DEVICE AT TELECOMMUNICATION SYSTEM

Abstract: The present invention relates to a device at telecommunication network for distribution of electric power to exchanges, nodes and customer located equipments. Distribution of electric power to the telecommunication network is made to exchanges and nodes via a public electric power distribution network. At least exchanges in pairs obtain power feed via of each other independent power distribution routes. The exchanges/nodes in pairs in addition exchange control information. At power failure in an exchange/node, the other exchange/node will still be functioning. When the power distribution is back, data stored in the parallel exchange/node will be transferred. Restart of the exchange/node after that can be made, and at shorter power failures a break in the communication is obtained which is not perceived, or is acceptable to the communicating persons.

Description: TITLE OF THE INVENTION Device at telecommunication system. TECHNICAL FIELD The present invention relates to supply of electric power to parts belonging to a telecommunication system and terminal equipments . PRIOR ART Supply of electric power to exchanges and nodes in the telecommunication systems of today is made via rectifiers. The rectifiers are connected locally to the public electric distribution network. At power failure, storage batteries take over, without any break, the distribution of electric power to the exchanges and the nodes. The time during which the exchanges will function is limited to a number of hours independent of the traffic load. The ordinary telephone sets get their power supply from the storage battery of the telephone exchange. Advanced terminal- and subscriber equipments, which nowadays are often computerized, normally get their supply of electric power straight from the electric power distribution network without battery back¬ up. These subscriber equipments will immediately be disabled when there is a power failure in the public electric power distribution system. In certain cases a back-up power station can be connected. These back-up power stations are driven by for instance diesel engines and are fixed installed, or mobile. At longer power failures such reserve power stations can be transported to a wanted place to supply for instance an exchange with electric power. Such an effort implies that traffic chaos is not prevalent, so that the back-up power station within a reasonable period of time can be transported to the place in question. At different critical states in society this condition is not probable. DESCRIPTION OF THE INVENTION TECHNICAL PROBLEM Battery back-ups which are arranged at exchanges and nodes are expensive at acquisition and maintenance. They require continuous attention and checking of function to continuously be in a state of alert for its task. The length of life of the batteries is further limited in time, and varying at random. The program controlled exchanges of today also must be restarted m the cases that shorter breaks m the distribution of electric power occur Such restarts cause m present systems total standstills during at least about 20 minutes. Terminal- and subscriber equipments located at the subscriber and which are directly dependent of the public electric distribution network will, during a power failure, be completely or partially unusable. Consequently there is need to find solutions where the above mentioned problems can be eliminated or at least be limited. With the heavily growing number of exchanges and nodes in the telecommunication network, unaccessability and costs in connection with failures in the power distribution to the telecommunication network and its terminal- and subscriber equipments will increase and become considerable with present strategy. The present invention has the aim to find a solution to the problem. THE SOLUTION The present invention relates to a device at telecommmum- cation network equipped with electronic storage devices The telecommmunication network is further equipped with a distribution of electric power which has been transformed from a public electric power distribution system. In the distribution of electric power, shorter breaks can occur The breaks in the power distribution can cause breaks m the present communication. In the telecommmunication network such units as exchanges, nodes, terminal equipments etc are included. The information which controls the telecommunication traffic in the network is stored in at least one unit in addition to the utilized unit. The at least two units obtain distribution of electric power for their respective functions via of each other independent distribution routes. Traffic information over/via a a first unit is also stored in at least one second unit. Traffic information which has been lost in the first unit, at for instance power failure, can be transferred to the first unit, which at that is updated, and continued communication is allowed after the cease of the power failure. The traffic information which is stored, respective transferred between the units in the telecommunication network, consists of for the network necessary information for maintaining and establishing communication. In the telecommunication network there further is arranged a distribution of electric power which supplies electric power to a number of geographically separate units. From the public electric power distribution network is at that a voltage transformed which is distributed to the geographically separate units. At the geographically separate units the distributed voltage is after that transformed to for the local need adapted voltages. The distributed voltage is distributed via one with the telecommunication network preferably parallelly arranged power distribution network. The power distribution network is preferably arranged in ring structure . ADVANTAGES The