A novel low‐loss control strategy for bidirectional DC–DC converter

Summary Renewable sources of low voltage are an important resource in power generation systems. Many provide high output current at low voltage, as the photovoltaic modules and fuel cells systems, therefore, become more popular considering the safety requirements. In this paper, a novel current‐fed three‐phase dc‐dc converter with high‐frequency isolation transformer is proposed. This one has the main features as high dc voltage gain, reduced switches count, minimize the volume of the output/input filters, the frequency ripple of the input current and output voltage are three times higher than the switching frequency, best losses distribution and reduced stresses in the circuit. Moreover, it operates with wide‐range duty cycle, the soft‐start can be used, which allows the input current and the output voltage to be started gradually. Operating with a duty cycle of 1/3 and 2/3, the input current ripple is canceled. The proposed converter is studied qualitatively and quantitatively, being presented the operation principle in continuous and discontinuous conduction mode, dc voltage gain in each operation mode, and the voltage and current stresses for the power components sizing. To validate the operation of the proposed converter, the laboratory design example and experimental results are presented to demonstrate the performance and validate the claims of the converter for wide load variation. Experimental results are presented for a 4‐kW prototype, operating in R2 region for continuous conduction mode. Additionally, experimental results in R1 and R3 regions are obtained.

Section: Figurementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Three‐phase step‐up/step‐down isolated dc‐dc converter with wide‐range duty cycle for low dc renewable energy sources applications

Mayer

Kattel

Oliveira

2018

“…Nevertheless, the dynamic performance of the PWM rectifier based on the PI-MPC is affected by the working operations such as the variation of DC-link voltage or load. [21][22][23][24][25] In comparison to the PI control, sliding-mode control (SMC) shows stronger robustness and more excellent dynamic response to the variation of the working operations. 26 Some SMC-MPC strategies have been presented.…”

Section: Introductionmentioning

confidence: 99%

“…Generally, a PI controller is utilized to control the DC‐link voltage, and its output is performed as the active current reference which will be input into the MPC. Nevertheless, the dynamic performance of the PWM rectifier based on the PI‐MPC is affected by the working operations such as the variation of DC‐link voltage or load 21–25 . In comparison to the PI control, sliding‐mode control (SMC) shows stronger robustness and more excellent dynamic response to the variation of the working operations 26 .…”

Section: Introductionmentioning

confidence: 99%

A modified sliding‐mode controller‐based mode predictive control strategy for three‐phase rectifier

Wang

Shi

et al. 2020

Summary In three‐phase pulse width modulation rectifiers, proportional integral (PI) has been used in voltage outer‐loop to obtain the active current reference when using the conventional model predictive control strategy. However, the performance of the dynamic response is poor as large step and longer settling time are required on the active power under the load variation. To cope with this problem, a sliding‐mode controller can be employed to replace the PI controller. Nevertheless, the sliding‐mode variable structure control is discontinuous which leads to the chattering problem. In this work, a novel control strategy which combines a simplified model predictive control and a modified sliding‐mode control is proposed and investigated. The proposed strategy is supposed to reduce the effect of unexpected disturbances such as the DC‐link voltage step and the load variation. Simulation and experiments have been conducted for validation. The results indicate that the proposed strategy is feasible and has excellent dynamic response. Furthermore, it is easy to design and implement.

“…Switched‐capacitor (SC) converters are another group of DC‐DC converters that are widely used and highly interest researchers in numerous applications because of their effectiveness and capabilities . So far, many kinds of SC converters have been introduced and investigated for various applications .…”

Section: Introductionmentioning

confidence: 99%

A Zeta‐based switched‐capacitor DC‐DC converter topology

Vosoughi

Abbasi

et al. 2019

Summary This article proposes a new Zeta‐based switched‐capacitor (SC) dc‐dc converter, which has many advantages such as increased voltage gain, decreased duty‐cycle, lower voltage stress on components such as its capacitors and input switch, and increased output power over traditional dc‐dc converter structures. In traditional converters such as Zeta converter, there is only one coupling capacitor, which works as a medium for transferring the power between input and the output. However, in the proposed Zeta‐based converter, there are multiple coupling capacitors, which are used based on dc‐dc SC converter principles. By using these switched coupling capacitors, the mentioned advantages are obtained for the proposed structure, which in turn make this converter more applicable for industrial applications. The analysis has been validated by comprehensive and precise comparisons and experimental results.