AS 5715:2015 – Uninterruptible power systems (UPS) forroadside devices.
The UPS controller consists of a number of functional elements:
(a) Rectifier.
(b) l3attery management system.
(C) Inserlcr.
(d) Switching mechanism,
(e) Interfaces.
The UPS controller shall be adequately rated for the intended load specified
NOTE: The ,ntcndcd load should bc specified by the purchascr
The rectifier of the UPS shall convert the input a.c. supply to a regulated dc. output for use by the UPS battery charger (sec Clause 4.3) for charging the UPS storage batteries. For UPS of the double-consersion type, this output shall also supply the UPS inserter (see Clause 4.4),
4.3.1 General
The battery managenwnt system shall comprise a battery charger, sensors and control circuitry.
Under the full range of Input supply voltages and environmental factors, and the full range of load conditions, including overloads, the battery management system shall do the following:
(a) Provide optimum charging and appropriately staged charge management of the type of storage batteries and capacities required for the UPS.
(b) Provide capacity to charge the storage batteries at their maximum rate of charge.
(c) Maintain the storage batteries in optimal state of charge for all conditions and circumstances of operation and prevent overvoltage being applied to the storage batteries.
(d) Recharge, including trickle charge when appropriate, the storage batteries under temperature compensation controlled conditions with feedback provided by a skin temperature sensor on a typical storage battery.
(e) Prevent the generation of undesirable harmonic currents in the supply authority’s circuits due to the charging operation.
(f) Limit ripple voltage on the d.c. rail of the storage batteries to less than 0,25% of the battery bus voltage.
(g) Prevent damage to the battery charger and its power semiconductor components by providing automatic output current limiting fir all forms of output current overload. 1 he output current limiting l’unction shall not cause the operation of supply protective devices for the power semiconductor components. Upon removal of the overload condition, the battery charger shall automatically return to normal operation.
(h) Provide appropriate indication within the UPS status indicators when an overload condition occurs to the baucry charger.
(i) Provide a power factor of not less than 0,95 when the UPS is charging the storage batteries and the load is disconnected.
(j) Provide the required data to and accept commands from the user interface.
When the UPS is supplied by a portable generator with appropriate output ratings, the battery management system shall operate with the came performance as when the UPS is connected to normal mains power supplies.
4.3.2 Battery cell balancln
Where specified by the battery manufacturer, cell balancing shall be provided by the battery management system.
The inverter of the UPS shall do the following:
(a) Maintain the specified UPS output voltage to the specified tolerances over the full variation of the storage battery voltage,
(b) Shut down in the event that the output voltage cannot he maintained within the required parameters specified in Table 7.1.
(c) Shut down in the event that the inverter’s input d.c. voltage decreases below the minimum allowable.
(d) Synchronize the UPS output voltage and phase with the input ac. source to within tO V and 2°. For the purpose of this requirement, the UPS output frequency’ slew rate shall be lintited to I cycle per second maximum during the synchroniiation process.
(e) Prevent damage to the inserter and its power semiconductor components by providing automatic output current limiting for all forms of UPS output current overload. The output current limiting function shall not cause the operation of power supply protective devices.
4.5.1 Function
The switching mechanism shall provide for automatic switching of the load between the primary power and secondary power tUPS output).
NOT[- rhis operates differently for the different LI’S configurations,
4.5.2 Stand-b and line-Interactive configurations
For stand-by configuration, the switching mechanism shall connect the load to the primary power in normal mode. In the event of primary power failure, as defined in Clause 7.2.