What is the principle of float charging of UPS batteries?
A UPS (uninterruptible power supply) system is a device used to provide stable, uninterrupted power supply. It is widely used in various places that require continuous power supply, such as data centers, medical facilities and communication infrastructure. In order to ensure that sufficient power is provided during power grid outages or power fluctuations, UPS battery float charging plays a vital role.
UPS battery float charging means that when the battery is fully charged, the charger continues to charge the UPS battery with a constant small current to balance the natural discharge of the battery, thereby ensuring that the UPS battery can remain fully charged during a power outage. The specific principle is as follows: In the power supply system, the rectifier and the battery are connected in parallel on the feeder. When the mains power is normal, the rectifier will supply power and at the same time recharge the battery with a small current. This specific charging method is designed to keep the battery state of charge and prevent overcharging and over-discharging. It is based on the constant voltage charging principle and has been widely adopted in practice.
During float charging, the battery continues to receive current to replenish its own energy, and the voltage remains at a constant level. This constant voltage is usually maintained at the battery’s rated voltage to ensure battery safety while still being able to provide the required current when load demand increases.
When load demand increases, the UPS system draws energy from the battery to provide the required power. In this case, the battery’s voltage will decrease, and the charger will automatically provide additional current to replenish the battery and keep it charged in a float charging state.
The float charging has many advantages. First,the battery is continuously charged, ensuring that the UPS system is always prepared to deliver uninterrupted power supply. Additionally, float charging helps safeguard the battery by preventing overcharging and over-discharging, thereby minimizing battery degradation.
In order to achieve precise control of float charging, UPS batteries are equipped with intelligent Battery Management Systems (BMS). The primary function of the BMS is to monitor the battery voltage and replenish the battery’s energy by controlling the current through disconnection or closure when necessary. The charger continuously adjusts the output current to ensure that the battery remains in the optimal float charging state.
In addition, the BMS in the UPS battery can also provide real-time monitoring of the battery status.By continuously monitoring the battery’s voltage, current, temperature, power, SOC (state of charge), SOH (state of health), SOP (state of power) and SOE (state of energy), the BMS can determine whether the battery is functioning properly. If an abnormality is detected, such as battery aging or failure, the system can issue an alarm in time so that appropriate maintenance measures can be taken.
In short, the floating charging principle of UPS batteries is to maintain the charging state of the battery through constant voltage charging and prevent overcharging and over-discharging. This charging method plays a vital role in the UPS system, ensuring that the battery can reliably provide uninterrupted power and improve the power quality of the equipment. Through float charging, we can ensure that the UPS system is always in optimal working condition and provide reliable power guarantee for various critical applications.
As a professional UPS battery manufacturer, PLB’s developed UPS lifepo4 batteries has overcome the industry bottlenecks of lithium batteries, achieving ultra-long float charging and high-rate discharge of the battery, making UPS batteries more stable, safe and reliable.