Ziheng Xiao

Ziheng Xiao

Hunan University

H-index: 5

Asia-China

About Ziheng Xiao

Ziheng Xiao, With an exceptional h-index of 5 and a recent h-index of 5 (since 2020), a distinguished researcher at Hunan University, specializes in the field of Power Electronics.

His recent articles reflect a diverse array of research interests and contributions to the field:

A Hybrid Data-driven Power Loss Minimization Method of Dual Active Bridge Converters

Current Balancing Control Method with Reduced Number of Current Sensors for Interleaved LLC Converters

A Data-Driven Control Parameters Optimization Method for Dual Active Bridge Converters

Seamless Rotational Phase Shedding for Multiphase DC-DC Converters

Refining Power Converter Loss Evaluation: A Transfer Learning Approach

A Zero-knowledge ANN-based Waveform and Critical Parameter Calculator for Resonant Converters

Full-Range ZVS Control Method Based on Near-CRM for T-Type Three-Level Inverter

Efficiency Improvement of DAB Converters with Enhanced Inductor Current Classification

Ziheng Xiao Information

University

Hunan University

Position

___

Citations(all)

48

Citations(since 2020)

48

Cited By

2

hIndex(all)

5

hIndex(since 2020)

5

i10Index(all)

1

i10Index(since 2020)

1

Email

University Profile Page

Hunan University

Ziheng Xiao Skills & Research Interests

Power Electronics

Top articles of Ziheng Xiao

A Hybrid Data-driven Power Loss Minimization Method of Dual Active Bridge Converters

Authors

Ziheng Xiao,Yu Jiang,Zhigang Yao,Zhou He,Yongbin Jiang,Yaohua Li,Yi Tang

Journal

IEEE Transactions on Power Electronics

Published Date

2024

Due to the intricate array of control parameters, achieving efficiency optimization for a typical dual active bridge (DAB) prototype becomes a laborious and time-intensive task. Traditional methodologies have revolved around an idealized lossless model of DAB, inevitably leading to a disparity between theoretical ideals and experimental realities. To surmount this challenge, we employ a hybrid data-driven model that seamlessly integrates insights derived from both simulation and experimentation. The disparity between the experimental and simulated models is represented as a residual branch, akin a nonlinear, dissipative impedance. This residual branch contributes to a fraction of power losses and subsequent output voltage/power reduction. The strategic minimization of residual branch emerges as a pivotal step in identifying the optimal control parameters. These optimal control parameters are then subjected to …

Current Balancing Control Method with Reduced Number of Current Sensors for Interleaved LLC Converters

Authors

Gang Luo,Zhigang Yao,Linglong Jiang,Ziheng Xiao,Weirong Chen,Yi Tang

Journal

IEEE Journal of Emerging and Selected Topics in Power Electronics

Published Date

2024/4/15

The multiphase interleaved LLC converter has gained significant popularity in high-power isolation applications. However, due to parameter tolerances, it requires multiple current sensors to balance the currents in parallel channels, thereby increasing sensor cost and hardware complexity. In this paper, a current balancing method with reduced number of current sensors for an interleaved LLC converter is proposed to achieve cost-effective current balancing. By introducing an initial phase-shift angle into the traditional variable frequency phase shift control, the total rectifier output current of the interleaved LLC converter can be decoupled into two individual currents in all operating modes. The difference between the two individual currents is used to generate phase-shift angle compensation signals and then to implement the current balancing in parallel channels. As only one low ripple total current needs to be …

A Data-Driven Control Parameters Optimization Method for Dual Active Bridge Converters

Authors

Ziheng Xiao,Yu Jiang,Fei Deng,Zhigang Yao,Yi Tang

Journal

IEEE Transactions on Industrial Electronics

Published Date

2024/3/19

Conventional optimization approaches for dual active bridge converters (DAB) involve separate analysis and experimental verification stages, which may lead to suboptimal experiment results due to unaccounted parameters. This article presents a data-driven control parameters optimization method for DAB. The theoretical analysis and experimental verification of power loss serve as the source and target domains, respectively. By employing a large-scale set of simulation samples, we train an artificial neural network to evaluate power loss under various operating conditions. The insights gleaned from the pretrained source domain model are subsequently transferred to a target domain model (TDM) through transfer learning fine-tuning on a small scale of experiment samples. The TDM is utilized within a mathematical software to explore optimal control parameters, striking a balance between precision and …