suggested solution allows that the need of batteries at exchanges and nodes can be minimized. This results in a reduced cost for batteries and for maintenance. In the case that electric power distribution to certain exchanges and nodes during longer power failures is not regarded as necessary, these telecommunication networks instead can be connected locally to the public electric distribution network without battery back-up. By introducing a separate power distribution network which supplies a multiple of geographically separate units with electric power, also centrally located stand-by power stations (fixed or mobile) can supply a large number of exchanges, nodes and base stations with electric power also at very long breaks in the public distribution of electric power (weeks to months) . The accessibility and the operating stability is increased independent of the public distribution of electric power, and the back up times can be extended considerably in relation to the situation of today. At the customer located and computerized subscriber and terminal equipments also can be offered a supply of electric power independent of the public power distribution network. The customers of the telecommunication network in this way are given a limited distribution of electric power to the telecommunication equipments at power failure and can continue to communicate. The utilization of the telecommunication network during a limited period of time is today given during power failure for ordinary telephony where the equipments do not require supply of power from the public power distribution network. Data traffic and multimedia services which require electric power supplied terminals are however broken at power failure. The suggested solution allows that all types of telecommunication equipments can be offered to continue to work at power failure in the public electric power distribution. Loss of traffic and information at power failure is limited or is eliminated completely. Any losses in message information is kept at an acceptable level. At the take over of the distribution of electric power in a second electric power source, short breaks in the communications can occur. The information which is required for keeping up the traffic is however rapidly recoverable after the power failure. The recovery of lost information is transferred from the exchange/unit which is arranged to parallelly store the traffic information. The transferred message information which may be lost is hardly perceptible. The invention consequently gives a telecommunication system which is tolerant towards errors and independent of the public electric power distribution. Today's high demands for accessibility is fulfilled with lower operative expenses for the power distribution in the telecommunication network. DESCRIPTION OF FIGURES Fig. 1 shows the distribution of electric power to included units of a telecommunication system of today. Fig. 2 shows the ring network structure for distribution of electric power to units in the telecommunication network. Fig.3 shows a schematical picture of the distribution of electric power in a telecommunication system according to the invention. DETAILED EMBODIMENT In the following the invention is described on the basis of the figures and the designations in them. A telecommunication network includes a number of units El, E2, E3, ....EM which are voltage fed via transformer devices Tl, T2, T3... TN. The transformer devices are voltage fed via a number of transformers TR1, TR2 etc. The transformers TR1, TR2 etc in their turn are voltage fed from the electric power distribution networks EN1, EN2 etc. The electric power distribution network consists of parts EN1, EN2 etc which are independent of each other. If, for instance, the electric power distribution network EN1 is disabled, the electric power distribution network EN2 will probably function. In ordinary telecommunication systems all units EN1, EN2 will be disabled at power failure, whereas the units which are voltage fed via the electric power distribution network EN2 are still functioning. In ordinary telecommunication systems according to Fig.l, electric power supply is obtained from one or more suppliers of electric power. The distribution of electric power to the units Tl, T2 and T3 is obtained via the supplier of electric power EN1. The distribution of electric power to the units E4, .. , EN is obtained from the supplier of electric power EN2. Breaks in the distribution of electric power cause breaks in the functionality of the units El, E2 , E3 etc. In the ordinary construction of telecommunication networks important units are equipped with battery back-ups which take over the distribution of electric power during a limited period of time. If this time is exceeded, the unit will stop functioning. In such cases, or if shorter breaks in the distribution of electric power occur at the establishing of connection between the electric power distribution systems, programmed data can be partly or completely lost. To get the unit back in usable condition after that, requires updating of lost data. Affected communications must after that be re-established by respective communicator. A number of supplies of electric power EN1, EN2 etc are arranged where the delivered voltage is transformed to a suitable voltage in the transformers TRl, TR2, etc. The transformed voltage is adapted to a voltage which can be transported in the electric power distribution network, LE, over a wanted distance. The power which can be taken out from the electric distribution network in question, LE, is further adapted to the power consumption which can arise in the current case. The distribution of electric power over the electric power distribution network LE consequently is made via a number of independent electric power distribution routes EN1, EN2 etc, and to make it possible