback by adopting incremental PI regulation and PWM control, to obtain stable and accurate output....
Modern wind turbines technology has increased the penetration of wind power generation in power system network. This leads to more complex, sophisticated interconnection requirements for reliable operation of power system. Power electronics converters are employed to control power quality so that the wind farm operation do not affect power system stability. For study of these effects, modelling of...
An unequal pulse-width modulation (PWM) is proposed for the current-fed dual-active bridge (DAB) bidirectional DC-DC converter for battery charging/discharging applications when the battery voltage is wide. The difference of the effective duty cycles between the two sides is constant in spite of the battery voltage and the transferred power. With the proposed control, zero-voltage switching (ZVS)...
In this paper, different order generalized state-space averaging (GSSA) models are derived for a three-phase dual-active-bridge (3p-DAB) dc-dc converter with PWM control scheme. The small-signal model based on GSSA model is deduced and a comparison between different models and a circuit simulation is made. Subsequently, a closed-loop control strategy with an optimal limitation unit is proposed for...
The aim of this paper is to combine the Bond Graph energy-flow modeling and the VHDL-AMS signal-flow modeling language for the simulation and the prototyping of modern switch-mode power converters. The proposed approach was used to model a specific test case, consisting of a Buck converter with a mixed-signal PWM regulator. The causal structure of bond graph paradigm provides the basis for the convergence...
The paper presents a PWM control system of a sinusoidal voltage as output of a single-phase inverter with resistive load and LC low-pass filter. First the PWM control for a sinusoidal voltage and the control loop optimization via modulus criterion for step input signal are discussed, further analyzing the stationary error for a sinusoidal signal. This error can be reduced to zero by introducing a...
In order to meet future emission regulations, increase the power production and reduce the fuel consumption the modern SI engines uses the electronic actuators such as solenoid injector, idle air control actuator, valve timing actuator etc. Engine performance and emissions are mainly depending on the accurate control of both the injection timing and fuel injection quantity of the injector. In order...
In this paper a zero-voltage, zero-current high boosting converter using an auxiliary soft-switching network is presented. The high boost ratio is realized by an interleaved boost converter with charge-pump on the load side. Due to the parallel structure of the converter, the auxiliary soft-switching network is capable of providing both zero-voltage and zero-current transitions to the main switches...
In this paper we propose the structure and the functioning of a photovoltaic (PV) connected to the electric distribution and transmission network, equipped with the malfunction detection blocks. The studies that were carried focused on the injection of a power of 16 KW, produced by a PV panel field, on the electrical network of medium voltage (25 KV). In order to the reliability of the injection system...
This paper presents the key calculation equations for the diagram of a direct buck converter with zero-voltage power switch transition and PWM control, and demonstrates a converter simulated in the MATLAB environment.
This paper presents the key calculation equations for zero-voltage transition and PWM control in a direct boost converter, and demonstrates results of a converter simulation.
A zero-voltage transition network is proposed for a high-gain boost converter. The high-gain is realized by an interleaved boost converter with charge-pump on the load side. An auxiliary zero-voltage transition network; comprising a switch; an inductor and three diodes; is proposed to realize zero voltage turn-ON of the main switches. The resonating inductor of the auxiliary circuit creates resonance...
The paper is focused on power flow control in energy systems with grid-on renewable energy sources employing time-proportional controlled and phase angle controlled resistive loads (like boilers) to balance energy produced by the sources. The system operational properties are described and major mechanisms affecting power and voltage quality are identified. Contributions of the pulse-width regulated...
Lighting is closely related to our daily life; for different places, the types of the lighting designs and the energy-saving controls are very different; however, which can determine whether the lighting energy-saving control can succeed or not. The most frequently-used energy-saving methods include turning on/off lamps according to timing, turning on/off lamps by divided loops, using high-efficiency...
In this paper a comprehensive overview of multilevel matrix converter topologies is proposed nowadays as an alternative to the traditional AC/DC/AC multilevel converters. The operation principle and characteristics of the neutral-point clamped and cascaded H-bridge multilevel matrix converters are explained in detail. Simulation results of three-level NPC sparse matrix converter are presented to study...
Electromagnetic levitation system (EMLS) is inherently unstable and strongly non-linear in nature. In majority cases the closed loop system has been stabilized by classical controller utilizing linearlized model of EMLS. The linear classical controller has a restricted zone of operation. But it is essential to design a control scheme so that EMLS can operate for a large air-gap stably and at the same...
This paper proposes a power-loss reduction technique for a kW-scale isolated dc-dc converter, which installs a novel PWM control to achieve the soft-switching of primary side MOS-FETs. As a result, the efficiency is achieved over 90% in a wide load range. Moreover, the temperature of the primary side MOS-FETs can be reduced by 30 degrees when compared with the conventional method, and the power-density...
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