BMS stands for Battery Management System. It is an electronic system that manages a rechargeable battery. https://en.wikipedia.org/wiki/Battery_management_systemA BMS is typically required to control the batteries installed in series in a battery bank. This is required for Lead Acid batteries, Lithium batteries of all types and generally, the battery bank made of several cells in a series requires the BMS, As the cells installed in series or parallel in a battery bank need to have similar voltages when charged and discharged if the cell voltage varies beyond a certain limit than the one or two cells get over charged or under charged which creates an imbalance in the battery bank. If these cells are not balanced in time, then these cells will make the battery unusable. And its main advantages are:

• Monitor the battery’s state of charge (SOC), voltage, current, temperature, and other parameters.
• Protect the battery from operating outside its safe operating area.
• Balance the cells in the battery pack to ensure they all have the same voltage.
• Optimize the battery’s performance.
• If that feature is activated, report the battery’s status to an external device.
• The BMS is required for most battery types if the cells are in series in a battery bank.

Lithium battery bank

There are two main types of BMSs: centralized and distributed. A centralized BMS uses one control unit to manage all of the battery cells in the system. A distributed BMS uses multiple control units to manage the battery cells in the system.

BMSs are used in a variety of applications, including:

• Electric vehicles
• Hybrid electric vehicles
• Solar power systems
• Uninterruptible power supplies (UPSs)/Inverters
• Portable devices
• Industrial machinery

BMSs ensure rechargeable batteries’ safety, reliability, and performance.

Here are some of the benefits of using a BMS:

• Improved battery safety: A BMS can prevent the battery from overcharging, over-discharging, overheating, and other conditions that can damage the battery.
• Extended battery life: A BMS can help extend the battery’s lifespan by preventing it from operating outside its safe area.
• Improved battery performance: A BMS can optimize the battery’s performance by balancing the cells and managing the battery’s temperature.https://suvastika.com/battery-management-system-bms-for-lead-acid-battery/
• Reduced maintenance costs: A BMS can help to reduce maintenance costs by preventing battery failures.
• Increased uptime: A BMS can help increase uptime by preventing battery failures and ensuring that the battery always operates optimally.

 

 

The sizing of the Solar charge controller according to the battery sizing is very important to understand so that we don’t design a system that can be harmful to the batteries or can explode, especially Lead Acid batteries. A solar charge controller is a device that regulates the flow of electricity from solar panels to batteries.https://www.sciencedirect.com/topics/engineering/charge-controller It prevents the batteries from being overcharged or undercharged, which can damage them. Solar charge controllers are sized based on the following factors:

• Solar array output: The solar array output is the total power the solar panels can produce. This is typically measured in watts.
• Battery bank voltage: The battery bank voltage is the voltage of the batteries the solar charge controller will use. This is typically 12, 24, or 48 volts or a multiple of 12 Volts in the case of lead Acid batteries.https://suvastika.com/how-to-match-the-solar-panel-voltages-and-battery-voltage-in-solar-hybrid-pcu/
• Battery bank capacity: The battery bank capacity is the amount of energy the batteries can store. This is typically measured in amp-hours. So, generally speaking, the Tubular lead Acid battery needs to be charged by 10% of its rated capacity. So, for example, if we use a 150 Ah Tubular battery, we can give 15 Amps of charging to charge the tubular battery. So if we are installing a single 150 Ah Tubular battery in a Solar System, we should ensure that we don’t charge this battery beyond 20 Amps charging current; otherwise, the Tubular battery may be bulged initially and might explode if we try to charge with 40 or 50 Amps charging current.