Seamless Rotational Phase Shedding for Multiphase DC-DC Converters

Authors

Ziheng Xiao,Zhigang Yao,Fei Deng,Lei Zhang,Yi Tang

Journal

IEEE Transactions on Power Electronics

Published Date

2024/1/29

This letter proposes a seamless rotational phase shedding (PS) operating method designed for multiphase DC-DC converters. Utilizing a 15-kW/50 kHz three-phase interleaved synchronous boost converter as an example, the optimal activation of phases is determined by minimizing power losses. Through a comprehensive analysis of total inductor current sag and swell in both steady-state and dynamic rotational PS operation, the optimal pulse width modulation (PWM) switching patterns are identified. Experimental results demonstrate that the proposed method outperforms traditional approaches, seamlessly achieving rotational PS while preserving interleaved among different activated phases.

Refining Power Converter Loss Evaluation: A Transfer Learning Approach

Authors

Ziheng Xiao,Yu Jiang,Tengfei Sun,Yue Wu,Yi Tang

Journal

IEEE Transactions on Power Electronics

Published Date

2024/1/2

A precise evaluation of power converter losses is essential for accurately predicting power loss and optimizing control parameters to enhance efficiency across various scenarios and applications. Conventional power loss evaluation methods separate the theoretical analysis and experimental verification stages. Consequently, these methods often suffer from irreconcilable disparities between the analytical predictions and measurement outcomes. This article introduces a transfer learning (TL)-based refinement approach for power loss evaluation, which can be iteratively improved with ongoing experimental data. Our method entails the creation of an extensive source domain dataset for training a source domain model, followed by fine-tuning in the target domain. Consequently, a self-adaptive and refined power loss evaluation model is established with a small amount of experimental data. We conducted a case …

A Zero-knowledge ANN-based Waveform and Critical Parameter Calculator for Resonant Converters

Authors

Ziheng Xiao,Yu Jiang,Yongbin Jiang,Yi Tang

Published Date

2023

Despite the widespread use of resonant converters in various applications, their analysis and design still necessitate a solid comprehension of the converter's operating principle and nonlinear behavior, which can be a significant manpower burden. To alleviate this issue and free us from repetitive work, this paper proposes a zero-knowledge artificial neural network (ZANN)-based waveform and critical parameter calculator for resonant converters. A normalized resonant network is employed to generate adequate data for training the ZANN. The ZANN can identify the essential characteristics of different resonant networks based on the configuration of hyperparameters. The accuracy of the calculator is verified using a 3-kW 480-V CLLC prototype. The results show that the accuracy of the root-mean-square (RMS) values is less than 5%, while the accuracy for the peak values is less than 20%.

Full-Range ZVS Control Method Based on Near-CRM for T-Type Three-Level Inverter

Authors

Zhigang Yao,Xinyu He,Ziheng Xiao,Zhou He,Yongbin Jiang,Yi Tang

Published Date

2023/10/29

T-type inverter is attractive due to low conduction losses and low switching voltage, and small size of passive component. Usually, zero-voltage switching (ZVS) without auxiliary circuit can be easily achieved by controlling the inverter to operate in the near critical conduction mode (near-CRM). However, with conventional modulation, T-type inverter require an extremely low switching frequency to achieve near-CRM mode when the AC voltage crosses zero, which is impractical for the digital controller. This paper proposes a new third-mode based modulation method and a variable switching frequency control method to make the T-type inverter into near-CRM. The proposed method is able to make all switches achieve ZVS soft-switching at full-range operation. The effectiveness and performance of the proposed modulation and control are validated by an experimental prototype.

Efficiency Improvement of DAB Converters with Enhanced Inductor Current Classification

Authors

Ziheng Xiao,Lei Zhang,Zhixing He,Yi Tang

Published Date

2023/10/29

The inductor current plays an important role in dual active bridge converters (DAB) because the ohmic loss and the switching loss are related to the global and detailed characteristics of the inductor current. For most of the previous articles, these two characteristics are analyzed separately, and the DAB efficiency is not be considered comprehensively. This paper gives the operation stage trajectory (OST) analysis based on the intrinsic characteristic of DAB with triple-phase shift modulation scheme (TPS). A novel inductor current classification method considering both the global and detailed characteristics is proposed. On this basis, a reduced non-active current modulation scheme is proposed with a small amount of non-active current while extending the ZVS operation region. The experimental results obtained from the laboratory prototype are given to validate the practical feasibility of the proposed modulation …

