Zero Voltage Switching Criteria of Triple Active Bridge Converter

Abstract

Triple active bridge (TAB) as an isolated multi-port converter is a promising integrated energy system for smart grids or electric vehicles. This paper aims to derive and analyse zero voltage switching (ZVS) regions of TAB, in which both switching losses are reduced, and EMI issues are mitigated. In the proposed closed-form solution of ZVS criteria, parameters such as the parasitic capacitance of the switches, the leakage inductance of the transformer, the switching frequency, the port voltage, the phase-shift inside and between the full-bridges are all taken into account. The analysis shows how the five degrees of freedom can be used to maintain ZVS operation in various operating points. The analysis and derived closed-form ZVS criteria are experimentally verified using a laboratory prototype. The derived analytical ZVS criteria are a powerful tool to study and optimise the operation of TAB converters.

Multidimensional Ripple Correlation Technique for Optimal Operation of Triple-Active-Bridge Converters

“…Moreover, fundamental analysis misses most of the insight into the shape of the switching patterns, which gives important information for switching loss reduction. A zerovoltage switching criterion for TAB has been introduced in [11], utilizing penta phase-shift modulation, and taking into account all the parameters of the TAB converter, including the parasitic capacitance of the switches, the leakage inductance of the transformer, and the switching frequency. However, this approach introduced in [11] neglects conduction loss.…”

“…A zerovoltage switching criterion for TAB has been introduced in [11], utilizing penta phase-shift modulation, and taking into account all the parameters of the TAB converter, including the parasitic capacitance of the switches, the leakage inductance of the transformer, and the switching frequency. However, this approach introduced in [11] neglects conduction loss. In [12], a universal analytical model of the TAB converter is developed utilizing frequency domain analysis (FDA) and then exploited to pursue total loss reduction via particle swarm optimization (PSO).…”

“…The PSO searches for minimum rms current while fulfilling ZVS constraints. As in [10] and [11], [12] employs a look-up table (LUT) to store the optimum modulation parameters preliminary calculated off-line. In [13], a generalized harmonic approximation (GHA) model is developed for the TAB converter, which is then used in an online gradient-descent optimization aiming at minimizing the derived analytical model (AM) of the total rms current.…”

Estrategia de modulación para minimizar la potencia reactiva en el enlace de CA de convertidores CC-CC de tres puertos aislados

“…utiliza una estrategia de modulación que modifica el ciclo de trabajo únicamente en el puerto que se conecta el supercapacitor. Se demuestra que esta estrategia permite operar el convertidor con ZVS en un amplio rango de variación de tensión (Purgat et al, 2020). Sin embargo, no se analizan las pérdidas totales del sistema y cuando se requiere aislar de potencia activa el puerto del supercapacitor (por ejemplo, cuando el mismo se encuentra descargado), la potencia reactiva del transformador puede aumentar considerablemente e incrementarse las pérdidas por conducción.…”