POWER SYSTEM AND SOLAR INTEGRATION
Battery is the primary power source for any electronics wireless gadget, be it a smartphone, laptop, watch or remote.
Cell: A cell is an energy source which can deliver only DC voltage and current which are in very small quantities
Example : Remote cell,watch cells ,these batteries will only produce 1.5v-3v
Battery: The functionality of the battery is exactly same as that of a cell but a battery is a pack of cells arranged is a series/parallel fashion so that the voltage can be raised to desired levels.
Examples :Power banks which is used to charge Smartphone.
AC cannot be stored but we can store the dc , losses are more for AC when compare to DC , so therefore in portable electronic gadgets we will use for DC
Technical terms
Only using current and voltage we can’t explain functionality of battery, Watt-hour (mAh), C-rating, nominal voltage, charging voltage, charging current, discharging current, cut off voltage, shelf life, cycle life are the few terms used to define a batteries performance.
1. Power capacity :Energy stored in battery which is measured in Watt-hour
Watt –hour =V*I*hrs (Volatge will be constant )=Ah/mAh
2. Power capability :Amount of current battery can deliver .(C-rating)
3. Nominal voltage :when we are defining a power capacity of battery we will take battery voltage as constant , that constant volage is Nominal voltage
4. Charging current :Maximum current that can be applied to charge a battery 500mA is best range of charging current ,Now we can charge from 1A/2A current also
5. Charging voltage : Maximum voltage that be applied to charge a battery .Basically 4.2v is the standard voltage to charge a battery .so if we apply 5v also it will take 4.2v
6. Discharging current :Current drawn from battery and its deliver to the load.If the current drawn from the load is greater than the rated discharging current then battery will drain fast ,so it will cause to explode the battery and heat-up the battery fast .
7. Shelf life: Time period of battery can be stay powered up and should be able to use it for a rated time period .shelf life is considered for only non rechargeable batteries
8. Cut-off voltage : voltage at which the battery can be fully discharged .Beyond the cu-off voltage the battery should disconnect from load .
9. Cycle life : Let’s consider a battery is fully charged and it is discharged to 80% of its actual capacity, then the battery is said to be completed one cycle. the number of such cycles that a battery can charge and discharge defines the cycle life. The more the cycle life the better will be the battery’s quality.
10. Power density : It defines power capacity of battery for a given mass of volume.
What will change when Batteries are connected series or in parallel
In a series connection, batteries of like voltage and amp-hour capacity are connected to increase the voltage of the overall assembly.
In a parallel connection, batteries of like voltages and capacities are connected to increase the capacity of the overall assembly.
Types of Batteries
a. Primary batteries
b. Secondary batteries
a. Primary batteries :Primary batteries are non-rechargeable batteries ,these batteries we can yse only one time, these cannot be recharge and use again.
Types :Alkaline batteries and coin cell batteries
Comparison between the Alkaline batteries and Coin cell batteries
b.Secondary batteries :Which can be recharge and reuse the battery again Though the cost is high, but they can be recharged and reused and can have a huge life span when properly used and safely charged
Types :Lead-acid Battery ,Lithium ion ,Ni-cd batteries,Ni-MH battery,Li-PO battery.
Comparison between the different types of secondary battery
Charge Controller
A charge controller/charge regulator/Battery regulator limits the rate at which electric current added or drawn from electric batteries.
It prevents overcharging and may protect against over voltage, which can reduce battery performance or lifespan and may pose a safety risk
Types of solar charge controller
A. Pulse Width Modulation (PWM) solar charge controllers
PWM controllers work by slowly reducing the amount of power going into your battery as it approaches capacity.
When your battery is full, PWM controllers maintain a state of “trickle”, which means they supply a tiny amount of power constantly to keep the battery topped off.
With a PWM controller, your solar panel system and your home battery need to have matching voltages. In larger solar panel systems designed to power your whole home, panel and battery voltage aren’t typically the same. As a result, PWM controllers are more suited for small DIY solar systems with a couple of low voltage panels and a small battery.
B.Maximum Power Point Tracking (MPPT) solar charge controllers
MPPT solar charge controllers are a more expensive and complex charge controller option. They provide the same switch-like protection that a PWM controller does, and will reduce the power flowing to your home battery as it nears capacity.
Comparison between PWM and MPPT solar charge controller
Why do we need a Charge Controller ?
Rooftop or ground-mount solar installations with a battery backup are almost always linked to the electric grid, and in the case that your battery completely fills up, your excess solar energy will automatically reroute there.
T o receive the Constant output Voltage and current from Array end to the Battery pack .Because , The current drawing from solar must be Constant then the battery will charge as featured made for that.
If the current fluctuating then battery will drain fatly as compare to life cycle and its give the output voltage /Current less itself
Why no need charge controller for USB charging to load ?
Fro USB we will get constant voltage and current from the output to battery so the battery will work fine.Usb input voltage will 230 V AC it will give 5V constant output voltage
In solar when we use Charge controller in between the solar and battery then the charge controller regulate voltage as per the charging needs.
Advanced features of charge controller : low voltage disconnect (LVD), lighting controls, adjustable settings for different battery types, auto equalization, fusing, temperature compensation and reverse polarity protection.
Voltage regulator is the main component in the charge controller.As we need to supply constant input to the load .
For the better use of battery and its life span we need to use the Charge controller when ever the input Voltage and Current is not stable.