Solar System with battery and Solar Panels

For example, if you have a solar array with 1000 watts of output and a 24-volt battery bank, you will need a solar charge controller with a minimum amperage rating of 1000 / 24. It will be 41 Amps charging current; theoretically, we get it from the solar panels. So if there is a tubular battery, the charge controller will Charge the battery depending upon the PWM or MPPT charge controller. The PWM will give approximately 30 Amps of charging from the 1000 Watt Solar panels, and MPPT will give approximately 38 to 39 Amp Charging current as the 100% of the Solar panels’ output is impossible to get. There will be a loss in wires, and the maximum solar peak power will be for 3 to 4 hours. As cleaning the solar panels in most areas is impossible, a loss will also be added to that account. The Tubular lead Acid batteries need to be charged in 10 hours, but what will be the result if we charge them faster? As we see in most of the recent installations done in India and Africa and other such countries where the Solar PCU IS USED TO INSTALL HYBRID SOLAR OFF-GRID SYSTEMS, THE MANUFACTURER is giving HIGH AMPERE CHARGE CONTROLLERS IN SIDE THE PCU to give the option of installing higher capacity of Solar panels to destroy the battery life. Battery explosion incidents are happening in Tubular Lead Acid batteries. Then a few of the manufacturers are trying to convince that their PCU does the Load Sharing when the grid is available so that the solar will share the Load between the battery and Load, which is a false propaganda by the manufacturers. No one is checking that in the Solar PCU, the power from the solar panels can only charge the battery and can’t run the Load when the grid power is available. In most if the Solar PCUs available in the market the solar panel charges the Tubular battery to 100% And than the PCU switches on the Inverter mode and start giving power to tge load even when the Grid is available and that time load is shared between solar panel and battery. So one should consider the Charge controller and solar panels rating before installing the panels. Having more panels with a smaller battery will create more problems for the user as the water topping will be more required. Battery life will be reduced, and if the panel size is too big for the battery to handle, then the chances of battery explosion cant be avoided in the Solar PCU system.

Lithium Battery option for bigger charge controller designing: the Lithium battery can be charged at 50% of its capacity, so with a Lithium battery, one can use a bigger charge controller and can install a higher solar panel size bank.https://suvastika.com/lithium-battery-option-in-inverter-ups-solar-pcu/#:~:text=We%20at%20Su-vastika%20have%20provided%20our%20inverter%2FUPS%2FSolar%20hybrid,only%20connect%20Tubular%20SMF%20and%20lead%20Acid%20batteries.

Here are some additional tips for sizing a solar charge controller:

• You may need to size your solar charge controller for a higher amperage rating if you have a bigger battery bank sizing or installing a Lithium battery bank.
• If you plan on using your solar system to power high-wattage appliances, you may need to size your solar charge controller according to battery bank sizing and than use higher battery bank voltage like 48V or 96 or 180volt battery bank sizing so that the current is reduced through the solar panels.
• If you are unsure how to size a solar charge controller, it is always best to consult a solar installer. They can help you choose the right solar charge controller for your needs.

 

Maximum PowerPoint Tracking, frequently referred to as MPPT is an electronic system that operates the Photovoltaic (PV) modules in a manner that allows the modules to produce all the power they are capable of. MPPT is not a mechanical tracking system that physically moves the modules to make them point more directly at the sun. MPPT is a fully electronic system that varies the electrical operating point of the modules to deliver maximum available power.https://en.wikipedia.org/wiki/Maximum_power_point_tracking

solar panel graph

MPPT charge controllers offer several benefits over PWM charge controllers, including:

• Increased charging efficiency: MPPT controllers can increase the charging efficiency of a solar system by up to 30%. This is because they track the solar panel’s maximum power point (MPP) and adjust the voltage and current accordingly. In low-light or cold conditions, where the solar panels produce more voltage than the battery bank can handle, MPPT controllers can still extract the maximum power from the panels.
• Flexible design enables the user to use panel and battery rating as required.
• Smart MPPT tracking algorithm to provide a current boost of up to 30%
•  
• Faster charging of the batteries compared to the PWM Charge controller
• Temperature-compensated Battery charging to protect the battery
• Auto/Manual Periodic Equalization charging for reducing the lead Acid battery sulfation and enhancing life.
• Increased power output: MPPT controllers can also increase the power output of a solar system by up to 30%. This is because they can track the MPP of the solar panels and adjust the voltage and current to match the changing conditions of the solar irradiance and temperature.
• Reduced wire size and length: MPPT controllers can operate at higher voltages and lower currents than PWM controllers. This can reduce the wire size and length between the solar panels and the battery bank, saving money and installation time.
• Compatibility with more solar panels: MPPT controllers are compatible with a wider range of solar panels than PWM controllers. This is because they can track the MPP of solar panels with different voltage and current characteristics.
• More features: MPPT controllers often have more features than PWM controllers, such as temperature compensation, load control, and battery type selection. These features can make MPPT controllers more versatile and user-friendly.https://suvastika.com/maximize-battery-life-in-ups-inverter-by-having-atc-feature-for-charging-lead-acid-batteries/#:~:text=ATC%20monitors%20the%20battery%E2%80%99s%20temperature%20and%20adjusts%20the,the%20battery%20from%20overheating%2C%20leading%20to%20premature%20degradation.

