In a DC/AC microgrid system,the issues of DC bus voltage regulation and power sharing have been the subject of a significant amount of research.Integration of renewable energy into the grid involves multiple converter...In a DC/AC microgrid system,the issues of DC bus voltage regulation and power sharing have been the subject of a significant amount of research.Integration of renewable energy into the grid involves multiple converters and these are vulnerable to perturbations caused by transient events.To enhance the flexibility and controllability of the grid connected converter(GCC),this paper proposes a common DC bus voltage maintenance and power sharing control strategy of a GCC for a DC/AC microgrid.A maximum power point tracking algorithm is employed to enhance the power delivered by the wind turbine and photovoltaic module.The proposed control strategy consists of primary and secondary aspects.In the primary layer control,the DC bus voltage is regulated by the GCC.In the secondary layer,the DC bus voltage is maintained by the energy storage device.This ensures reliable power for local loads during grid failures,while power injection to the grid is controlled by an en-ergy management algorithm followed by reference gen-eration of inductor current in the GCC.The proposed control strategy operates in different modes of DC voltage regulation,power injection to the grid and a hybrid operating mode.It provides wide flexible control and ensures the reliable operation of the microgrid.The proposed and conventional techniques are compared for a 15.8 kW DC/AC microgrid system using the MATLAB/Simulink environment.The simulation results demonstrate the transient behaviour of the system in different operating conditions.The proposed control technique is twice as fast in its transient response and produces less oscillation than the conventional system.展开更多
Power&signal multiplex transmission(P&SMT)is a technique that uses power electronic circuits for communication signal transmission.In this paper,a three-phase cascaded multilevel inverter-based P&S MT syst...Power&signal multiplex transmission(P&SMT)is a technique that uses power electronic circuits for communication signal transmission.In this paper,a three-phase cascaded multilevel inverter-based P&S MT system is proposed.The proposed method can transmit communication signals without using a Controller Area Network bus,thereby reducing the wiring cost of the conventional electric vehicle(EV)communication system.The designed system can achieve motor speed regulation and battery balance discharging for EVs.With the combined pulse width modulation scheme and frequency shift keying method,both power and communication signals are transmitted successfully in a simulation model implemented in Matlab/Simulink.By evaluating the bit error rate of the transmitted signal,the maximum signal rate of the proposed system is determined as 600 bit/s.展开更多
The modular multilevel converter(MMC)is a promising topology for medium-voltage drive applications due to its high-quality output waveforms,low device switching frequency and voltage rating.However,the large cell capa...The modular multilevel converter(MMC)is a promising topology for medium-voltage drive applications due to its high-quality output waveforms,low device switching frequency and voltage rating.However,the large cell capacitor voltage ripple is a severe challenge faced by MMC at low motor speeds.Recently,a hybrid MMC(HMMC)topology is proven to be a competitive solution because of its lower cell capacitor voltage ripple and not demonstrating a common-mode voltage(CMV)problem compared with other methods.However,the DC-link switch with IGBT limits HMMC from being applied in highvoltage applications.This paper uses a thyristor instead of IGBT as the DC-link switch.To ensure the thyristor can be softly turned on and safely turned off,a new control scheme is proposed.When using this proposed scheme,HMMC can also tolerate the failure of the thyristor being turned-off without shutting down the system,effectively improving its reliability.The cell capacitor voltage ripple analysis is presented considering the effects of the thyristor switching process.In addition,a decoupled energy balancing control is utilized to suppress the fluctuation of the DC current.Experimental results obtained from a 380 V/7.5 kW downscaled prototype validate the effectiveness of starting up a motor from the standby mode to rated speed applying full-torque.展开更多
In a DC/AC microgrid system,the issues of DC bus voltage regulation and power sharing have been the subject of a significant amount of research.Integra-tion of renewable energy into the grid involves multiple converte...In a DC/AC microgrid system,the issues of DC bus voltage regulation and power sharing have been the subject of a significant amount of research.Integra-tion of renewable energy into the grid involves multiple converters and these are vulnerable to perturbations caused by transient events.To enhance the flexibility and controllability of the grid connected converter(GCC),this paper proposes a common DC bus voltage maintenance and power sharing control strategy of a GCC for a DC/AC microgrid.A maximum power point tracking algorithm is employed to enhance the power delivered by the wind turbine and photovoltaic module.The proposed control strategy consists of primary and secondary as-pects.In the primary layer control,the DC bus voltage is regulated by the GCC.In the secondary layer,the DC bus voltage is maintained by the energy storage device.This ensures reliable power for local loads during grid failures,while power injection to the grid is controlled by an en-ergy management algorithm followed by reference gen-eration of inductor current in the GCC.The proposed control strategy operates in different modes of DC voltage regulation,power injection to the grid and a hybrid op-erating mode.It provides wide flexible control and en-sures the reliable operation of the microgrid.The pro-posed and conventional techniques are compared for a 15.8 kW DC/AC microgrid system using the MATLAB/Simulink environment.The simulation results demonstrate the transient behaviour of the system in different operating conditions.The proposed control technique is twice as fast in its transient response and produces less oscillation than the conventional system.Index Terms—Wind energy,photovoltaic energy,DC/AC microgrid,battery energy storage system,co-ordinated control.展开更多
基金supported by Prince Sultan University,Riyadh,Saudi Arabia,under research grant SEED-2022-CE-95.
