A trans-inverse coupled-inductor semi-SEPIC DC/DC converter with full control range

© 1986-2012 IEEE. This letter proposes a single switch magnetically coupled dc-dc converter with a high voltage gain. The unique features of the converter are summarized as follows: 1) voltage gain of the converters is raised by lowering its magnetic turn ratio; 2) wide control range (0< D< 1); 3) continuous current from the source that makes it a suitable candidate for renewable energy applications; and 4) there is no dc current saturation in the core due to the presence of capacitor in the primary winding of the inductor. The feasibility of the proposed converter is studied in details supported by circuit analysis and simulation results. Furthermore, the proposed converter is analyzed and compared with other converters with similar features. Finally the superior performance of the circuit is validated experimentally

A New Soft-Switched High Step-Up Trans-Inverse DC/DC Converter Based on Built-In Transformer

This article proposes a new Zero-Voltage Switching (ZVS) high step-up DC/DC converter based on a built-in transformer for renewable energy applications. The proposed topology utilizes a Three-Winding Built-In Transformer (TWBT) to increase the voltage gain, but unlike most coupled-inductor-based DC-DC converters, high output voltages can be obtained under a lower magnetic turns ratio. In this circuit, with the help of a regenerative active clamp circuit, the energy of the leakage inductor from the TWBT is absorbed and transferred to the output, therefore, the ZVS conditions at turn-on time are achieved for switches. The voltage stresses across the switches of the proposed topology are limited, and the diodes reverse-recovery issue are eliminated. Due to the low input current ripple, the suggested topology can be used for renewable energy sources. Furthermore, because of the low number of components along with the soft-switching operation, the proposed circuit can offer enough high efficiency. The operational principle, steady-state analysis, and characteristics of the proposed converter are provided. Finally, a 200 W prototype with 25 V input and 400 V output voltage is built to validate the analytical results

An Accurate Battery Charger SEPIC-Coupled Inductor Using Fuzzy Type 2

Recently, the needs of electrical energy have increased in line with the increasing population in Indonesia. Electrical in order to save the use of fossil energy, renewable is used, namely solar energy. Solar energy depends on the conditions of sunlight and the temperature of the solar panel. So, if the solar panel is directly connected to the battery, it will cause the battery be damaged. To overcome this, a controlled DC-DC converter is needed to stabilize the solar panel output before connecting to the battery. The DC-DC converter that used is a SEPIC coupled inductor converter, this converter has the ability to increase efficiency, the output polarity is not reversed, and avoid input current ripple. The control used to adjust the output of the SEPIC converter is a type 2 fuzzy logic controller because it has ability to find a set point value faster than other control logics and can handle uncertainty better than a type 1 fuzzy logic controller. The output of the SEPIC converter is used for charging lithium ion battery with a capacity 12V 21Ah. The output value of the SEPIC converter is 12.6V for charging voltage and 7A for charging current. The method used for battery charging is the constant current constant voltage method (cc-cv)

Design of Zero-Ripple-Current Coupled Inductors with PWM signals in Continuous Conduction Mode

Coupled inductors are widely used in multiple outputs and interleaved dc-dc converters. Also filters often use coupled inductors as their inductive part. A generalized design procedure is proposed in this article focused on current ripple minimization and applicable to coupled inductors exposed to pulsewidth modulation signals and in continuous conduction mode. The design provides a very large inductance for all windings but one. Compared to other designs, it adapts to the existing magnetic properties of the magnetic device changing only the inductance ratio, simplifying the design and manufacturing process. It is based on the equivalent inductance value and its divergences. The only assumption applied is that the coupling coefficient among all windings is the same, which is an acceptable approximation in many magnetic core architectures. The theoretical results are experimentally verified. Not only almost zero ripple current is achieved, but also mass and volume is reduced compared to noncoupled inductors. This is an additional advantage of coupled inductors in mass and volume critical applications such as aerospace

Simulation Model of Single-Phase AC-AC Converter by Using MATLAB

The current research sheds light on the electronic power devices that work as transformers and are named according to the function. A model of a single-phase transformer AC-AC type with half-wave and full-wave quality has been proposed. Its output is controlled by power, voltage and current, which is considered an input to the load. The fixed input transformer has a variable output according to the required power, voltage and current. Inverters of this type have so many uses that they are used in many different applications, including industrial, induction motor speed control, military, medical and household, including low-light circuits, among others. A simulation involving different types of single-phase AC transformers is proposed. The models were built in two ways, the first using a diode as an electronic switch, and the second using a thyristor. Different values for the load were chosen by adopting three values of 30 ohms, 40 ohms, and 50 ohms. An alternating power supply with an RMS value of 222 volts. Simulation was carried out after modeling to test the performance of the proposed transformer and its various modes of operation. Simulation models confirmed and reinforced the working theories of the proposed structures. From the results, we can reach the possibility of changing the voltage and power values using the electronic transformer by using the frequency of closing and opening the electronic keys within specific periods according to the proposed model, which can be represented or modified

A Low Power Application-Specific Integrated Circuit (ASIC) Implementation of Wavelet Transform/Inverse Transform

A unique ASIC was designed implementing the Haar Wavelet transform for image compression/decompression. ASIC operations include performing the Haar wavelet transform on a 512 by 512 square pixel image, preparing the image for transmission by quantizing and thresholding the transformed data, and performing the inverse Haar wavelet transform, returning the original image with only minor degradation. The ASIC is based on an existing four-chip FPGA implementation. Implementing the design using a dedicated ASIC enhances the speed, decreases chip count to a single die, and uses significantly less power compared to the FPGA implementation. A reduction of RAM accesses was realized and a tradeoff between states and duplication of components for parallel operation were key to the performance gains. Almost half of the external RAM accesses were removed from the FPGA design by incorporating an internal register file. This reduction reduced the number of states needed to process an image increasing the image frame rate by 13% and decreased I/O traffic on the bus by 47%. Adding control lines to the ALU components, thus eliminating unnecessary switching of combination logic blocks, further reduced power requirements. The 22 mm2 ASIC consumes an estimated 430 mW of power when operating at the maximum frequency of 17 MHz

High Gain Magnetically Coupled Single Switch Quadratic Modified SEPIC DC-DC Converter

This article proposes, analyzes, and tests an improved high voltage gain dc-dc converter based on a single-ended primary-inductor converter (SEPIC). The proposed magnetically coupled quadratic modified SEPIC converter (MCQ-MSC) employs a coupled transformer with an optimized design to obtain a high voltage boost factor by controlling the transformer's turn ratio along with the switching duty cycle. Thanks to the unique structure of the coupled transformer, high voltage gain is obtained at low turns ratio, which is highly desirable for high voltage applications and the compact size of the converter. In addition to the coupled transformer, a voltage-boosting module is utilized to achieve a very high output voltage for a low switching duty cycle. The proposed inverter has a single switch with a wide control range of duty cycle (0<D<1), causing low conducting losses and high efficiency. Furthermore, a clamping circuit is successfully designed to remove the leakage inductance effects of the coupled transformer on the power switch. The proposed MCQ-MSC drains a continuous current from the input dc source, which makes it a suitable choice for renewable energy sources (RES). The hardware prototype of the proposed converter is tested to verify the mathematical expressions and theoretical results.acceptedVersionPeer reviewe