A Variable Phase-Shift Control Scheme for Extended-Duty-Ratio Boost Converter With Automatic Current Sharing in High Step-up High Current Application

Abstract

Recently, an extended-duty-ratio (EDR) boost converter has attracted great attention of many scholars. However, the EDR boost converter with fix phase shifts is difficult to achieve phase-to-phase current sharing over a wide range of duty ratio. In this paper, a variable phase-shift control strategy is proposed to further expand its current sharing range for the EDR boost converter. Under the proposed control strategy, the EDR boost converter can operate in wide range of duty ratio varying from 0.5 to 1 with automatic current sharing between phases since two adjacent phase shifts can be adjusted to guarantee that the energy stored in certain inductor is only transferred to the next phase capacitor step by step for generating high step-up output voltage. Next, the steady-state analysis of the EDR boost converter under the proposed control strategy is discussed thoroughly, and the switch voltage stresses and current stresses are also analyzed. Finally, a 300 W, 3.3 V to 38.9 V, four-phase EDR boost hardware prototype has been built. The effectiveness of the proposed control strategy is verified by the experimental results of the built prototype.

A Four-Phase Interleaved Buck-Boost Converter With Changed Load Connection for the Fuel Cell Activation

“…Generally, the value of the capacitor is large, and is approximately equivalent to a constant voltage source. According to the relationship between the charge amount Q and the capacitance C o in one switching period, the output capacitor voltage ripple V Co can be expressed as the equation (20). Combined with equation ( 18), the high side voltage ripple of the proposed CLC-FIBC under different duty cycles can be calculated as…”

“…The voltage gain versus the duty cycle of the CLC-FIBC is shown in Figure 5. Table 1 gives some comparisons between the proposed CLC-FIBC and interleaved DC-DC converters in other papers as [16], [20], [29]. The voltage and current tress of [20] has a complex expression, and therefore is not listed in Table 1.…”

“…Table 1 gives some comparisons between the proposed CLC-FIBC and interleaved DC-DC converters in other papers as [16], [20], [29]. The voltage and current tress of [20] has a complex expression, and therefore is not listed in Table 1. The voltage and current tress of [20] is larger than the CLC-FIBC.…”

“…V. Samavatian et al proposed the input/output magnetically coupled interleaved buck-boost converter for the FC power conditioner to obtain a high efficiency and nonplusing I/O currents [19]. Combining multiphase interleaved technology and the high step-up technology, the high step-up interleaved DC-DC converters could be obtained [20]- [25]. H. Xiao et.al proposed a fix phase shifts extended-duty-ratio boost converter with a variable phase-shift control strategy to expand current sharing range [20].…”

“…Combining multiphase interleaved technology and the high step-up technology, the high step-up interleaved DC-DC converters could be obtained [20]- [25]. H. Xiao et.al proposed a fix phase shifts extended-duty-ratio boost converter with a variable phase-shift control strategy to expand current sharing range [20]. L. Zhang proposed an alternating phase shift control strategy for the interleaved boost converter with the voltage multiplier for the FC power conditioner [24].…”