BATTERY CHARGING AND DISCHARGE CONTROL OF A HYBRID ENERGY SYSTEM USING MICROCONTROLLER
ABSTARCT :
This study aims to control charging and discharging the battery for hybrid energy systems. The control system works by selecting the right energy source to supply voltage to the load. And also this control system can regulate charging and discharging the battery automatically. The voltage source consists of two energy, namely from the battery and DC source. The control system that has been designed has the ability to choose the right DC source when the battery capacity is less than 80%. This system also has a good ability to choose a battery source when the battery reaches 100% capacity and the DC source has a voltage drop of more than 20%. This control system is equipped with excessive electric current protection so that the security level is high.
EXISTING SYSTEM :
• Due to the existence of uncontrolled stochastic uncertainties, it is difficult to implement an optimal approach to manage the output power ratio between the PV, BESS and utility grid.
• In this paper, the energy production from PV and BESS is prioritized to use for charging demand over grid energy.
• When the output power of PV system is enough to the EV charging demand, the excess power of PV system will be stored a certain amount of energy in the BESS for future use.
• If the charging demand is higher than the available power of PV, BESS will operating in the discharge mode to make up the difference amount of power.
• The main objective of the PMS actions is the control of the battery state-of-charge, which is estimated by using an accurate algorithm developed for this purpose: this feature represents one key aspect of the developed system compared to existing ones, as it allows limiting in an effective way the number of startup and shutdown maneuvers of the FC.
• The estimation of the battery state-of-charge is also a crucial parameter for the management of the energy flows in a standalone system equipped with multiple power supply and electrochemical batteries.
DISADVANTAGE :
• Hybrid transportation systems, unlike those in pure electric vehicles, cannot effectively utilize regenerative energy during braking.
• Low power density and fast degradation of the cells in the battery under high charging currents
• Even when using the battery management systems that directly control the charging and discharging rate, cell’s state of charge (SOC), voltage and temperature, the lifetime of the common electric vehicle batteries does not exceed 4–5 years.
• The electrical vehicles are less economical as the battery is the most expensive part of electric vehicle.
PROPOSED SYSTEM :
• A decentralized charging scheduling was proposed in, where utility company broadcasts the price and EVs choose their own charging profiles, instead of being instructed by a centralized infrastructure, to achieve the objective of valley filling.
• Recognizing the emerging need for planning EVCS to satisfy the increasing charging demand from EVs, in this paper a framework was proposed to optimize the size of EVCS incorporating many uncertainties.
• Various energy management approaches have been proposed in the literature in order to handle the characteristics of different power generators and storage systems.
• The proposed real-time EMS is formulated based on optimization model for cluster of prosumers such that cooperative operation with other prosumers in the neighbourhood achieves balanced distribution and hence improved utilization rate.
• The proposed method helps the battery of EV to operate in a safer zone.
ADVANTAGE :
• The main issue is to avoid grid interruptions when several EVs are simultaneously plugged into the system during very short period of time can be solved by implementing this technique.
• It is envisaged that more sophisticated energy management system is required to manage the charging stations for large number of EVs. So by implementing this technique it is possible to overcome this problem up to some extent.
• The proposed technique optimizes the EV charging based on the availability of the PV power, real time electricity demand and tariff structures.
• This system leads to the safe charging of the battery that needs to be maintained to ensure long life of the EV batteries.
• Maintenance cost will be negligible when compared to IC Engine vehicles.
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