• Lithium battery compatibility: The new MPPT-based charge controllers are compatible with Lithium battery charging through solar panels.https://suvastika.com/lithium-battery-option-in-inverter-ups-solar-pcu/#:~:text=We%20at%20Su-vastika%20have%20provided%20our%20inverter%2FUPS%2FSolar%20hybrid,only%20connect%20Tubular%20SMF%20and%20lead%20Acid%20batteries.

Overall, MPPT charge controllers offer several benefits over PWM charge controllers. If you are looking for the most efficient and powerful way to charge your solar batteries, an MPPT controller is the best option.

Here are some additional considerations when deciding whether to use an MPPT charge controller:

• The size of your solar system: MPPT controllers are typically more expensive than PWM controllers. However, the cost difference may be offset by the increased efficiency and power output of an MPPT controller. If you have a large solar system, then the cost of an MPPT controller may be worth it.
• The climate you live in: If you live in a cold climate, then an MPPT controller is a good option. MPPT controllers can extract more power from solar panels in cold conditions.

POWER SECTION: The power Section consists of a Buck converter, a DC-DC Converter used to Step down the Panel Voltage to charge the battery with the maximum current. Because the duty cycle of the buck converter Will be decided according to the Vmp and Imp Of the solar panel.https://suvastika.com/difference-between-mppt-and-pwm-solar-charge-controller/

MPPT Solar Charge Controller has the Four Stage Battery Charging Process (Bulk, Absorption, Float, Equalization)

MPPT charge controller has this Protection Against

Reverse Battery Connection

Surge Protection

Ambient Temperature Compensation

Heat Sink Temperature Compensation

Reverse Battery Current Flow Protection

PV High Current Protection

Overload and Short Circuit Protection

Conclusion: MPPT Solar Charge Controller increases the efficiency of solar panels.

 

The main difference between PWM and MPPT charge controllers is how they track a solar panel’s maximum power point (MPP).

• PWM (Pulse Width Modulation) charge controllers use a simple method of charging a battery by switching the current on and off at a very high frequency. This method is relatively inexpensive and easy to implement but less efficient than MPPT controllers. PWM controllers also have a lower voltage range than MPPT controllers, which can limit their use in some applications.
• MPPT (Maximum Power Point Tracking) charge controllers use a more advanced method of tracking the MPP of a solar panel. This method involves constantly adjusting the voltage and current output of the controller to ensure that the panel is always operating at its maximum power point. MPPT controllers are more efficient than PWM controllers and can be used with a wider range of solar panels.
• Maximum Power Point Tracking, frequently referred to as MPPT is an electronic system that operates the Photovoltaic (PV) modules in a manner that allows the modules to produce all the power they are capable of. MPPT is not a mechanical tracking system that physically moves the modules to make them point more directly at the sun. MPPT is a fully electronic system that varies the electrical operating point of the modules to deliver maximum available power.

solar panel graph

MPPT charge controllers are generally the better choice for most solar applications. They are more efficient, can be used with a wider range of solar panels, and can provide a longer lifespan for your battery. However, MPPT controllers are also more expensive than PWM controllers.https://suvastika.com/whats-pwm-solar-charge-controller/

There are important features which should be there in the MPPT charge controller to give a better performance, like Four Stage Battery Charging Processes (Bulk, Absorption, Float, Equalization) and ATC (Automatic Temperature compensation) for the temperature change to be compensated while charging through the Solar panels.

