Optimization of CHB-STATCOM Power Ramp Given Response Time with Capacitance Reduction

Huaen Zhang

doi:10.62051/ijmee.v5n2.05

Authors

Huaen Zhang

DOI:

https://doi.org/10.62051/ijmee.v5n2.05

Keywords:

CHB-STATCOM, Dc-side Voltage Phase-to-phase Unbalance, Power Asymptote, Power Jump Time

Abstract

The capacitance-reduced H-bridge cascaded static synchronous compensator (CHB-STATCOM) uses ramp feedforward to suppress the phase-to-phase voltage unbalance of the dc-side voltage when the compensated power jumps, and its minimum transition time T is 10ms, which fails to satisfy the shortest transition time T is 10ms, which cannot meet the demand of fast response of the device. To address this problem, this paper gives the relationship between the commanded power tapering time T less than 10ms and the inter-phase DC voltage based on the CHB-STATCOM control principle of capacitance reduction. The equations on increasing the DC component under the constraints of the upper and lower boundary constraints are developed and the upper and lower boundary constraints are taken into account under the constraints of the CHB-STATCOM operating principle of decreasing capacitance value .According to the characteristics of the constraint equations, a method for solving the constraint equations is proposed, and the solution results are analyzed by specific examples. The effectiveness of the method in improving the response time is verified by simulation with MATLAB software. The conclusions of the study can also provide a reference for the device to select the power jump time.

References

[1] A. Darvishzadeh, H. Iman-Eini and Y. Neyshabouri, "Diagnosis and Ride Through of Single-Switch Open-Circuit Fault in Low-Capacitance STATCOM," in IEEE Transactions on Power Electronics, vol. 40, no. 1, pp. 1952-1963.

[2] H. Wang, R. Qiu, J. Wu, M. Ma, F. Li and X. Zhang, "Online Capacitor Condition Monitoring for Cascaded-H-Bridge Type Converters," in IEEE Transactions on Power Electronics, vol. 39, no. 10, pp. 12514-12522.

[3] Y. Neyshabouri and H. Iman-Eini, "A New Fault-Tolerant Strategy for a Cascaded H-Bridge Based STATCOM," in IEEE Transactions on Industrial Electronics, vol. 65, no. 8, pp. 6436-6445.

[4] Rodriguez E,et al.Enhancing Inductive Operation of Low-Capacitance Cascaded H-Bridge StatComs Using Optimal Third-Harmonic Circulating Current[J].IEEE Transactions on Power Electronics,2021,36(9):10788-10800.

[5] Wang H,Blaabjerg F.Reliability of capacitors for DC-Link applications in power electronic converters-an overview[J].IEEE Transactions on Industry Applications,2014,50(5):3569-3578.

[6] Liu Q,Rodriguez E,Farivar G ,et al.Discontinuous Modulation of a Cascaded H-Bridge Low-Capacitance StatCom[J].IEEE Transactions on Power Electronics,2022,37(3):2790-2800.

[7] Isobe T,Zhang L,Tadano H,et al.Control of DC-capacitor peak voltage in reduced capacitance single-phase STATCOM [C].2016 IEEE 17th Workshop on Control and Modeling for Power Electronics (COMPEL), Trondheim, Norway, 2016:1-8.

[8] G. Farivar et al., “Load adaptive cascaded H-bridge low capacitance statcom with modular capacitors,” in Proc. 45th Ann. Conf. IEEE Ind. Electron. Soc., Lisbon, Portugal, 2019, pp. 3541–3546.

[9] Isobe T, Shiojima D, Kato K, et al. Full-Bridge reactive power compensator with minimized equipped capacitor and its application to static var compensator[J]. IEEE Transactions on Power Electronics, 2015, 31(1): 224-234.

[10] X. Ge and F. Gao, "Flexible Third Harmonic Voltage Control of Low Capacitance Cascaded H-Bridge STATCOM," in IEEE Transactions on Power Electronics, vol. 33, no. 3, pp. 1884-1889.

[11] Isobe T,Zhang L,Tadano H,et al.Control of DC-capacitor peak voltage in reduced capacitance single-phase STATCOM [C].2016 IEEE 17th Workshop on Control and Modeling for Power Electronics (COMPEL), Trondheim, Norway,2016:1-8.

[12] Farivar G,Hredzak B,Agelidis V G.Reduced-Capacitance Thin-Film H-Bridge Multilevel STATCOM Control Utilizing an Analytic Filtering Scheme[J].IEEE Transactions on Industrial Electronics,2015,62(10):6457-6468.

[13] Rodriguez E,Leyva R,Townsend D,et al.Closed-Loop Analytic Filtering Scheme of Capacitor Voltage Ripple in Multilevel Cascaded H-Bridge Converters[J].IEEE Transactions on Power Electronics,2020,35(8):8819-8832

[14] CHEN H C, CHENG PT. A DC bus voltage balancing technique for the cascaded H-bridge STATCOM with improved reliability under grid faults [J]. IEEE Transactions on Industry Applica-tions, 2017,53(2):1263.

[15] D. Lu, S. Wang, J. Yao, T. Yang and H. Hu, "Cluster Voltage Regulation Strategy to Eliminate Negative-Sequence Currents Under Unbalanced Grid for Star-Connected Cascaded H-Bridge STATCOM," in IEEE Transactions on Power Electronics, vol. 34, no. 3, pp. 2193-2205.

[16] MAHAR JAN L,YAMAGISHI T,AKAGIH. Active-power control of individual converter cells for a battery energy storage system based on a multilevel cascade PWM converter[J].IEEE Transactions on Power Electronics, 2012, 27 (3): 1099.

[17] M. Akihiro, T. Mannen and T. Isobe, "Dynamic Performance Improvement of Model-Based Capacitor Voltage Control for Single-Phase STATCOM with Reduced Capacitance," 2021 IEEE Applied Power Electronics Conference and Exposition (APEC), Phoenix, AZ, USA, 2021, 2024-2029.

[18] DU Shaotong, LI Wei, ZHOU Juan, et al. Analysis and Suppression Mechanism for Clustered Voltage Imbalance Generated by Capacitance Reduction of CHB-STATCOM [J]. Power System Technology,2024,48(11):4628-4637.

[19] DU Shaotong, TAN Xingguo, ZHOU Juan. Capacitor Value Selection Analysis and DC Voltage Control for Cascaded H-Bridge STATCOM With Reduced Capacitance Value [J]. Power System Technology, 2019, 43(1):275-284.