文摘In a DC/AC microgrid system,the issues of DC bus voltage regulation and power sharing have been the subject of a significant amount of research.Integration of renewable energy into the grid involves multiple converters and these are vulnerable to perturbations caused by transient events.To enhance the flexibility and controllability of the grid connected converter(GCC),this paper proposes a common DC bus voltage maintenance and power sharing control strategy of a GCC for a DC/AC microgrid.A maximum power point tracking algorithm is employed to enhance the power delivered by the wind turbine and photovoltaic module.The proposed control strategy consists of primary and secondary aspects.In the primary layer control,the DC bus voltage is regulated by the GCC.In the secondary layer,the DC bus voltage is maintained by the energy storage device.This ensures reliable power for local loads during grid failures,while power injection to the grid is controlled by an en-ergy management algorithm followed by reference gen-eration of inductor current in the GCC.The proposed control strategy operates in different modes of DC voltage regulation,power injection to the grid and a hybrid operating mode.It provides wide flexible control and ensures the reliable operation of the microgrid.The proposed and conventional techniques are compared for a 15.8 kW DC/AC microgrid system using the MATLAB/Simulink environment.The simulation results demonstrate the transient behaviour of the system in different operating conditions.The proposed control technique is twice as fast in its transient response and produces less oscillation than the conventional system.
文摘Power&signal multiplex transmission(P&SMT)is a technique that uses power electronic circuits for communication signal transmission.In this paper,a three-phase cascaded multilevel inverter-based P&S MT system is proposed.The proposed method can transmit communication signals without using a Controller Area Network bus,thereby reducing the wiring cost of the conventional electric vehicle(EV)communication system.The designed system can achieve motor speed regulation and battery balance discharging for EVs.With the combined pulse width modulation scheme and frequency shift keying method,both power and communication signals are transmitted successfully in a simulation model implemented in Matlab/Simulink.By evaluating the bit error rate of the transmitted signal,the maximum signal rate of the proposed system is determined as 600 bit/s.
基金This work was supported by the National Natural Science Foundation of China under Grant 51720105008 and 52177173。
文摘The modular multilevel converter(MMC)is a promising topology for medium-voltage drive applications due to its high-quality output waveforms,low device switching frequency and voltage rating.However,the large cell capacitor voltage ripple is a severe challenge faced by MMC at low motor speeds.Recently,a hybrid MMC(HMMC)topology is proven to be a competitive solution because of its lower cell capacitor voltage ripple and not demonstrating a common-mode voltage(CMV)problem compared with other methods.However,the DC-link switch with IGBT limits HMMC from being applied in highvoltage applications.This paper uses a thyristor instead of IGBT as the DC-link switch.To ensure the thyristor can be softly turned on and safely turned off,a new control scheme is proposed.When using this proposed scheme,HMMC can also tolerate the failure of the thyristor being turned-off without shutting down the system,effectively improving its reliability.The cell capacitor voltage ripple analysis is presented considering the effects of the thyristor switching process.In addition,a decoupled energy balancing control is utilized to suppress the fluctuation of the DC current.Experimental results obtained from a 380 V/7.5 kW downscaled prototype validate the effectiveness of starting up a motor from the standby mode to rated speed applying full-torque.
基金supported by Prince Sultan University,Riyadh,Saudi Arabia,under research grant SEED-2022-CE-95.
文摘In a DC/AC microgrid system,the issues of DC bus voltage regulation and power sharing have been the subject of a significant amount of research.Integra-tion of renewable energy into the grid involves multiple converters and these are vulnerable to perturbations caused by transient events.To enhance the flexibility and controllability of the grid connected converter(GCC),this paper proposes a common DC bus voltage maintenance and power sharing control strategy of a GCC for a DC/AC microgrid.A maximum power point tracking algorithm is employed to enhance the power delivered by the wind turbine and photovoltaic module.The proposed control strategy consists of primary and secondary as-pects.In the primary layer control,the DC bus voltage is regulated by the GCC.In the secondary layer,the DC bus voltage is maintained by the energy storage device.This ensures reliable power for local loads during grid failures,while power injection to the grid is controlled by an en-ergy management algorithm followed by reference gen-eration of inductor current in the GCC.The proposed control strategy operates in different modes of DC voltage regulation,power injection to the grid and a hybrid op-erating mode.It provides wide flexible control and en-sures the reliable operation of the microgrid.The pro-posed and conventional techniques are compared for a 15.8 kW DC/AC microgrid system using the MATLAB/Simulink environment.The simulation results demonstrate the transient behaviour of the system in different operating conditions.The proposed control technique is twice as fast in its transient response and produces less oscillation than the conventional system.Index Terms—Wind energy,photovoltaic energy,DC/AC microgrid,battery energy storage system,co-ordinated control.