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Inertial support for hybrid AC/DC microgrid systems is provided by the virtual synchronous generator (VSG). However, the fast performance of the system is neglected while enhancing the stability of the system. To address this problem, an adaptive virtual inertia control strategy based on VSG technology is proposed. This control approach adaptively adjusts the system virtual inertia when the system operation deviates from the nominal value, by slowing down the rate of change of AC frequency and DC voltage and improving the deviation of AC frequency and DC voltage. Meanwhile, when the AC frequency and DC voltage restore back to the rated value, the rate of change of AC frequency is accelerated and the DC voltage fluctuation is reduced by dynamically adjusting the virtual inertia of the system. The proposed adaptive virtual inertia control method combines the advantages of large and small inertia to effectively improve the dynamic response of the system voltage and frequency in both rectifier and inverter modes. Finally, the simulation and experimental results verify the effectiveness of the proposed control algorithm.

As the main force of new energy generation, photovoltaic power generation is widely used in microgrid. Considering the coordinated operation of photovoltaic and energy storage system (ESS) in the island operation mode, the control strategy of voltage stability and power balance was studied for the low-voltage DC microgrid composed of the distributed generations. When the loads of DC microgrid system change abruptly, the DC bus power will be excessive or deficient, which will affect the stability of bus voltage. In this paper, a parallel structure of ESS and photovoltaic cell was used, and a bidirectional DC/DC converter was used to connect the energy storage battery with the DC bus. Based on RBF neural network tuning PID control, an improved bidirectional DC/DC converter operation mode control algorithm was proposed. When the system load changed suddenly, the voltage stability and power balance of DC bus were realized simultaneously. The effectiveness of the proposed algorithm was verified by simulation.

The traditional communication technology between electric vehicles (EVs) and DC charging piles often causes problems such as low reliability, high cost of communication line and high maintenance cost. The power line communication (PLC) technology is a mature technology and has the advantages of simplifying charging cable, reducing cable cost, which has certain practicability and feasibility. This paper deeply analyzes the channel characteristics, noise characteristics and uses OFDM as transmission method for the PLC signal between EVs and DC charging piles. The bit error rate (BER) is a measure index in this paper, this paper calculates the BER under various working conditions in order to determine the performance of OFDM technology in the power line channel. The simulation results indicate that PLC technology based on OFDM could meet the communication demand between EVs and DC charging piles, which have some certain utilities.

Vehicular Power Line Communication (VPLC) reuses the vehicular power cables as communication medium, which avoids the need of additional vehicular communication line and optimize the in-vehicle space. However, there are some factors to impact VPLC can work reliability without problems. One of the challenges is the VPLC channel noise, which can cause the low reliability of communication. Hence, in this work, we built up three kind typical vehicular noise model and FSK module in Simulink, analysis the channel characteristics under different type noise based on FSK. Our simulation results demonstrate the feasibility of PLC under FSK modulation and demodulation type used in PEVs and could provide guidance to the implementation of VPLC in the practical engineering.

The parameter identification and the projective synchronization between spatiotemporal chaotic systems are studied. The parameter identification law and the adaptive law of undetermined function representing the coupling strength are designed based on Lyapunov theorem. Not only the unknown parameters in responses system are identified, but also projective synchronization between spatiotemporal chaotic systems is realized. The Burgers equation with spatiotemporal chaos behavior is further taken as an example of simulation analysis.

Anti-synchronization of complex network is investigated in which nodes are discrete spatiotemporal chaos systems with diverse structures. The form of the coupling functions connecting nodes in the complex network and the control gain are obtained through constructing an appropriate Lyapunov function. The spatially extended system of laser phase conjugate wave having spatiotemporal chaos behavior in physics, Gibbs electrical-optical spatiotemporal chaos model, Bragg acousto-optical spatiotemporal chaos model and the one-dimensional discrete convective equation are all taken as nodes of the complex network. Artificial results show that a stable anti-synchronization is obtained in the whole network.

The Plankton spatiotemporal chaos system is taken as network node and constructed as a rich-club network through nonlinear coupling. The synchronization of spatiotemporal chaos for the above network is investigated. The general selection rule of nonlinear coupling function connecting nodes in the rich-club network is presented. Furthermore, the condition to realize the network synchronization is analyzed theoretically based on Lyapunov stability theory. Finally, the synchronization effect of spatiotemporal chaos for the rich-club network is checked through artificial simulation. The results show that complete synchronization can be realized for all rich nodes in the rich-club network and all nodes in every subnetwork constructed in star-shape.

A method of chaos synchronization of a complex network with different nodes is proposed. The complex network is constructed by chaos systems with diverse structures. The coupling functions of the connected nodes of the complex network are identified based on Lyapunov stability theory. The Rssler system，Coullet system and Lorenz system are taken as network nodes of the complex network in the paper. Simulation results show that a stable synchronization is obtained in whole complex network. The method can achieve synchronization of the networks with nodes of any chaotic systems，and the number of the node does not affect the stability of the whole complex network，therefore，it has a universal application.

A parameter observer is designed to identify Rossler system with unknow parameters. Chaos synchronization between uncertain Rossler system and Coullet system is realized via backstepping method.The synchronization controller is presented based on stability theory, and the area of controlling gain is determined. The simulation results show that all the state variables in the Coullet system can track any desired trajectory in the Rossler system exactly when the parameter observer and backstepping controller are functioning, which shows the method is effective and feasible.