Abstract
The control system of a doubly-fed adjustable-speed pumped-storage hydropower plant needs phase-locked loops (PLLs) to obtain the phase angle of grid voltage. The main drawback of a comb-filter-based phase-locked loop (CF-PLL) is the slow dynamic response. This paper presents a modified comb-filter-based phase-locked loop (MCF-PLL) by improving the pole-zero pattern of the comb filter, and gives the parameters’ setting method of the controller, based on the discrete model of MCF-PLL. In order to improve the disturbance resistibility of MCF-PLL when the power grid’s frequency changes, this paper proposes a frequency-adaptive modified, comb-filter-based, phase-locked loop (FAMCF-PLL) and its digital implementation scheme. Experimental results show that FAMCF-PLL has good steady-state and dynamic performance under distorted grid conditions. Furthermore, FAMCF-PLL can determine the phase angle of the grid voltage, which is locked when it is applied to a doubly-fed adjustable-speed pumped-storage hydropower experimental platform.
Highlights
Pumped-storage hydropower plants (PSHP) are the most widely-used energy storage technology for large-scale energy storage levels, as it has the characteristics of being rapid, effective, economical, and reliable [1,2]
In order to improve the dynamic response of comb filter (CF)-Phase-locked loops (PLLs), this paper proposes modified comb-filter-based phase-locked loop (MCF-PLL) by introducing N poles and one zero when the sampling order of CF is N
When FAMCF-PLL completes the grid voltage phase locked, the phase can be rewritten in the dq reference as: frame by using the park transformation ( δ = ωt + θ1 − θu ≈ 0, Equation (8)) can be simplified
Summary
Pumped-storage hydropower plants (PSHP) are the most widely-used energy storage technology for large-scale energy storage levels, as it has the characteristics of being rapid, effective, economical, and reliable [1,2]. Phase-locked loops (PLLs) are the most widely-used synchronization technique in the field of grid-connected power converters [6,7,8,9,10,11,12]. A major challenge of PLLs is how to quickly and accurately estimate the phase angle and frequency when the grid voltage is distorted. Quickly and accurately estimate the phase angle and frequency when the grid voltage is distorted To overcome this challenge, combining filtering techniques into the structure of PLLs has been. The adjustable-speed, pumped-storage power plant’s excitation control system, based on the VME bus, the VME bus, and experimental results, are presented in Section 4 to validate the theoretical studies.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