Sensorless Simultaneous Self-Balance Mechanism of Voltage and Current Based on Near-CRM in Interleaved Three-Level DC-DC Converter

Authors

Zhigang Yao,Xinyu He,Ziheng Xiao,Zhou He,Weirong Chen,Shuai Lu,Yi Tang

Journal

IEEE Transactions on Power Electronics

Published Date

2023/11/7

Voltage and current balance are essential in an interleaved three-level dc–dc converter. In this article, a simultaneous voltage and current self-balance mechanism based on near-critical conduction mode (CRM) for an interleaved three-level dc–dc converter is discovered, which can realize current and voltage balancing automatically without sensors. First, the zero-voltage switching (ZVS) and resonance transition generated by near-CRM are analyzed in detail. Second, the actual equivalent duty cycle is formulated to disclose its relationship to the unbalanced capacitor voltages and unbalanced inductor currents. It is found that the additional equivalent duty cycles in near-CRM are created and affected by the resonance around the valley and peak currents, so that some feedback loops are naturally formed to adjust the unbalanced voltages and currents. Then, by constructing the 3D relationship and natural feedback …

Ultra-high Efficiency Wireless Power Transfer Systems Based on Novel Multi-variable Control Strategy

Authors

Yongbin Jiang,Yue Wu,Yaohua Li,Zhou He,Ziheng Xiao,Huajia Wang,Xiaohua Wang,Yi Tang

Published Date

2023/10/29

In this paper, an ultra-high efficiency wireless power transfer system (WPTS) with wide ranges of charging voltage, power and coupling coefficient of resonant coils is proposed. First, the mathematical model of the system transfer efficiency based on the novel multi-variable control strategy is derived to precisely analyze power losses of the WPTS. Second, a novel coordinated control strategy with four control variables is proposed to achieve ultra-high efficiency wireless energy transfer with wide voltage and power ranges without any auxiliary dc-dc converters. Third, the minimum power loss model of the WPTS is analyzed and built. Meanwhile, the minimum power loss points and their operating conditions are derived and summarized. Finally, compared with the traditional control method in the same cases, the WPTS with the proposed coordinated control strategy not only can achieve ZVS operation of all switches …

Computer-Aided Time Domain Operation and Design Optimization of Resonant Converters

Authors

Ziheng Xiao,Zongjian Li,Zhixing He,Hongliang Wang,Yi Tang,An Luo

Journal

IEEE Journal of Emerging and Selected Topics in Power Electronics

Published Date

2023/5/12

This article presents a method for computer-aided operation and design optimization of resonant converters using time-domain analysis. Resonant converters can operate in different operation stage trajectories (OSTs) with the change of two degrees of freedom (2DOFs), namely, switching frequency and duty ratio . This article calculates and analyzes the operation characteristics, zero-voltage switching-ON (ZVS-ON) region, and zero-current switching-OFF (ZCS-OFF) region when the 2DOFs vary by solving the OST differential equation sets. Based on this analysis, an algorithm is proposed to find the operation and design optimizations of a specific resonant converter while considering 2DOFs by traversing all possible control coordinates. This article provides several case studies to demonstrate the design tradeoffs in different scenarios, which are verified through experimental verifications.

Precise Modeling for the Inductance of Rounded Rectangular Coils in Wireless Power Transfer Systems

Authors

Yongbin Jiang,Yue Wu,Yaohua Li,Ziheng Xiao,Ning Wang,Min Wu,Xiaohua Wang,Yi Tang

Published Date

2023

This paper introduces a novel analytical model for the accurate inductance calculation of rounded rectangular coils in wireless power transfer systems (WPTSs). Comprehensive analysis is conducted for the rounded rectangular coil and a new parametric model is proposed to precisely define its structure. A new inductance calculation model is proposed for the rounded rectangular coils based on Neumann's formula and the obtained parametric structure model. The Geometric Mean Distance method is introduced to reduce the complexity and difficulty of self-inductance modeling. The image current method is adopted to achieve accurate inductance modeling for rounded rectangular coils with ferrite plates. Finally, the accuracy of the proposed analytical model is validated and compared with two other traditional methods. It turns out that the proposed models can achieve high calculation accuracy in self-inductance …

Power Loss Minimization of CLLC Resonant Converters via Time Domain Analysis

Authors

Ziheng Xiao,Zhou He,Fei Deng,Yi Tang

Published Date

2023/10/29

The symmetric CLLC resonant converter has distinguished potential in battery chargers and energy storage systems due to zero voltage switching-on (ZVS-on) and flexible control with multiple degrees of freedom. However, the widely used frequency domain analysis lacks accuracy, and most time domain analysis only considers pulse frequency modulation (PFM), which limits the efficiency of CLLC, especially in step-down and light load conditions. To fully exploit the potential of CLLC resonant converters, this paper conducts a time domain analysis to search for the two control variables: optimal switching frequency and duty ratio of CLLC, aiming to minimize power loss. Additionally, a closed-loop power loss minimization modulation is proposed based on this analysis. The effectiveness of the proposed method is verified through experimentation on a 3-kW 480-V CLLC prototype.

