# The Power System and Microgrid Protection--A Review
## 3 Protection Scheme of Microgrid
### Adaptive Protection
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Refs.** & **Published Year** & **Main Contribution** \\ \hline [PERSON] and [PERSON] [56] & 2015 & Using the AAT to suitable coordination of the recloser–fuse \\ [PERSON] et al. [74] & 2015 & Adopting the distance protection considering infeed current \\ [PERSON] et al. [111] & 2015 & AP scheme by using Thevenin equivalent parameters \\ [PERSON] et al. [112] & 2015 & Adaptive PS with ACO and GA \\ [PERSON] et al. [58] & 2016 & Algorithm for assessing the fuse-reclose protection coordination \\ [PERSON] and [PERSON] [89] & 2017 & Impedance PS with the CA \\ [PERSON] et al. [120] & 2017 & Optimal relay coordination with independent settings \\ [PERSON] et al. [24] & 2018 & Estimating HIF location with time-domain analysis \\ [PERSON] et al. [88] & 2018 & Fault locating using current and voltage at the beginning of feeder and DG terminal \\ [PERSON] et al. [105] & 2018 & Harmonic-based OC relay by using injecting harmonic signals \\ [PERSON] [113] & 2018 & AP scheme with AMPL based IPOPT solver \\ [PERSON] et al. [25] & 2019 & MDL-based algorithm, HIF detection \\ [PERSON] et al. [30] & 2019 & Adding recloser to protect the blind areas \\ [PERSON] [38] & 2019 & FD with WT and avoiding malfunction of differential protection \\ [PERSON] et al. [47] & 2019 & Using the DOC to avoid the false tripping of the adjacent feeder \\ [PERSON] and [PERSON] [51] & 2019 & Using current-only polarity comparison \\ [PERSON] and [PERSON] [98] & 2019 & Using communication-assisted in OC protection scheme \\ [PERSON] et al. [119] & 2019 & The PS based on PnP with the CA, numerical relays \\ [PERSON] et al. [49] & 2020 & Using single-setting and dual-setting DOCRs \\ [PERSON] and [PERSON] [50] & 2020 & Using a dual-DOC relay to protect the microgrid \\ [PERSON] et al. [68] & 2020 & Using OC relay based on LVRT operation and relay settings \\ [PERSON] et al. [69] & 2020 & Improved OC relay based on compound fault acceleration factor \\ [PERSON]. [82] & 2020 & Protection scheme based on autocorrelation of current envelopes \\ [PERSON] and [PERSON] [83] & 2020 & Using a hybrid method by pulsating signal generator and DWT \\ [PERSON] et al. [93] & 2020 & In ungrounded LVDC \\ [PERSON] and [PERSON] [94] & 2020 & Using the fault location scheme of CPL in a dc microgrid \\ [PERSON] [99] & 2020 & Using seamless Transition islanding and grid synchronization in \\ [PERSON] et al. [116] & 2020 & PCC \\ [PERSON] et al. [122] & 2020 & Using a method based on the equivalent circuit \\ [PERSON] et al. [122] & 2020 & Protection technique using Time-time -transform and DBN \\ [PERSON] et al. [123] & 2020 & Using optimal coordination of DOC by GA \\ \hline Minimum Description Length (MDL); Nearest Neighbor Rule (NNR); Fault Detection (FD); Adaptive Protection (AP); Differential Scheme (DS); Automatic Analysis Tool (AAT); Main and Backup Protection (MBP); Power Line Carrier (PLC); Traveling Wave (TW); Mathematical Morphology (MM); Discrete Fourier Transform (DFT); Microgrid Protection Relay (MPR); Linear Programming Technique (LPT); Deep Belief Network (DBN); Plug and Play (PnP); Protection Scheme (PS); Communication-Assisted (CA). \\ \hline \hline \end{tabular}
\end{table} 
Table 2: _Cont._  
\begin{table}
\begin{tabular}{p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt}} \hline \hline
**Protection Scheme** & **Used Devices** & **Operation Method** & & **Advantages** & **Disadvantages** \\ \hline Current based (Conventional) & OC & Current symmetrical component component & • Simple & • Difficult to coordinate in the meshed distribution system. Inexpensive & • Problems with unsymmetrical loads due to the single-phase DCs \\ Current based (Modification) & DOC & Current symmetrical component component & • Easy to coordinate in the meshed distribution system. Selective & • More expensive than OC \\ FCL & Current transient component & • Reduction of the short circuit current & • Costly & •