 Also, these Protection Against

Reverse Battery Connection

Surge Protection

Ambient Temperature Compensation

Heat Sink Temperature Compensation

Reverse Battery Current Flow Protection

PV High Current Protection

Overload and Short Circuit Protection

Here are some factors to consider when choosing between a PWM and MPPT charge controller:

• The size of your solar system: A PWM charge controller may be sufficient if you have a small solar system. However, an MPPT charge controller will be more efficient if you have a larger solar system, and the cost of Solar panels Vs an MPPT charge controller can be compared. There will be great savings in cost as the bigger the system higher the savings in cost if we use MPPT solar charge controller compare to the PWM solar charge controller.
• The type of solar panels you have: If solar panels have a high maximum power voltage (Vmp), an MPPT charge controller can extract power from your panels.
• Your budget: PWM charge controllers are less expensive than MPPT charge controllers. However, the extra cost of an MPPT charge controller may be worth it if you have a large solar system or want to maximise your solar panels’ power output.https://en.wikipedia.org/wiki/Charge_controller

 

An off-grid solar PV system is a solar power system that is not connected to the electrical grid. This means that the system must generate all the electricity needed to power its appliances and lights, even at night or when there is no sunlight.

Off-grid solar systems are typically used in remote areas without access to the electrical grid, such as rural areas or islands. They can also be used by people who want to be more self-sufficient and reduce their reliance on the grid.https://en.wikipedia.org/wiki/Off-the-grid

solar panels picture

Off-grid solar systems typically consist of the following components:

• Solar panels: The solar panels give DC power.
• Inverter: The inverter converts the DC electricity from the solar panels into AC electricity that can power their load.
• Batteries: The batteries store excess electricity generated by the solar panels for use at night or when there is no sunlight.
• Charge controller: The charge controller regulates the flow of electricity from the solar panels to the batteries to prevent them from being overcharged; it also keeps the battery properly charged and controls the LCV cutoff for battery safety.https://suvastika.com/whats-pwm-solar-charge-controller/

The cost of an off-grid solar system will vary depending on the size of the system, the type of solar panels and inverter used, the solar charger controller type used for powering the Solar PV System and the cost of labour.

Here are some of the advantages of using an off-grid solar system:

• Independence from the grid: You generate your power through this Solar PV system, which is very stable but dependent on the batteries and the bank’s sizes.
• Reduced reliance on fossil fuels: You’ll reduce your carbon footprint by generating electricity from solar PV power.
• Lower energy costs: Over the long term, using an off-grid solar system is used where there is no power, so bringing the electricity from far-flung areas costs much money and maintenance. This is the cheapest power which can be installed anywhere without bringing diesel or petrol if running a diesel or petrol generator.
• Carbon Emission is reduced: adopting this system reduces carbon emissions and can get carbon credits if this is a large system.
• Lithium battery adoption: Now, the off-grid system installed with Lithium batteries has become more reliable, and the running and maintenance cost has been reduced as the Lithium battery life is four times the life of any Lead Acid battery type, whether Tubular or Gel battery. As the Lithium battery is cheaper than the Tubular Lead Acid battery.

Here are some of the disadvantages of using an off-grid solar system:

• High upfront cost: Off-grid solar systems can be expensive compared to the initial cost of a Generator, but in the long run, it will be cheaper than a Generator as the fuel cost will be compensated.
• Solar panel maintenance: Solar panels must be cleaned regularly to keep them producing at peak efficiency. Which is the cost one must consider depending on the location.
• Battery maintenance: Batteries need to be replaced periodically, which can be costly. Nowadays, Lithium battery has been a big success in Solar Off-grid system. It is a cost-effective solution as the panels have 25 years of life, and Lead Acid battery life is limited by 2 to 3 years which can go up to 10 years if Lithium is used in place of Lead Acid batteries.
• Nighttime and cloudy weather performance: Off-grid solar systems won’t produce any electricity at night or when it’s cloudy. You’ll need a backup generator or a larger battery bank to power your appliances during these times.

Considering an off-grid solar system, it’s important to weigh the pros and cons carefully to decide if it’s the right choice for you.

