Dahai Zhang

Title: Inventor Profile: Dahai Zhang from Beijing

Introduction

Dahai Zhang is a prominent inventor based in Beijing, China, known for his contributions to electrical engineering, particularly in the field of modular multilevel converters and DC transmission networks. With a total of three patents to his name, his innovations have significantly enhanced the efficiency and reliability of electrical systems.

Latest Patents

Dahai Zhang’s latest innovations include two groundbreaking patents:

1. **Method for Protecting DC Line Impedance Phase Based on Protection and Control Coordination**

This patent presents a novel approach to protecting the impedance phase of DC lines within three-terminal flexible DC transmission networks. The method capitalizes on the high controllability of converters post-fault to inject characteristic signals at specific frequencies. By calculating the phase angle of input impedance, the method effectively identifies fault intervals, resulting in improved protection performance. This innovative approach transitions the protection strategy from passive to active and is resilient against the nonlinearity of converters. Furthermore, it enhances the speed of fault identification and offers economic advantages without necessitating additional equipment or compromising the entire system during a single line failure.

2. **Steady State Fault Current Calculation Method for Modular Multilevel Converter**

This method focuses on accurately calculating the steady-state fault current in modular multilevel converters (MMCs). It involves determining the critical resistance values based on various operational modes and calculating both DC and AC fault currents without considering AC side resistance. This methodology ensures precise fault current assessments and contributes to the safe operation of electrical systems under various conditions.

Career Highlights

Dahai Zhang is affiliated with Beijing Jiaotong University, where he has been integral to advancing research in electrical systems and sustainable energy solutions. His work is characterized by a commitment to innovation and practicality, reflecting his deep understanding of the challenges faced in modern electrical engineering.

Collaborations

Throughout his career, Dahai Zhang has collaborated with talented colleagues, including Meng Li and Jinghan He. These partnerships have fostered an environment of innovation and knowledge sharing, leading to significant advancements in their shared field.

Conclusion

Dahai Zhang's contributions to electrical engineering, particularly his patents addressing DC transmission and modular multilevel converters, showcase his innovative spirit and dedication to improving technology. Through his work at Beijing Jiaotong University and collaborations with fellow researchers, he continues to make impactful strides in the field, paving the way for future advancements in electrical systems.