for the electric power distribution to function acceptably, voltages, frequencies, phases etc are adapted to each other. The construction in this respect is in accordance with the construction of ordinary public electric power distribution networks. In other variants the electric power distribution can be managed by for instance electric power distribution route EN1 via transformer EN1. At break in electric power distribution via EN1, this is sensed at the connection point for, for instance, EN2. When a break in the electric power distribution has been observed, a switching in the electric distribution network LE is made over the switch K, at which the distribution of electric power is made via transformer TR2. A distribution of electric power with principally no break is at that achieved, but at the switching, break can occur which destroys the memory content in one or more of the units E1, ...E3. To bridge this difficulty, for instance unit EN1 continuously exchanges information with unit EN2. All information regarding current communication and subscriber data etc is consequently stored on at least two of each other independent places in the telecommunication network. Transfer of data is made either over the ordinary transport routes of the telecommunication network, or over dedicated lines only intended for information interchange between the units . At a break in the distribution of electric power from EN1, the distribution of electric power is taken over by EN2. At the connection of EN2 a shorter break in the distribution of electric power to the units El, E2 and E3 can occur. These units at that can lose information which is of importance for the communication. If this occurs, the units EMI...EM however has stored information regarding data and traffic in the units El, E2 and E3. In the case that only a smaller part of the traffic information has been lost, the lost information is transferred beween for instance El and EMI. After the updating El re-establishes the communications which have previously been established. This is made within a space of time which by the communicators are experienced as if no break has occurred; however a disturbance in the communication can possibly be perceived. The invention is not restricted to the in the example above shown example, or by below specified patent claims, but my be subject to modifications within the frame of the idea of the invention.

Claims: PATENT CLAIMS 1. Device at telecommunication network, equipped with storing possibility in electronic storage devices, equipped with distribution of electric power, which distribution of electric power is arranged to be transformed from an electric power distribution network, c h a r a c t e r i z e d in that shorter breaks in the distribution of electric power can occur, which shorter breaks in the distribution of electric power can cause breaks in current telecommunication traffic, that the telecommunication traffic is arranged to be restored within such a short period of time that the telecommunication traffic is experienced as unaffected. 2. Device according to the previous patent claim, c h a r a c t e r i z e d in that in the telecommunication network included units are arranged to consist of, for instance, exchanges, nodes and terminal- and subscriber equipments . 3. Device according to patent claim 1 or 2, c h a r a c t e r i z e d in that information which controls the telecommunication traffic is arranged to be stored in at least two units in the telecommunication network. 4. Device according to any of the previous patent claims, c h a r a c t e r i z e d in that the at least two units obtain the distribution of electric power via essentially different power distribution routes. 5. Device according to any of the previous patent claims, c h a r a c t e r i z e d in that information about a first unit is arranged to be stored in at least a second unit, and that information which has been lost in the first unit can be transferred between the second and the first unit. 6. Device according to any of the previous patent claims, c h a r a c t e r i z e d in that the first unit is arranged to re-establish the broken communication. 7. Device according to any of the previous patent claims, c h a r a c t e r i z e d in that a multiple of the units which are geographically separate are arranged to obtain the distribution of electric power from one or more common electric power distribution points in which electric power distribution points also back-up power plants can be arranged. 8. Device according to any of the previous patent claims, c h a r a c t e r i z e d in that the electric power distribution system is arranged to include a first voltage transformed from the electric power distribution network/back-up electricity plant, and a second voltage is arranged to be transformed from the first voltage at the geographically separate units. 9. Device according to any of the previous patent claims, c h a r a c t e r i z e d in that the first voltage preferably is of high voltage, and the second voltage preferably is adapted to a local need. 10. Device according to any of the previous patent claims, c h a r a c t e r i z e d in that power distribution to the exchanges and nodes can be arranged without batteries and that distribution of electric power is arranged to be made directly from the public electric power distribution network. 11. Device according to any of the previous patent claims, c h a r a c t e r i z e d in that the first voltage is arranged to be supplied to the geographically separate units via preferably a ring network, which ring network is arranged parallelly with the telecomunication network.

Inventors: AAKERLUND JOHN, HAGSTROEM BENGT, LENNMARKER NILS, AAKERLUND, JOHN, HAGSTROEM, BENGT, LENNMARKER, NILS
Applicants: TELIA AB
Application year: 1997
Main classification: H04M3
IPC codes: H04M19