A High-Power Density DC Converter for Medium-Voltage DC Distribution Networks
Abstract
:1. Introduction
2. Modular Combined DC Converter Topology Based on Buck-LLC Integration
3. SDBuck-LLC’s Operating Principle and Steady-State Analysis
3.1. Analysis of Working Mode and Working Principle
- (a)
- In stage 4 of mode Y2, the voltage applied at both ends of Lb is Vi-VCc, which is negative at this time, in a low demagnetization state, and ILb slowly decreases.
- (b)
- The deep excitation state time corresponding to stages 1, 2, and 3 is lengthened, and the resonant negative half-cycle corresponding to this period is also lengthened.
- (c)
- The deep demagnetization state time corresponding to stages 6 and 7 is shortened, and the resonant positive half-period corresponding to this period is also shortened.
3.2. Characteristics of DC Voltage Gain
3.3. Voltage Stress and Power Characteristics
3.4. Soft-Switching Characteristics
4. Experimental Verification
4.1. Experimental Prototype
4.2. Experimental Scheme
5. Conclusions
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
References
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Refs. | Voltage Stress | ZVS Ability | Tracking Performance |
---|---|---|---|
[9] | Medium | Poor | Poor |
[13] | Low | Medium | Good |
[20] | High | Medium | Medium |
[25] | Low | Medium | Good |
Proposed | Low | Good | Good |
Mode | 1 | 2 | 3 | 4 |
---|---|---|---|---|
X (0 < D1 ≤ 0.5) | 0 < φ ≤ D1 | D1 < φ ≤ 0.5 | 0.5 < φ ≤ D1 + 0.5 | D1 + 0.5 < φ ≤ 1 |
Y (0.5 < D1 ≤ 1) | 0 < φ ≤ D1–0.5 | D1–0.5 < φ ≤ 0.5 | 0.5 < φ ≤ D1 | D1 < φ ≤ 1 |
Parameters | Values | Parameters | Values |
---|---|---|---|
Input voltage (Vi) | 750 V~1430 V | Rated output power (Po*) | 6.25~7 kW |
Output voltage (Vo) | 400 V | Rated switching frequency (fsn) | 80 kHz |
Resonant inductor (Lr) | 14.3 μH | Transformer turns ratio (nT) | 1:1 |
Input capacitance (C1~C4) | 50 μF | Auxiliary inductors (La1, La2) | 180 μH |
Phase shift (φ) | 0.15 | Resonant inductor (Lb) | 75 μH |
Clamp capacitor (Cc) | 55 μF | Resonant capacitance (Cr) | 276.6 nF |
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Wan, D.; Zhou, Q.; Duan, X.; Zhu, J.; Li, J.; Zhou, H. A High-Power Density DC Converter for Medium-Voltage DC Distribution Networks. Electronics 2023, 12, 3975. https://doi.org/10.3390/electronics12183975
Wan D, Zhou Q, Duan X, Zhu J, Li J, Zhou H. A High-Power Density DC Converter for Medium-Voltage DC Distribution Networks. Electronics. 2023; 12(18):3975. https://doi.org/10.3390/electronics12183975
Chicago/Turabian StyleWan, Dai, Qianfan Zhou, Xujin Duan, Jiran Zhu, Junhao Li, and Hengyi Zhou. 2023. "A High-Power Density DC Converter for Medium-Voltage DC Distribution Networks" Electronics 12, no. 18: 3975. https://doi.org/10.3390/electronics12183975
APA StyleWan, D., Zhou, Q., Duan, X., Zhu, J., Li, J., & Zhou, H. (2023). A High-Power Density DC Converter for Medium-Voltage DC Distribution Networks. Electronics, 12(18), 3975. https://doi.org/10.3390/electronics12183975