Table 8 Comparison with AI methods.

From: Bayesian-optimized LSTM-DWT approach for reliable fault detection in MMC-based HVDC systems

Protection method

Detection-method

Feature selection

Noise immunity (dB)

Fault resistance withstanding ability

Sampling-rate

Pre-training settings

Complexity in training setup time

Other remarks

Average-recognition rate

Ref.37

ANN

DWT

High (18.0 dB)

High (350.0 Ω)

Medium

Trial and error

Medium

A generalized linear model to set up hyperparameters of a non-linear model causes miss-convergence at a small window length

90.61%

Ref.16

ANN

Voltages

Low

Low (50.0 Ω)

Low

Trial and error

High

Due to the large window length, response time is slow

94.35%

Ref.38

SVM

WT

Not mentioned

Low

High

Not mentioned

High

Do not discuss noise immunity in the complicated and dynamic environment of the MT-HVDC networks

92.92%

Ref.39

ANN

Fast FT

Low (50.0 dB)

Low (100.0 Ω)

Medium

Trial and error

Medium

An in-depth analysis of noise immunity is missing, and the fault resistance range is -0.01–100-Ω-

88.85%

Proposed methodology

Improved LSTM

Norm

High (20.0 dB)

High (480.0 Ω)

Medium

Optimal settings (BO)

Low

Due to the optimal training solution, it is less prone to miss-convergence at a small window length

99.04%