Performance Evaluation of Effective Multi-Structure Controllers for KY Negative Output Boost Converter

This paper focuses on the design of multi-structure controllers (MSCs) for KY negative output boost converter (KYNOBC) functioned in continuous current mode (CCM) for low-power source applications. KYNOBC is one of the topologies of DC–DC converter that performs the positive DC input supply voltage into a negative output voltage. Dynamic behavior of KYNOBC is nonlinear in nature because of its time-changing operation. The single loop control does not regulate the multi-parameters of KYNOBC during the line and load variations owing to that it produces poor transient and dynamic analyses. With the aim of controlling the multi-parameters of KYNOBC such as inductor current and output voltage, enriching the transient and dynamic analysis, the MSCs are recommended in this paper. In our study, MSCs for KYNOBC consist of two loops such as inner proportional (P) controller inductor current loop for modulating the converter current and outer fuzzy logic controller (FLC)/proportional integral (PI) controller voltage loop for regulating the output voltage. The P and PI values are determined from the mathematical modeling of KYNOBC and the fuzzy rules are framed based on its performance without modeling equations. The behaviors of the KYNOBC with MSCs are validated at various zones by making the MATLAB/Simulink simulations and prototype model. The controller parameters are realized in prototype field programmable gate array (FPGA). The responses are recorded to indicate the dexterous of the MSCs for it.

Energy and noise characteristics of a SEPIC buck-boost converter with unipolar and bipolar output

Some advantages of the SEPIC buck-boost converter makes it stand out from other configurations. It makes possible to obtain from a unipolar input voltage both unipolar and bipolar output voltage with a good symmetry between positive and negative output voltages. It also provides efficient performance as well as circuit simplicity in unipolar and bipolar topology owing to the use of a single switch which can be operated by available integrated controllers of boost converters. The article considers the topologies of a SEPIC buck-boost converter built according to the traditional scheme (with two inductors) and according to the scheme on magnetically coupled chokes. To analyze the processes and factors affecting the converter operation efficiency, a circuit simulation has been done using the Electronics Workbench. The results of the investigation of a pulsed DC converter of input voltage to unipolar or bipolar output voltage using SEPIC buck-boost topology are presented. The circuit simulation enables to specify the switching process characteristics, to estimate the ripple level of the input current and its spectral characteristics, and to develop recommendations concerning the choice of parameters of converters elements and generation of control signals. Based on the simulation results, the load, control, and noise characteristics of the converter are obtained. The level of symmetry of positive and negative output voltage is investigated for the converter on discrete and magnetically coupled chokes. The assessment of the effect of leakage inductance on converters with magnetic coupling of inductive elements is given. Examples of practical implementation of converters built according to the SEPIC topology are shown. It is found that the resistance of the choke windings, which is less than 0.5 Ohm, has practically no effect on the efficiency of the converter, retaining the factor of about 0.9 in a wide range of load currents, while the main source of conversion losses is a passive diode switch. Synchronous converter circuits of a number of manufacturers are more efficient, but require more complex controllers for active switches with elements for protection against through currents.

Uncertainty‐driven business cycles: Assessing the markup channel

Precautionary pricing and increasing markups in representative‐agent DSGE models with nominal rigidities are commonly used to generate negative output effects of uncertainty shocks. We assess whether this theoretical model channel is consistent with the data. Three things stand out. First, consistent with precautionary wage setting, we find that wage markups increase after uncertainty shocks. Second, the impulse responses of price markups are largely inconsistent with the standard model, both at the aggregate as well as the industry level. Finally, and in contrast to times‐series evidence, our theoretical model robustly predicts that uncertainty shocks have a quantitatively small impact on the economy.

Performance comparison of different control strategies for the regulation of DC-DC negative output super-lift luo-converter

In last years, dc-dc converters solve the most issues in the industrial application in the area of power electronics, especially renewable energy, military applications and affiliated engineering developments. They are used to convert the DC input that unregulated to regulated output perhaps larger or smaller than input according to the type of converters. This paper presents three primary control method used for negative output Super lift Luo DC-DC converter. These methods include a Voltage mode control (VMC), Current mode control (CMC), and Sliding mode control (SMC). The goal of this article is to study and selected an appropriate and superior control scheme for negative DC-DC converters. The simulation results show the effectiveness of Sliding mode control for enhancing the performance of the negative dc-dc converter. Also, this method can keep the output voltage constant under load conditions. simulation results obtained by the MATLAB/Simulink environment.