# Single-Phase, Bidirectional, 7.7 kW Totem Pole On-Board Charging/Discharging Infrastructure
## 1 Introduction
Therefore, in [19; 20; 21; 22; 23], authors proposed a bidirectional approach to achieve the power flow in G2V and V2G modes. However, the approaches mainly focused on utilizing EV batteries in V2G mode for vehicle-to-home functions, reactive power operation, and distributed energy storage. In [2], [PERSON] et al. presented a review on the existence of various topologies, future trends, challenges, and technologies used for an on-board BDCI. Similarly, [PERSON] et al. [24] and [PERSON] et al. [25] presented a review on bidirectional power converters. Amongst various bidirectional PFC topologies, the full-bridge topology is the most common due to its simple structure and control flexibility, achieving unity PF operation easily. However, harmonic distortion of the current waveform can be a major concern, and alternate control methods need to be identified to answer this problem. Moreover, the full-bridge bidirectional converter requires bus capacitor of higher capacitance to act as an intermediate energy storage element, which increases the cost and footprint of the system and reduces its reliability and power density capability. Therefore, to improve the reliability and power density capability, and reduce the size of bus capacitor, researchers have emphasized on using wideband gap (WBG) devices [26; 27]. In [28; 29; 30], authors reported that the GaN and SiC WBG devices have better figure-of-merit, significantly better reverse recovery property, and lower switching losses as compared with the conventional Si MOSFETS. In this respect, [PERSON] et al. [31] have presented an on-board BDCI, which includes SiC-based WBG for AC-DC operation, and GaN-based WBG for DC-DC operation. However, authors  
Figure 1: A bidirectional charging infrastructure. have performed critical conduction mode (CRM) or boundary mode operation to realize zero-voltage switching. In CRM operation, it is controlled to stay at the boundary condition. In CRM, constant on-time control is used to change line voltage across the line cycle. Simultaneously, the reset time for the input inductor varies and the operating frequency changes accordingly, in order to maintain the boundary mode operation to minimize the peak input inductor current. However, the proposed strategy imposes an extra burden of power electronics switches and control complexity. Since the CCM operation is a requirement of the high-power application, its use with WBG devices (GaN and SiC) resolves the issue of reverse recovery. [PERSON] et al. [32] and [PERSON] et al. [33] introduced SiC-based power converters, which offer low output capacitance, high voltage blocking capability, extended soft-switching range, high power density capability, low reverse recovery charge, and better thermal characteristics. Similarly, [PERSON] et al. [34] introduced an SiC-MOSFET-based, bidirectional on-board EV charger. In this article, authors have used SiC MOSFET due to the high threshold voltage, and improved turn ON and OFF times as compared with GaN WBG devices. Additionally, GaN WBG devices are limited for the low-power applications. Therefore, for the high power application SiC-based WBG devices are used for the higher efficiency. However, the use of SiC WBG devices increases efficiency significantly but fails to improve the power density. Thus, to improve the power density level of the system, the switching frequency must be increased [35]. In [35; 36; 37; 38; 39; 40; 41], many researchers have proposed a high switching frequency (from kHz to MHz)-based solution with WBG devices in order to improve the power density level. On this point, [PERSON] and [PERSON] [42] have presented an analysis of increment in power density as well as the efficiency concerning the switching frequency. The authors have analysed that the switching frequency can increase at a certain range and after that, the efficiency decreases.