Hi Puneet,

1- CAN WE RUN A SOLAR SYSTEM WITHOUT BATTERY BANK FOR ONLY DAY USE WHERE THERE IS NO GRID CONNECTIVITY AND NO DG.

Yes, you can. Although, it wont be safe to run few applications as electricity might vary. You can use a correct controller.

2- CAN WE DESIGN A SOLAR SYSTEM WITH MINIMUM BATTERY BANK, SO THAT WE MAY USE AS WELL CHARGE BATTERIES TOGETHER IN DAY TIME, AND KEEP BATTERIES FOR MINIMUM LOAD AT NIGHT.

Technically, yes, you can.

3- IS THERE ANY LIMITATION AS FAR AS VOLTAGE AND CURRENT IS CONCORN ON HOW MANY PANELS CAN BE CONNECTED IN SERIES OR PARALLEL

Limitation depends on your usage. You can add arrays as required.