This application claims the priority of German patent Application No. 199 16 452.5 filed Apr. 12, 1999, which is incorporated herein by reference.
This invention relates to a power ring that has an annular conductor structure and is installed in a vehicle, particularly a military vehicle, for supplying devices in the vehicle with electric energy. The power ring includes a plurality of controllers functioning as monitoring and switching devices that are connected along and on an annular conduit, as well as a plurality of taps on the annular conduit for connecting the respective devices with the annular conduit. The power ring includes feed locations along the annular conduit for supplying electric energy and data connections between the controls, and a superordinated control device for monitoring and controlling the power ring.
Reliably supplying electric energy to devices which are individual components that consume electric power in a vehicle, particularly in a military track laying or wheeled vehicle, is effected increasingly by means of a xe2x80x9cpower ringxe2x80x9d in which, in contrast to a star-like connection of each load (electric energy consumer) to a generator, an annular conduit that conveys the energy connects each electric load with the current producer or the generator.
A short circuit on the annular conduit of the power ring results in an interruption of energy supply of all the loads connected to the power ring. Then, conventionally, a repair workshop is visited to eliminate the defect. In particular for applications in military vehicles, however, an interruption of the internal current supply to all devices connected to the power ring because of a simple short circuit is undesirable and not permissible.
Conventional solutions provide to subdivide the power ring into individual segments by means of a power ring controller. The devices are connected to the segments of the power ring by taps on the power ring. In case of a short circuit in one segment, only those devices that are connected to the respective segment are affected by the short circuit and become inoperative. The devices connected to the other segments of the power ring continue to be supplied with electric energy and thus continue to remain functional.
German patent document 197 33 760 discloses, in connection with a data bus for information transmission, that transmitter and receiver components connected to the bus conduit at nodes may switch on a terminal resistance at each node, and further switches may be placed at the node so that a device connected to the node may be disconnected from the bus conductor in case of a defect, while the remaining bus operation is not affected by the failure of one node.
The conventional solutions have the disadvantage that by dividing the power ring into ring segments, in case of a failure the defective power ring segment is switched off by means of the power ring controller, as a result of which the devices connected to such a segment are no longer supplied with electric energy. In case of a small number of segments as well as controllers and the same number of devices, such a disadvantage is even greater because a relatively large number of devices fail with a single segment because a greater number of devices per segment is supplied with electric energy.
A redundancy construction of the power ring may be remedied for a device breakdown in case of individual failures. Such a construction, however, requires substantial outlay and is disturbance prone because an additional failure sensing has to be provided and the number of the power ring components are doubled.
It is an object of the invention to limit the effect of a short circuit in a power ring in such a manner that only a few connected devices fail, that is, a possibly large number devices are not affected by a simple short circuit. A simple possibility should be found to continue to supply all devices with electric energy despite a breakdown of a power ring segment also viewed as a connecting conductor, at least for failure number one (single failure case).
The above object generally is achieved according to the present invention by a power ring of annular conductor configuration for use in a vehicle, preferably a military vehicle, to supply electricity to devices in the vehicle, with the power ring including: a plurality of controllers as monitoring and switching devices arranged along and connected with a plurality of conductor segments connected to form an annular conductor; a plurality of taps provided for connecting the annular conductor to loads; at least one feed location connected to the annular conductor for feeding electrical energy to the annular conductor and to the loads; and data connections from the controllers to a superordinated control apparatus for monitoring and controlling the power ring; and wherein: each tap and feed location for the annular conductor is structurally combined as a unit with a controlled node of a respective controller; each tap controller is connected along the annular conductor and into the annular conductor in a multiple manner so that the annular conductor segments are disposed between adjacent tap controllers, and at least one load or a current feed connected to a tap controller is selectively connectable with adjacent conductor segments of the annular conductor via a plurality of controlled switches disposed at the tap controller of the respective controller with which the respective annular conductor segments may selectively be connected to or disconnected, and with which the respective load or the feed may selectively be connected or disconnected.
According to the invention, the power ring is provided with its structural elements in such a manner that the power ring controller and the power ring tap are combined into a common system unit and device. The thus-formed tap controllers are interconnected with conductors as a power ring in such a manner that the devices to be supplied with electric energy need only to be connected to the tap controller. In case of a failure, one segment of the power ring which is situated between two tap controllers, is switched off, and all devices which are connected to the tap controllers may be continued to be supplied. In case the failure concerns only the power ring conductor, all devices continue to be supplied because these are only connected to the tap controllers and the annular conductor continues to be closed via the remainder of the ring. Only in case of a failure of a tap controller is that portion of the devices which is coupled to the controller no longer supplied. Such a condition would appear also in case of two conductor segment failures. In case of a single conductor segment failure or isolated individual failure, however, all devices continue to be supplied by the power ring according to the invention.