Performance enhancement of wireless battery charger by a two-phase parallel inductive power transfer topology

Abstract

In this study, a wireless battery charger based on a two-phase parallel inductive power transfer (IPT) topology is developed. The charging power is shared by the two-phase parallel IPT circuits to improve efficiency. The power transferring distance can also be increased by adding the coils of the second phase. A hybrid resonant compensation of LCC-LCC/LCC-S is adopted to provide stable current or voltage output for charging the battery pack. The wireless closedloop controller is implemented via RF communication. The coils of two-phase IPT circuits share the same magnetic field space to avoid increasing system volume. Decoupling capacitors are added to the RXs to eliminate the cross-coupling effect. The proposed two-phase parallel IPT-based wireless battery charger and a single-phase IPT-based charger are both constructed. The rated output voltage and current are 86.4V and 6A for charging a common 72V/36Ah battery pack. Compared with the single-phase topology, the topology of a two-phase parallel can extend the air gap distance for providing the same output power. The efficiency is also increased by about 3% in CC mode and 2% in CV mode.

A Comprehensive Review on Efficiency Enhancement of Wireless Charging System for the Electric Vehicles Applications

“…The inclusion of additional coil improves the efficiency of the WPT system up to 91 %on transmitting more 300 W of power from source to battery. Moreover, which also improves misalignment tolerance by employing reconfigurable LCC compensation topology [116]. The two phase WPT system circuit topology is show in figure 19a, which utilized separate full bridge inverter for exciting the two coils and as well as used separate full bridge rectifier.…”

“…Also, optimal selection of the transmitter for stimulation based on the alignment with the receiver coil adds extra complexity to the system. [116][117][118][119][120][121][122][123][124][125][126] In summary, this survey has shown that multi-transmitter based WPT systems are highly efficient, and primary sided LCC compensation is the preferred compensation technique. However, it is crucial to be aware of the limitations of the system, such as reduced efficiency in case of misalignment and the complexity of optimal transmitter selection.…”