A Precise and Fast BPNN-Based Voltage Gain Model of CLLC Converters in All Operation Conditions

Authors

Ziheng Xiao,Yu Jiang,Zhigang Yao,Yi Tang

Published Date

2023

The CLLC resonant converters are widely used in data center, battery chargers, electrical vehicles due to its high efficiency and high power density. The voltage gain characteristic of CLLC resonant converters plays an important role in both operation analysis and design optimization. This paper presents a precise and fast backpropagation neural network (BPNN)-based voltage gain model of CLLC that considers two degrees of freedom (2DOFs), the switching frequency and duty ratio , in all operation conditions. The effectiveness of the model is verified by a 3-kW 480-V CLLC prototype. The voltage gain error is reduced by 95% compared to the conventional fundamental harmonic approximation (FHA) method, and the calculation burden is reduced by 99% compared to the time-domain method.

A Universal Coil Structure Design Method with Accurate Numerical Computation in Wireless Power Transfer Systems

Authors

Yue Wu,Yongbin Jiang,Yaohua Li,Zhou He,Chang Wang,Ziheng Xiao,Xiaohua Wang,Yi Tang

Published Date

2023/10/29

Conventional design and optimization methods for resonant coils in wireless power transfer systems (WPTSs) heavily rely on finite element simulations, which are very time-consuming and complex. In this paper, a novel Universal Coil Structure Design (UCSD) method is proposed to accelerate and optimize the design process of rounded rectangular coils in WPTSs. First, the analytical model of the resonant coil’s self-inductance is derived when no ferrite plate is added. Second, the image current method is adopted to calculate coil’s self-inductance when ferrite plates are added. Accurate numerical calculation methods are used for the derived analytical model to calculate the coil’s self-inductance quickly and precisely. Next, the working principle of the UCSD method is presented. The UCSD method can calculate the self-inductances of rectangular coils with the proposed analytical model and pinpoint the most …

Piecewise-Approximated Time Domain Analysis of LLC Resonant Converter Considering Parasitic Capacitors and Deadtime

Authors

Ziheng Xiao,Zhixing He,Renfeng Guan,An Luo

Journal

IEEE Transactions on Power Electronics

Published Date

2022/9/16

LLC resonant converters are widely used in high power density and high efficiency applications. Practically, the parasitic capacitors of mosfet s and diodes, the stray capacitor of the high frequency transformer, and the dead time will have a great impact not only on the steady state resonant waveforms but also on the zero voltage switching- on (ZVS- on ) of the mosfet s. This article presents a piecewise-approximated time domain analysis of LLC both considering the parasitic/stray capacitors and the dead time. On this basis, not only the accurate steady state resonant waveforms, but also the ZVS- on boundary can be obtained, which will guide the parameter design, and switching frequency/dead time configuration instead of slow and cumbersome simulations. The major applications of the presented analysis, including the resonant/switching waveform illustration, the critical dead time calculation, and the optimal …

Unified description and optimization method of dual active bridge DC–DC converters

Authors

Ziheng Xiao,Zhixing He,Zongjian Li,Lipeng Zhu,Lei Wang

Journal

IEEE Transactions on Power Electronics

Published Date

2022/5/23

The optimization of dual active bridge converters (DAB) is widely studied and numerous modulation schemes are proposed to enhance the performance of a DAB converter. However, a unified description method both suitable for time and frequency domain analysis still lacks. Besides, the optimization process encounters a difficulty of the potential nonconvex feasible region restricted by the power transmission equality, making the regular convex optimization methods no longer applicable. To solve these problems, this article gave a unified description method both suitable for time and frequency domain analysis based on the standard decomposition of instantaneous electric quantities. Besides, a unified optimization method is proposed based on tangent point searching for the feasible region and optimization objective surfaces. With the proposed unified optimization method, the optimization objective can be …

