# High Power Density, High-Voltage Parallel Resonant Converter Using Parasitic Capacitance on the Secondary Side of a Transformer

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## Abstract

**:**

## 1. Introduction

## 2. Proposed Parallel Resonant Converter

#### 2.1. Structure of the Proposed Parallel Resonant Converter

#### 2.2. Operating Principle

## 3. Analysis of Equivalent Circuit of the Proposed Parallel Resonant Converter

## 4. Analysis of the Secondary Side Voltage Multiplier

## 5. Experimental Results

## 6. Conclusions

## Author Contributions

## Funding

## Conflicts of Interest

## References

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**Figure 1.**System structure of the parallel resonant converter applied with a voltage multiplier: (

**a**) conventional system structure; (

**b**) proposed system structure.

**Figure 2.**Operation mode of the proposed parallel resonant converter: (

**a**) MODE 1 $\left[{t}_{0}-{t}_{1}\right]$; (

**b**) MODE 2 $\left[{t}_{1}-{t}_{2}\right]$; (

**c**) MODE 3 $\left[{t}_{2}-{t}_{3}\right]$; (

**d**) MODE 4 $\left[{t}_{3}-{t}_{4}\right]$.

**Figure 7.**(

**a**) Voltage at the secondary side of the transformer. (

**b**) Voltage after 1st voltage multiplier. (

**c**) Voltage after 4th voltage multiplier.

**Figure 9.**Experimental test waveforms; (

**a**) gate input voltage ${V}_{gs}$ and switching drain–source voltage ${V}_{ds}$; (

**b**) resonant inductor current ${I}_{Lr}$ at full-load condition; (

**c**) resonant inductor current ${I}_{Lr}$ at half-load condition.

Symbol | Quantity | Value (Unit) |
---|---|---|

${V}_{in}$ | Input voltage | 385 (V) |

${V}_{out}$ | Rated output voltage | 100 (kV) |

${P}_{out}$ | Rated output power | 1.7 (kW) |

${I}_{out}$ | Output current | 1.7 (mA) |

${L}_{r}$ | Resonant inductor | 106 (μH) |

${L}_{m}$ | Magnetizing inductance | 1000 (μH) |

${C}_{p}$ | Parasitic capacitance | 0.134 (nF) |

${n}_{1}:{n}_{2}$ | Turns ratio | 1:12 |

${f}_{s}$ | Switching frequency | 98 (kHz) |

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**MDPI and ACS Style**

Kwon, J.; Kim, R.-Y.
High Power Density, High-Voltage Parallel Resonant Converter Using Parasitic Capacitance on the Secondary Side of a Transformer. *Electronics* **2021**, *10*, 1736.
https://doi.org/10.3390/electronics10141736

**AMA Style**

Kwon J, Kim R-Y.
High Power Density, High-Voltage Parallel Resonant Converter Using Parasitic Capacitance on the Secondary Side of a Transformer. *Electronics*. 2021; 10(14):1736.
https://doi.org/10.3390/electronics10141736

**Chicago/Turabian Style**

Kwon, Jaean, and Rae-Young Kim.
2021. "High Power Density, High-Voltage Parallel Resonant Converter Using Parasitic Capacitance on the Secondary Side of a Transformer" *Electronics* 10, no. 14: 1736.
https://doi.org/10.3390/electronics10141736