 

What is Solar PV System? A solar PV system is a system of solar panels, inverters, batteries, and other equipment that converts sunlight into electricity for use in a home, office, factory or any other building. Solar systems can generate electricity for all or part of the home, office, factory or building etc., energy needs, depending on the system’s size and the energy needs.https://en.wikipedia.org/wiki/Photovoltaic_system

Solar panels are the most important component of a solar system. They comprise photovoltaic cells that convert sunlight into direct current (DC) electricity. AN INVERTER CONVERTS the DC electricity from the solar panels into alternating current (AC) electricity. The AC electricity can then be used to power homes, offices, factories etc., to run appliances, machinery and other loads. 

How many types of Solar PV type of  Systems are there in the world

• Grid Tie or Grid Feed Solar System
• Off-Grid Solar System
• Hybrid Off-Grid Solar System
• DC Solar System
• Hybrid On-Grid and Off-grid Solar System

–    Grid-tied Solar Systems generate electricity for your home or business and route the excess power into the electric utility grid for compensation from the utility company having the solar panels and Grid-tied Inverter.

• Off-Grid Solar PV System Places where the utility power is unavailable, the Solar System needs an independent system comprising Solar panels, inverters and batteries to store the solar power and use it during the day and at night through the storage system.

• Hybrid Off-Grid Solar PV System: In this system, there is utility power available and the solar power is stored in the battery through the Grid power as well through the solar power and the grid power is bypassed when the power is available, and the solar power is utilized to run the power when the battery is completely charged or when the grid power fails then the stored power in the battery is utilized. This Solar system is called Hybrid Solar PCU as well. Hybrid Solar Power Conditioner.https://suvastika.com/solar-pcu-the-future-of-home-power-with-bluetooth-and-wi-fi-mobile-application/

• Hybrid Solar On-Grid and Off-Grid PV Solar System: This system has a battery of solar panels and Hybrid Solar inverters with off-grid and Grid Tied features. The Grid power is available, and the user can utilize the solar power saved in the battery in case of power failure or at night when solar power is not available to power the home office.

 Hybrid On-Grid and OFF-Grid Solar PV System: This is the system which combines the On-grid and off-grid features where Solar PV power generated can be fed into the Grid and can be stored in the battery as well to provide power when solar PV power is not available or when there is a power cut in the Grid than the stored power in the battery can be used.

 Solar PV-based Solar DC System: In a Solar DC system there is DC power coming from the solar panels can be used as Dc power through the charge controller directly stored in the DC battery, which is the most efficient of Solar power usage as there is no conversion of DC to Ac power and Dc coming from the Solar PV system is directly stored into the battery and then can be used to run DC powered equipment like DC fans, LEDs, DC fridge, DC air conditioners etc.https://en.wikipedia.org/wiki/DC Solar

Solar PV DC systems will provide direct charging to Electric vehicles as this will be the cheapest power available in the world.

Solar System with battery and Solar Panels

Solar systems offer several advantages, including:

• Reduced electricity bills: Solar systems can help to reduce electricity bills by generating electricity on-site. This can save owners money on their monthly utility bills.
• Where no power is available, it can generate power independently at the cheapest cost.
• Environmental benefits: Solar PV systems produce no emissions, so they can help to reduce a  carbon footprint.
• DC Solar PV Systems are the future technology which is gaining attraction in areas where the power cannot reach even today.
• EV technology will have to charge the vehicles through the Solar PV system only in the future; otherwise, another fossil fuel crisis will occur.
• Government incentives: Many government incentives, such as tax credits and rebates, are available for people in different locations and geographies of the world who install solar PV  systems.

 

Here are the steps to charge a Tubular lead Acid Deep Cycle battery in Inverter/UPS.https://en.wikipedia.org/wiki/Deep-cycle_battery

