Virtual synchronous generator (VSG) is an important concept toward frequency stabilisation of the modern power system. The penetration of power electronic-based power generation in power grid reduces the total inertia, and thus increases the risk of frequency instability when disturbance occurs in the grid. VSG produces virtual inertia by injecting appropriate active power value to the grid when needed. This virtual inertia can stabilise the grid frequency in case of a power imbalance between generation and loads or any disturbances that affected frequency stability. Its intensive research can see the importance of VSG in inertia control and various intelligent controller techniques. Owing to the importance of VSG in the modern power grid, this study provides a comprehensive review on the control and coordination of VSG toward grid stabilisation in terms of frequency, voltage and oscillation damping during inertia response. A review on the type of energy storage system used for VSG and their benefits is also presented. Finally, perspective on the technical challenges and potential future research related to VSG is also discussed in this study. Nomenclature P g measured active power Q g measured reactive power P * active power reference Q* reactive power reference V g * output voltage reference V g output voltage ω o reference angular frequency ω g grid Frequency ω r rotor angular frequency J moment of inertia constant D damping coefficient constant δ VSG phase angle X output reactance of the VSG K w governor proportional control gain K q reactive power proportional control gain T Q reactive power first-order lag time constant

The transverse rumble strip (TRS) is one of the methods used to improve the driver's alertness to its driving and reduce their speed. However, the presence of a TRS causes unevenness on the road surface and may result in ground vibration when heavy vehicles passes it. This ground vibration may cause discomfort to the people living adjacent to the road. Therefore, there is a need to evaluate the level of ground vibration resulting from heavy vehicles passing over TRS especially on typical federal road in Malaysia which contains high percentage of fast-moving heavy vehicles. Ground vibration assessment study was conducted at federal road of Kluang-Batu Pahat Road (FT050) by using existing heavy vehicles in the traffic stream as study samples. ICP accelerometer and computer software Dewesoft7 have been used to measure and analyse the level of vibration generated. The results indicate heavy vehicles at a speed of 50 km/h, 33 km/h and 24km/h generate ground vibration level of 1.24 mm/s, 2.30 mm/s and 0.76 mm/s respectively. Other factors such as the weight of the heavy vehicles may involve in ground vibration generation mechanism as the results shown that there was no direct correlation between vehicle speed and level of ground vibration. All the generated ground vibration levels were found to be within the allowable limit set by Department of Environment Malaysia (DOE) standard guidelines.

To achieve a more sustainable supply of electricity and reduce dependency on fuels, the application of renewable energy sources-based distribution systems (DS) is stimulating. However, the intermittent nature of renewable sources reduces the overall inertia of the power system, which in turn seriously affects the frequency stability of the power system. A virtual synchronous generator can provide inertial response support to a DS. However, existing active power controllers of VSG are not optimized to react to the variation of frequency changes in the power system. Hence this paper introduces a new controller by incorporating GA-ANFIS in the active power controller to improve the performance of the VSG. The advantage of the proposed ANFIS-based controller is its ability to optimize the membership function in order to provide a better range and accuracy for the VSG responses. Rate of change of frequency (ROCOF) and change in frequency are used as the inputs of the proposed controller to control the values of two swing equation parameters, inertia constant (J) and damping constant (D). Two objective functions are used to optimize the membership function in the ANFIS. Transient simulation is carried out in PSCAD/EMTDC to validate the performance of the controller. For all the scenarios, VSG with GA-ANFIS (VOFIS) managed to maintain the DS frequency within the safe operating limit. A comparison between three other controllers proved that the proposed VSG controller is better than the other controller, with a transient response of 22% faster compared to the other controllers.