Classifications

• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
  • H02J9/00—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting
  • H02J9/04—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source
  • H02J9/06—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over, e.g. UPS systems
  • H02J9/062—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over, e.g. UPS systems for AC powered loads

Definitions

• the present invention relates to a supply system for un ⁇ interruptible electric power, comprising a back-up power unit provided with a battery serving as a source of energy, means for charging the battery, as well as an inverter between the battery and a critical load.
• a rectifier for charg ⁇ ing the batteries and said inverter can also consist of one and the same apparatus, whose operation either as a rectifier or as an inverter depends on the state of a supply mains.
• UPS Uninterruptible Power Supply
• Fig. 1 illustrates a so-called “True-UPS” system
• fig. 1B shows a so-called “Stand-by UPS” system.
• a stand-by system can be technically resolved also in a manner that, when the mains is in proper order, power flows in an inverter from the mains to a battery. Thus, the charging of a battery proceeds through this unit and a separate rectifier is not need ⁇ ed (so-called tri-port system) .
• UPS systems have been commercially available roughly for as long as computers. Earlier, the stand-by source of power was provided by rotary converter, later and at present nearly exclusively by static, electronic converter.
• An object of the invention is to find a solution to such • a demand, i.e. to provide the above type of flexible and thus optimizable UPS system whose need of maintenance is negligible.
• a system of the invention which is .characterized in that a back-up power unit included in the system is fitted in a normal current supply system prior to its branching to a plurality of outlets and the system is provided with outletwise load decoupling switches adapted to be controlled by means of a programmable control means, included in the sys ⁇ tem and programmed for the optimum exploitation of back-up energy.
• fig. 1A shows a general block diagram for a UPS system (True-UPS) .
• Fig. 1B shows another general block diagram for a UPS system (Stand-by UPS) .
• Fig. 2 shows the disposition of components included in a UPS system of the invention in a normal current supply system.
• Fig. 3 shows a block diagram for a smart control unit SU (Smart Unit) included in a UPS system of the invention.
• Smart Unit Smart Unit
• Fig. 4 shows a block diagram for an outletwise active switch AS, connected with a UPS system of the invention and controlled by SU.
• a UPS system shown in fig. 1A includes a conventionally mains-connected rectifier/charger 1 which converts alternating current to direct current and charges a battery 2 serving as a storage of energy.
• An inverter 3 converts the direct current coming from charger 1 or battery 2 to alternating cur ⁇ rent which is supplied to a critical load 4.
• the supply of electric power during a mains failure can also be effected by means of a system shown in fig. 1B wherein, in a normal state, a load 4 is connected through a change-over switch 9 to the mains and a set of accumu ⁇ lators 2 is maintained through a lower-capacity charger 1 at its full charging capacity.
• the change-overswitch 9 transfers the supply of load from the mains through inverter 3 to batteries 2.
• the time taken by such change-over switching is a few milliseconds which is generally ac ⁇ cepted by data processing equipment making up the load.
• UPS Uninter- ruptible Power Supply
• SU Smart Unit
• AS Active Switch
• Shown with a dash-and-dot line in fig. 2 is e.g.. the path of a carrier wave-based command signal be ⁇ tween control unit 6 and decoupling switches 7 along a current supply system.
• a control unit 6 (fig. 3) can be included in the moni ⁇ toring and control unit of a UPS apparatus or it can be separate therefrom.
• a central processing unit 10 (CPU) included in control unit 6 is provided with a memory and a keyboard for manual data feeding.
• the central processing unit 10 (CPU) is adapted to receive fed-in information about battery voltage (U, , ) , battery loading (I , ) and the state of supply system (line ON/OFF) .
• the central pro ⁇ cessing unit controls decoupling switches 7, mounted at the outlets and equipped with an address.
• a code generator 11 included in control unit 6 develops an address code characteristic of each decoupling switch 7 according to which decoupling switch 7 a control command is intended for.
• a decoupl ⁇ ing switch 7 of fig. 4 includes a code analyzing block 12 in which an address code is set.
• Control unit 6 and decoupling switch 7 are in communication with the transmission line through a two-way line signal receiver/ transceiver circuit 13. Such a circuit is commercially available.
• decoupling switch 7 receives a signal from the line or mains, it will react to it according to its own address by switching the load ON or OFF.
• a decoupling switch 7 as shown in fig.
• a load current measuring sensor 14 connected through a current limiter circuit 15 with a controller 16 which controls a switch 17 (e.g. a relay) included in the load circuit.
• a load current, at which said switch 17 operates for decoupling the load from the circuit, is adjustable.
• a current measur ⁇ ing signal is passed from a digitizer 18 in digital form through a signal receiver/transceiver circuit 13 into the mains, from which the control unit 6 receives this load current signal as a feedback signal into the central processing unit 10 (CPU).
• CPU central processing unit
• control unit 6 is to investigate the state of a UPS system and, according to a desired program, to effect a controlled deloading as the charge of a battery is diminishing. Furthermore, on the basis of the current of an individual load, the control unit 6 can generate an alarm or to control the elimination of this load.
• the system is installed in a normal power distribution installation e.g. in an office premises, so that a UPS apparatus is coupled with those arrays of outlets which include data processing equipment or other critical loads.
• the UPS apparatus and control unit 6 can be fitted in the main or group centre 8 of a power distribution installation while the decoupling switches 7 are fitted in the outlets of load equipment.
• said decoupling switch 7 can also be fitted in a group line including a plurality of outlets.
• the UPS apparatus When the normal mains supply fails, the UPS apparatus begins an uninterrupted supply of loading.
• the control unit 6 through the intermediary of decoupling switches 7 cuts off the power supply ' to those loads that do not need back-up power electricity.
• the remaining critical loads receive electricity for a necessary period in a manner that their operations can be stopped in a controlled fashion and that the equipment requiring continuous operation are provided with an optimally long running time within the limits set by available battery capacity.
• the system control unit 6 communicates with outletwise or supply line wise decoupling switches 7 controlling them to open or close as necessary.
• said control unit 6 can control also other office equipment connected with the supply system and, on the other hand, it can receive information delivered from elsewhere (e.g. alarm centres of buildings) .
• the described novel solution is mostly competing with a decentralized UPS system.
• a decentralized system there is an individual UPS apparatus for each unit to be protected.
• the novel solut ⁇ ion includes following advantages:
• the novel system offers further possibilities in equipment development e.g. by giving additional functions to decoupling switches; short-circuit current limiting, measuring of current passing through a switch etc.
• the system and its components can be applied to direct- current systems, wherein especially the electronic short-circuit protection can be used to resolve present practical problems.

Landscapes

• Business, Economics & Management (AREA)
• Emergency Management (AREA)
• Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Stand-By Power Supply Arrangements (AREA)
• Power Sources (AREA)
• Charge And Discharge Circuits For Batteries Or The Like (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=8524338

Family Applications (1)

Country Status (4)

Families Citing this family (5)

Family Cites Families (5)

• 1987
  • 1987-04-16 FI FI871686A patent/FI871686A/fi not_active Application Discontinuation
• 1988
  • 1988-04-15 EP EP19880903258 patent/EP0358654A1/de not_active Withdrawn
  • 1988-04-15 JP JP50333588A patent/JPH02503861A/ja active Pending
  • 1988-04-15 WO PCT/FI1988/000054 patent/WO1988008218A1/en not_active Application Discontinuation

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events