1. Make sure the battery is in a well-ventilated area.
2. Disconnect the battery from any load.
3. Connect the tubular Deep Cycle lead acid battery to the inverter/UPS to the battery terminals.
4. Please check the inverter/UPS settings for tubular battery settings at the back of the Inverter/UPS selection switch. The recommended voltage for a tubular deep-cycle battery is 14.4 volts. The current setting should be no more than 10% of the battery’s capacity. For example, a 100Ah battery should be charged with a current of no more than ten amps. And 150 Ah Tubular battery should not be charged more than 15 Amps Charging Current.
5. Turn on the Inverter/UPS and allow it to charge the battery for 24 hours for the first charging, which is very important when the first time Inverter/UPS is installed.
6. After 24 hours, check the battery voltage. After 24 hours of charging, it should reach 13.5 to 13.6 Volts.
7. The Inverter/UPS should have four stages of minimum charging, described as the Bulk stage, Absorption stage, Float mode and Trickle charging stage, to maintain the battery life and proper backup time for a Tubular Lead Acid battery.https://suvastika.com/what-is-charging-rate-of-a-battery/
8. Once the battery is properly charged, then connect the Load to the Inverter/UPS.
9. Low Battery Cutoff Feature to protect the battery from Deep Discharge is an important parameter to check in Inverter/UPS.https://suvastika.com/prevent-tubular-battery-failure-use-low-voltage-battery-cutoff/

Here are some tips for charging a tubular battery:

• Use at least a high-quality battery Inverter/UPS designed for tubular battery 4 stage Charging.
• Do not use a locally made Inverter/UPS, which can overcharge or undercharge the Tubular deep cycle lead Acid battery. Overcharging can damage the battery and shorten its lifespan.
• Check the battery water level regularly and add distilled water as needed.
• Store the Lithium deep cycle lead acid battery in a cool, dry place.

Here are some signs that a tubular battery is fully charged:

• The battery voltage will be at least 13.6 volts after completing the Float charge.
• The battery will not accept more current from the inverter/UPS charger.
• The battery will be warm to the touch.

If you are unsure if a tubular battery is fully charged, it is always best to err on caution and continue charging it for a few more hours. Overcharging a battery is much worse than undercharging it.

 

Square Wave Vs Sinewave UPS for Computers? Most of the UPS, sold for single computer applications, come in the range of Rs 2000/ in India and are square wave UPS, all imported from China, and people buy when they buy a computer to provide backup and protection. They do not realize they are buying a square wave UPS that will damage the Computer over time rather than give it protection.

A small UPS for computer protection in square waves can harm computers. Square wave inverters produce a sharp, rectangular voltage waveform that can cause problems for sensitive electronic equipment. https://suvastika.com/why-a-pure-sine-wave-technology-is-a-must-for-your-inverter/ This is because the square wave waveform can contain harmonics, which are high-frequency components that can interfere with the operation of the Computer’s power supply. In some cases, the harmonics can cause the Computer to overheat or damage the components.

For this reason, using a square wave UPS to power a computer is not recommended. If you need to use a UPS to protect your Computer from power outages, choosing one that produces a pure sine wave output is important. Pure sine wave UPS are more expensive than square wave UPS but safer for computers. https://www.daytradingbias.com/sine-wave-and-square-wave-uninterruptable-power-supply-ups/

Here are some of the problems that can occur if you use a square wave UPS to power your Computer:

• Overheating: The harmonics in the square wave waveform can cause the Computer’s power supply to overheat. This can lead to premature failure of the power supply or other components. Rather than protecting the Computer, it ensures the Square wave UPS damages the power supply or motherboard of the Computer, which become non-repairable.
• Damage to components: The square wave waveform harmonics can also damage the Computer’s power supply components. This can lead to intermittent problems or even permanent damage to the Computer.
• Noise: The square wave waveform can also produce noise that can interfere with the operation of the Computer. This noise can manifest as audio interference, video interference, or data corruption. If you connect the computer speakers, you will get the noise once the UPS comes on the battery mode.
• Switching time is higher in the square wave UPS, so sometimes computers will reboot when the power goes or come back, which is also one reason to avoid square wave UPS.
• Built-in Stabilizer made by relays which work for stabilizing the voltage also create harmonics when the UPS is working on the Mains power as the AVR section try to correct the voltage through the switching of relays which in turn produce sparks and spikes in the UPS system which goes directly to the computer.

If you are concerned about the safety of your Computer, it is best to use a UPS that produces a pure sine wave output. Pure sine wave UPSs are more expensive than square wave UPS, but they are the only insurance for the Computer; otherwise, it’s better not to attach any UPS for the safety of the Computer as the Square wave only creates problems for the computers. Square Wave Vs Sinewave UPS for Computers is a subject which needs to be understood by everyone buying UPS to protect their Computer.