A Bi-Directional Dual-Path Boost–Buck Hybrid Converter for High-V oltage Power Transmission Delivery Cable in

Abstract

Humanoid robots have great potential to replace human labors for various tasks in the near future. For a centralized energy storage system in humanoid robots, its battery pack (heart) is located in the main body while the energy is mostly consumed through its legs and hands, demanding thick wires (strong blood vessels) to deliver power to the actuators (muscles). In this work, we present a high-voltage power transmission cable system, which utilizes two bidirectional dual-path boost–buck (DP-BB) converters and reuses the parasitic cable inductor as the power inductor for a compact and e fficient power delivery. The proposed power system reduces the cable current by 50%–67% and reduces the cable weight by 50%. In addition, the proposed phase alignment scheme can reduce the cable current ripple in such high-voltage conversion case. The converter was fabricated in a 0.18- µm BCD process, occupying an area of 3 .56 × 5.55 mm2 and a volume of 3 .56 × 5.55 × 1.2 mm 3, including all the passive components. A 2-m 28 A WG power cable with a parasitic inductance of 1.99 µH and a resistance of 959 m Ω is utilized. It achieves a peak power conversion e fficiency of 96.7% at 16.5-W output power and supports a maximum power delivery capacity of 45 W.