Proposed Operation Mode Research Articles

Control Strategy of Flyback Microinverter With Hybrid Mode for PV AC Modules

This paper presents a control strategy of a flyback microinverter with hybrid operation mode for photovoltaic ac modules. The proposed control strategy consists of two components: the proportional-resonant (PR) controller with the harmonic compensator (HC) and the hybrid nominal duty ratio. Compared to the conventional control strategy using the proportional-integral controller, the PR controller with HC provides a higher system gain at the fundamental and harmonic frequencies of the grid without using a high proportional gain in both operation modes. Then, it enhances the tracking speed and disturbance rejection performances satisfying the desired stability. Moreover, by applying the hybrid nominal duty ratio yielded from the proposed operation mode selection, the disturbance rejection is achieved more effectively, and the control burden is reduced. Finally, the simulation and experimental results were shown to verify the tracking speed and disturbance rejection performances of the proposed control strategy.

Intermittent feeding batch distillation with liquid exchange between two columns for separation of binary mixtures

Batch distillation column with top vessel and bottom vessel is a new and promising structure. In the basis of it, a new operation strategy that two columns operate in parallel with liquid exchange under total reflux is proposed to separate binary mixtures in this article. A mathematical model is setup for the simulation. Operation time and yield of different feeding concentration and holdup in vessels are compared and discussed. The results show that there is an optimal holdup for different feeding concentration and the total yield increases with the growth of total charge. Furthermore, the proposed operation mode is verified experimentally and it reveals significant potential for separation with higher efficiency and lower pressure drop.

On-Chip FPN Calibration for a Linear-Logarithmic APS Using Two-Step Charge Transfer

This paper proposes a novel fixed pattern noise (FPN) calibration technique for a linear-logarithmic active pixel sensor (APS) based on the conventional four-transistor pixel structure. The offset FPN originated from the threshold characteristic variation of the transfer gate is calibrated with the proposed two-step charge transfer method, without any modification of the pixel structure or image-processing steps. The prototype sensor is fabricated by using a 0.13-μm CMOS image sensor process. The chip includes a 320 × 240 pixel array with a 2.25 μm pixel pitch and the peripheral circuitry. A wide dynamic range of more than 105 dB has been achieved from the proposed operation mode while maintaining the offset FPN less than 0.58% over the entire dynamic range.

Memoryless Wide-Dynamic-Range CMOS Image Sensor Using Nonfully Depleted PPD-Storage Dual Capture

A new low-cost high-performance dual-capture image sensor for wide-dynamic-range (WDR) applications is proposed. The proposed pixel uses a pinned photodiode (PPD) as a charge storage to achieve a WDR operation capability. By controlling the applied voltage at a transfer gate (TG) of the pixel to operate the PPD in a nonfull-depletion operation mode, the fixed pattern noise (FPN) that originated from the threshold characteristic variation of the TG is efficiently calibrated without additional circuitry or image processing steps. The prototype sensor was fabricated by using a 0.13-μm CMOS image sensor process. The chip includes a 320 × 240 pixel array with a 2.25-μm pixel pitch. A WDR of 91 dB has been achieved from the proposed operation mode while maintaining an FPN less than 0.7% over the entire dynamic range.

Design and Verification of proposed Operation Modes of LLC Converter

The subject is a comprehensive research on issues of power electronic converters operating at very high switching frequency. This is a group of inverters applicable particularly in the power supply, respectively automotive products. The main purpose of the use of high switching frequency is a high value of power density and reduced weight and dimension parameters of the device.DOI: http://dx.doi.org/10.5755/j01.eee.18.8.2606

Operationally enhanced folded hypercubes

Recently, several variations of the hypercube have been proposed to enhance its performance and reliability. The folded hypercube is one of these variations, in which an extra link is added to each node providing a direct connection to the node located farthest from it. In this paper, we propose a new operation mode of the folded hypercube to enhance its performance and fault-tolerance. There are (/sub ksup n+1/) regular k-cubes within a folded hypercube of dimension n, denoted by FQ/sub n/. We introduce another type of hypercube, called the twisted hypercube, to improve the performance and fault tolerance of the folded hypercube. The problems of finding a subcube of given size in an FQ/sub n/ and routing messages within the subcube are addressed for the proposed operation mode. The advantages of the proposed operation mode over the regular-hypercube operation mode are analyzed in terms of dependability and robustness. The proposed operation mode is shown to make significant improvements over the regular-hypercube operation mode in both dependability and robustness. Because the new operation mode can be applied to only an (n-1)-subcube level for a given FQ/sub n/, we present general form of folded hypercube, thus enhancing the availability of subcubes of any dimension m >