Analysis and design of a modular self-balance high-voltage input DC–DC topology

Authors

Ziheng Xiao,Zhixing He,Renfeng Guan,Zongjian Li,Qianming Xu,Yandong Chen,An Luo

Journal

IEEE Journal of Emerging and Selected Topics in Power Electronics

Published Date

2022/1/6

In high-voltage (HV) input to low-voltage (LV) output dc/dc conversion applications, the input series output parallel (ISOP) structure is widely used and studied. Practically, the ISOP system encounters the below challenges: 1) HV isolated components, such as the HV isolated and HV input extra auxiliary power supply (APS) and the HV isolated high-frequency transformers (HFTs); 2) the submodule (SM) input voltage-sharing (IVS) control must be applied as long as the system is running, and it requires the control system to be highly reliable; and 3) scarcity of simple and high-efficient startup process with commercial APSs. To overcome the above challenges and simplify the control system, this article gave analysis and design of a modular self-balance HV input dc/dc topology without HV isolated components. A detailed time-domain SM design method, as well as the -domain SM input impedance analysis of the …

双有源桥直流变换器相平面分析与优化

Authors

肖子衡,何志兴,陈峻岭,陈燕东,欧阳红林& 罗安

Published Date

2021

双有源桥 DAB (dual active bridge) 直流变换器的优化研究广泛, 调制方法众多, 然而, DAB 的优化过程有 2 个困难: 第 1 个是受制于传输功率的等式约束条件, 使得可行域存在非凸的可能性, 常规的凸优化方法可能会失效; 第 2 个是常用的优化目标表达式过于复杂, 所求得的控制坐标难以获得解析表达式. 为了解决这些问题, 采用了相对偏导增益法, 从而避免了可行域非凸的问题. 同时, 基于相平面分析方法得到了以电感电压有效值最小化的控制坐标解析表达式, 相比于以电感电流有效值最小化调制方法, 电感电压有效值最小化调制方法的效率与以电感电流有效值最小化调制方法的效率相当, 而且, 简单的控制坐标便于该调制方法的数字实现. 最终, 实验结果证实了相平面分析的正确性以及所提调制方法的可实现性.

A three-terminal submodule based high DC conversion ratio system with self-balance feature

Authors

Ziheng Xiao,Zhixing He,Renfeng Guan,Zongjian Li,Ben Zhou,An Luo

Journal

IEEE Transactions on Power Electronics

Published Date

2021/12/1

The input series output parallel (ISOP) and input parallel output series (IPOS) systems have been extensively researched and applied in academia and industry due to the high dc conversion ratio. Practically, the ISOP and IPOS systems faced challenges, such as relatively immature high-voltage (HV) isolated high-frequency transformer (HFT), high reliability on HV isolated control system, difficulties in the auxiliary power supply (APS), start-up process, and bypass circuit/strategy. To overcome the above-mentioned challenges without adding complexities, this article proposes the three-terminal submodule (3TSM) as the fundamental SM for high dc conversion ratio step-up/step-down applications. Thanks to the 3TSM, the system is with self-balance feature, HV isolated HFTs are unnecessary, the control system is simplified (no matter in open or closed loop). Besides, commercial APSs can be adopted directly to the …

See List of Professors in Ziheng Xiao University(Hunan University)

Ziheng Xiao FAQs

What is Ziheng Xiao's h-index at Hunan University?

The h-index of Ziheng Xiao has been 5 since 2020 and 5 in total.

What are Ziheng Xiao's top articles?

The articles with the titles of

A Hybrid Data-driven Power Loss Minimization Method of Dual Active Bridge Converters

Current Balancing Control Method with Reduced Number of Current Sensors for Interleaved LLC Converters

A Data-Driven Control Parameters Optimization Method for Dual Active Bridge Converters

Seamless Rotational Phase Shedding for Multiphase DC-DC Converters

Refining Power Converter Loss Evaluation: A Transfer Learning Approach

A Zero-knowledge ANN-based Waveform and Critical Parameter Calculator for Resonant Converters

Full-Range ZVS Control Method Based on Near-CRM for T-Type Three-Level Inverter

Efficiency Improvement of DAB Converters with Enhanced Inductor Current Classification

...

are the top articles of Ziheng Xiao at Hunan University.

What are Ziheng Xiao's research interests?

The research interests of Ziheng Xiao are: Power Electronics

What is Ziheng Xiao's total number of citations?

Ziheng Xiao has 48 citations in total.

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