Uninterruptible power supply control in distributed power architecture

Abstract

Aspects of the disclosure relate generally to uninterruptible power supply (“UPS”) units for systems requiring back up power. The UPS units include driving circuitry for controlling charging and allowing discharging of a battery. The driving circuitry includes a controller as well as a pair of switches. The MOSFETs includes a charging and a discharging MOSFET in series with the battery operating as a bidirectional switch. When the UPS unit is connected to an AC power supply, the controller regulates the current through the charging MOSFET switch based on feedback from a feedback device in order to charge the battery. If AC power is lost, the controller goes into saturation, switching the discharging MOSFET to a on condition and allowing the battery to discharge. The transitions from AC to battery power and vice versa are automatically achieved via the controller.

1 . An uninterruptible power supply unit comprising:
 a first MOSFET switch and a second MOSFET switch;   a controller for controlling current through the first and second MOSFET switches, the controller being configured to cause the first MOSFET switch to operate in a linear region during charging;   a battery in series with the first and second MOSFET switches, the first MOSFET switch configured to charge the battery when operating in the linear region; and   a protection block in communication with the first and second MOSFET switches, the protection block configured to switch the first and second MOSFET switches off when the battery is operating out of a predetermined range of operating conditions.   
     
     
         2 . The uninterruptible power supply unit of  claim 1 , further comprising a feedback device arranged in series with the first MOSFET switch, the feedback device being configured to provide feedback information to the controller, wherein the controller is further configured to control the current through the first MOSFET switch based on the feedback current. 
     
     
         3 . The uninterruptible power supply unit of  claim 2 , wherein the feedback device includes a shunt resistor. 
     
     
         4 . The uninterruptible power supply unit of  claim 2 , wherein the controller is configured to adjust a gate-to-source voltage of the first MOSFET based on the feedback information. 
     
     
         5 . The uninterruptible power supply unit of  claim 2 , wherein the controller is configured to switch the first MOSFET on by generating a voltage through a gate of the first MOSFET based on the feedback information. 
     
     
         6 . The uninterruptible power supply unit of  claim 1 , wherein the controller comprises an amplifier. 
     
     
         7 . The uninterruptible power supply unit of  claim 1 , wherein when the charging current falls below a threshold value, the second MOSFET switch is switched on such that the second MOSFET operates in a switching region, and the second MOSFET switch is configured to provide discharging current to the battery. 
     
     
         8 . The uninterruptible power supply unit of  claim 7 , further comprising a second protection block configured to receive the feedback information from the feedback device and to switch the second MOSFET off when the battery is charging. 
     
     
         9 . The uninterruptible power supply unit of  claim 7 , further comprising a second protection block configured to receive the feedback information from the feedback device and switch the second MOSFET switch on when the battery is discharging. 
     
     
         10 . The uninterruptible power supply unit of  claim 1 , wherein the protection block comprises a processor configured to switch the first and second MOSFET switches off based on an abnormal voltage of the battery. 
     
     
         11 . The uninterruptible power supply unit of  claim 1 , wherein the protection block comprises a processor configured switches the first and second MOSFET switches off based on an abnormal current of the battery. 
     
     
         12 . The uninterruptible power supply unit of  claim 1 , wherein the protection block comprises a processor configured to switch the first and second MOSFET switches off based on an abnormal temperature of the battery. 
     
     
         13 . The uninterruptible power supply of  claim 1 , wherein the first and second MOSFET switches are configured to operate as a bidirectional switch. 
     
     
         14 . The uninterruptible power supply of  claim 1 , wherein the controller is configured to adjust a gate-to-source voltage of the first MOSFET switch when the first MOSFET switch is operating in the linear region during charging. 
     
     
         15 . The uninterruptible power supply of  claim 1 , wherein the controller is configured to automatically transition the uninterruptible power supply unit from a charging mode where the battery is charged to a back up mode where the battery supplies power to a load external to the uninterruptible power supply unit. 
     
     
         16 . The uninterruptible power supply of  claim 1 , wherein the controller is configured to automatically transition the uninterruptible power supply unit from a back up mode where the battery supplies power to a load external to the uninterruptible power supply unit to a charging mode where the battery is charged. 
     
     
         17 . The uninterruptible power supply of  claim 1 , wherein when the charging current falls below a threshold value, the first MOSFET switch is switched to on such that the first MOSFET operates in a switching region, and the first MOSFET switch is configured to provide discharging current from the battery. 
     
     
         18 . A backup power supply comprising:
 a first uninterruptible power supply unit, the first uninterruptible power supply unit comprising:
 a first MOSFET switch and a second MOSFET switch; 
 a controller for controlling current through the first and second MOSFET switches, and wherein the controller being configured to cause the first MOSFET switch to operate in a linear region during charging; 
 a first battery in series with the first and second MOSFET switches, the first MOSFET switch is configured to charge the first battery when operating in the linear region; and 
 a protection block in communication with the first and second MOSFET switches, the protection block being configured to switch the first and second MOSFET switches off when the first battery is operating out of a predetermined range of operating conditions; and 
   a second uninterruptible power supply unit comprising a second battery;   wherein the first uninterruptible power supply unit is configured to control the charging current, charge the first battery, and switch the first and second MOSFETs independently of the second uninterruptible power supply unit.   
     
     
         19 . The backup power supply of  claim 17 , wherein when the charging current falls below a threshold value, the first MOSFET switch is switched to on such that the first MOSFET operates in a switching region, and the first MOSFET switch is configured to provide discharging current from the battery. 
     
     
         20 . A system comprising:
 a load configured to receive power from a power supply;   an uninterruptible power supply unit in communication with the load, the uninterruptible power supply unit comprising:
 a first MOSFET switch and a second MOSFET switch; 
 a controller for controlling current through the first and second MOSFET switches, and wherein the controller being configured to cause the first MOSFET switch to operate in a linear region during charging; 
 a first battery in series with the first and second MOSFET switches, the first MOSFET switch is configured to charge the first battery when operating in the linear region; and 
 a protection block in communication with the first and second MOSFET switches, the protection block being configured to switch the first and second MOSFET switches off when the first battery is operating out of a predetermined range of operating conditions; 
   wherein when the charging current falls below a threshold value, the first MOSFET switch is switched on such that the first MOSFET operates in a switching region, and the first MOSFET switch is configured to provide discharging current from the battery to the load.   
     
     
         21 . The system of  claim 19 :
 wherein the uninterruptible power supply unit further comprises a feedback device arranged in series with the first MOSFET switch, the feedback device being configured to provide feedback information to the controller, and   wherein the controller is further configured to control the current through the first MOSFET switch based on the feedback current.