Active current ripple cancellation in parallel connected buck converter modules

Abstract

Parallel connection of converters has become a popular method of improving efficiency. This study first presents a design technique for a buck converter with two parallelly connected power modules (PMs), where one PM is designed with large current ripple for high efficiency. This study then demonstrates an active current ripple cancellation technique, where the current waveform of the second PM is shaped to be the exact opposite to that in the first PM, to reduce the current ripple as seen by the output capacitor. The factors that affect the overall efficiency in a parallel connected converter and the calculation of the parameters that determine the effectiveness of the ripple cancellation are reported. A prototype parallel converter is designed based on the proposed converter design technique and the current ripple seen by the output capacitor is successfully reduced by 66% with the proposed ripple cancellation technique, under different line and load conditions. & The Institution of Engineering and Technology 2013 Subscript m, x and i are also used with the list of symbol above to distinguish the parameters for the main PM, auxiliary PM and interleaved converter PM (e.g. δ m , δ x and δ i are the duty cycles for the main PM, auxiliary PM and interleaved PM, respectively).

Optimal peak‐efficiency control of the CMOS interleaved multi‐phase step‐down DC‐DC Converter with segmented power stage

“…OUT T CLK (10) In the process of capacitor charging, one half of the energy is dissipated on the transistor driver output resistance, and one half is stored in the capacitor. On this account, term ½ in (9) disappears.…”

“…On this account, term ½ in (9) disappears. Equalling (9) and (10) then results in the energy balance (11) This allows to obtain the value of I B , which is to be integrated by capacitor C matched to C GS(N)…”

“…Moreover, it appears that fundamental frequency of all AC components is n-time higher for the multi-phase converter, when compared with its single-phase counterpart [7][8][9]. Alternatively, further reduction of the residual AC ripple current/voltages are described in the literature, as for instance method based on active ripple cancellation [10], or interleaved converters with coupled inductors [11].…”

An Optimized Switching Strategy for a Ripple-Canceling Boost Converter

“…As a result, a boost-type architecture with a large voltage gain is required to link this voltage to an inverter [1]- [3]. Another important requirement for a converter in renewable energy applications-e.g., fuel cells-is to drain a continuous current with minimum ripple [4], [5]. Therefore, converters combining these two features are expected to find many applications within the renewable energy field.…”

Large-Signal Characterization of Power Inductors in EV Bidirectional DC–DC Converters Focused on Core Size Optimization

“…The use of variable inductances can be found in resonant converter topologies (fluorescent lamp and LED lamp drivers), in PFC circuits, MPPT techniques, in ZVS techniques, inductive power transfer (IPT) systems and also in compensation schemes for AC voltage control [14]- [21]. In addition, several papers were recently published that deal with ripple compensation or ripple cancelation techniques using lowvoltage multiple winding inductors or integrated magnetics [22]- [25]. Currently no solutions have yet been presented for higher-power level industrial applications, with such low-level complexity implementation.…”