Operation Of Power Conditioning System Research Articles

Centralized control of parallel connected power conditioning system in electric vehicle charge–discharge and storage integration station

This study presents a centralized control scheme that coordinates parallel operations of power conditioning system (PCS) for the grid interactions of electric vehicles (EVs) in EV charge–discharge and storage integration station. Key issues for the control and operation of PCS under various operation modes are discussed, including vehicle to grid (V2G) mode, stand-alone mode and seamless transfer mode. The intelligent multi-mode charge–discharge method is utilized for the V2G mode, and the parallel control method based on communication network is adopted for the stand-alone mode. In addition, a novel seamless transfer strategy is proposed, which is able to implement PCS transition between V2G mode and stand-alone mode. The detailed process of the seamless transfer between the two modes is illustrated. Experimental results are presented to show the performance and feasibility of this strategy.

Maximum Power Transfer Tracking for Ultralow-Power Electromagnetic Energy Harvesters

This paper describes the design and operation of power conditioning system with maximum power transfer tracking (MPTT) for low-power electromagnetic energy harvesters. The system is fully autonomous, starts up from zero stored energy, and actively rectifies and boosts the harvester voltage. The power conditioning system is able to operate the harvester at the maximum power point against varying excitation and load conditions, resulting in significantly increased power generation when the load current waveform has a high peak-to-mean ratio. First, the paper sets out the argument for MPTT, alongside the discussion on the dynamic effects of varying electrical damping on the mechanical structure. With sources featuring stored energy, such as a resonant harvester, maximum power point control can become unstable in certain conditions, and thus, a method to determine the maximum rate of change of electrical damping is presented. The complete power conditioning circuit is tested with an electromagnetic energy harvester that generates 600 mV rms ac output at 870 μW under optimum load conditions, at 3.75 m·s-2 excitation. The digital MPTT control circuit is shown to successfully track the optimum operating conditions, responding to changes in both excitation and the load conditions. At 2 V dc output, the total current consumption of the combined ancillary and control circuits is just 22 μA. The power conditioning system is capable of transferring up to 70% of the potentially extractable power to the energy storage.

Dynamic behavior of a grid‐connected microgrid with power conditioning system

ABSTRACTThe principle concept of microgrid (MG) is to integrate loads and microsources into a controllable system to supply electric power and heat to the user. This study discussed the dynamic characteristics of a grid‐connected MG associated with power conditioning system (PCS) to regulate its power. The investigated system primarily consists of the grid, microsources, lumped static loads, and other components. Detailed models based on matlab/Simulink (MathWorks, headquarters in Natick, Massachusetts, U.S.A.) were developed to cater for the dynamic behavior of the system. Two operational modes were investigated: four‐quadrant operation of PCS and use of PCS to control the power of MG. Simulation results suggest this MG can operate satisfactorily in these operational modes. This study can serve as an important reference for planning and operation of MGs. Copyright © 2013 John Wiley & Sons, Ltd.