in simulation,while connecting a battery directly at the output of the boost converter, the battery is discharging the current during off period of mosfet switch instead of output capacitor of the boost converter. Is the intermittent charging and discharging of battery is allowed during a switching period?
Herewith i have attached the simulation circuit and waveform in jpeg format
It is clear from the circuit diagram you have a load resistance between the capacitor and battery. the discharge depends upon the voltage level of battery and capacitor. just check the voltages which ever is higher will discharge first. hope this may help you.
The battery can be connected directly to the output of the converter. What you observed is absolutely normal, since connecting the battery in parallel to the output of the converter, the output capacitor is charged to the battery voltage and, being its impedance (zero in the simulation) lower than that of the capacitor, the current flows through the battery rather than through the capacitor. This is what is observed in simulations, at least. In practice, the actual R-L impedance related to battery parasitics and to wiring, contacts, etc... connecting the battery to the boost converter can be easily higher, so most of the ripple current of the boost converter will actually flow through the capacitor.
Please also note that the converter can just charge the battery and not discharge it, since the diode prevents the current from flowing from the battery to the converter. In your diagram, the only element discharging the battery is the output resistor. Please also observe that the battery is discharged by such a resistor even when the converter is off and maybe this is not the expected behavior.
I would like to great all colleagues in this forum. Dr. Paolo analysed the circuit to underline its operating concepts. However, i would like to remember that the role of the boost converter is to raise the input voltage and also to match the input source to the load RL. So,the circuit operates as intended if it is resistive loaded.
Now you added a battery at the output. The battery will upset the functionality of the circuit since as hinted previously the battery is considered as a pure voltage source with zero resistance. Any current injected in the output side of the conveter will pass through the battery.charging it. After discharging the inductor in the battery the diode prevents reverse flow of current . The capacitor and the resistor have always the battery voltage as they are connected in parallel with it. So. the battery dominates the output of the converter and keeps its output voltage more or less fixed. This means that the output of the converter will be clamped at the battery voltage.
Batteries are devices that needs specific control when charging then. There is constant current charging , constant voltage charging or a combined technique.
The paper in the link may be useful to you:https://www.researchgate.net/publication/290436504_Enhancing_the_design_of_battery_charging_controllers_for_photovoltaic_systems
wish you sucess
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