Abstract
A virtual oscillator (VO) based frequency-locked loop (FLL) is proposed to estimate the grid frequency ωg and added to the control algorithm of a virtual synchronous machine (VSM) in order to better dampen oscillations in a power system comprising VSMs. The VO present in the virtual capacitor is used to estimate the ripple frequency. Similarly, a very simple but effective approximation is proposed, which features first-order dynamics instead of second-order in the conventional FLL. The change of VSM is to add a VO to offer a local friction-damping torque. The effect of the damping torque on the rotor of a VSM is similar to the presence of local friction damping on the same axis. Assumed that the damping torque is proportional to the frequency difference of ω - ωg. Derive the damping torque Tvo based on the VO from the existing state variables of the fourth-order VSM model and its terminal voltages. Simulations and experiments verify the effectiveness of the proposed method in power oscillations damping.
| Original language | English |
|---|---|
| Pages (from-to) | 1303-1310 |
| Number of pages | 8 |
| Journal | IEEE Journal of Emerging and Selected Topics in Power Electronics |
| Volume | 12 |
| Issue number | 2 |
| Early online date | 6 Nov 2023 |
| DOIs | |
| Publication status | Published - Apr 2024 |
| Externally published | Yes |
Bibliographical note
Publisher Copyright:© 2013 IEEE.
Funding
This work was supported in part by the Natural Sciences and Engineering Research Council of Canada (NSERC); in part by the Israeli Ministry of Infrastructure, Energy and Water, under Grant 219-11-128; and in part by the Israel Science Foundation under Grant 2802/21.
Keywords
- Low-frequency oscillation (LFO)
- synchronverter
- virtual oscillator (VO)
- virtual synchronous machine (VSM)