Abstract: Exemplary embodiments are directed to use of transparent transmission of teleprotection commands in the form of GOOSE or GSSE messages, as defined by the Generic Substation Event class model by the standard IEC 61850, between substations combined with Channel Supervision and Monitoring equivalent to CSM offered by known teleprotection equipment. This approach avoids the disadvantage of non-transparent transmission when using the gateway approach and of the lack of the CSM functionality when using the tunnelling approach.

Abstract: Data transmission is disclosed over a transmission channel that is subject to narrowband interferers. An increased overall bit or data transmission rate is achieved by an exemplary method of determining a channel capacity of plural sub-channels of the transmission channel based on a net background noise power estimation. The net background noise power contains only white noise-like contributions and excludes, to a reasonable extent, noise contributions or signal power from narrowband interferers. Hence, the net background noise power can be reduced. For example, an Orthogonal Frequency Division Multiplex (OFDM) signal code construction or bit allocation scheme can be chosen that provides for optimized data transmission at a data rate that approximates or approaches the more realistic channel capacity of an individual sub-channel, resulting in an increased overall bit or data transmission rate.

Abstract: A method and modem are provided for obtaining an optimized efficiency of an Orthogonal Frequency Division Multiplex (OFDM) data transmission, such as for power line communication, for example. The length or duration of a guard interval or cyclic prefix in an OFDM symbol is newly selected at each start-up of a modem while initializing or preparing the OFDM data transmission. The length of the guard interval can be given by the number of samples in a time-discrete representation, and the value of such number of samples that is retained for the subsequent data transmission can be selected from a plurality of pre-determined possibilities based on an evaluation of a channel quality of a communication channel including a physical line to which the modem is connected. Hence, the selected value depends on actual transmission conditions, and the optimization potential offered by a more flexible handling of system parameters is exploited to meet changing conditions on the physical line.

Abstract: A method is disclosed for transmission of commands or command combinations via a communication link by coded frequency-shift keying. Each command or command combination is associated with one frequency pair. When a command changes from a preceding command or command combination to a subsequent command or command combination, one frequency (which will be the first to be transmitted) in the frequency pair of the subsequent command or command combination is chosen as a function of at least one other associated frequency pair.

Abstract: A method and modem are provided for obtaining an optimized efficiency of an Orthogonal Frequency Division Multiplex (OFDM) data transmission, such as for power line communication, for example. The length or duration of a guard interval or cyclic prefix in an OFDM symbol is newly selected at each start-up of a modem while initializing or preparing the OFDM data transmission. The length of the guard interval can be given by the number of samples in a time-discrete representation, and the value of such number of samples that is retained for the subsequent data transmission can be selected from a plurality of pre-determined possibilities based on an evaluation of a channel quality of a communication channel including a physical line to which the modem is connected. Hence, the selected value depends on actual transmission conditions, and the optimization potential offered by a more flexible handling of system parameters is exploited to meet changing conditions on the physical line.

Abstract: Data transmission is disclosed over a transmission channel that is subject to narrowband interferers. An increased overall bit or data transmission rate is achieved by an exemplary method of determining a channel capacity of plural sub-channels of the transmission channel based on a net background noise power estimation. The net background noise power contains only white noise-like contributions and excludes, to a reasonable extent, noise contributions or signal power from narrowband interferers. Hence, the net background noise power can be reduced. For example, an Orthogonal Frequency Division Multiplex (OFDM) signal code construction or bit allocation scheme can be chosen that provides for optimized data transmission at a data rate that approximates or approaches the more realistic channel capacity of an individual sub-channel, resulting in an increased overall bit or data transmission rate.

Abstract: A method is disclosed for transmission of commands or command combinations via a communication link by coded frequency-shift keying. Each command or command combination is associated with one frequency pair. When a command changes from a preceding command or command combination to a subsequent command or command combination, one frequency (which will be the first to be transmitted) in the frequency pair of the subsequent command or command combination is chosen as a function of at least one other associated frequency pair.

Abstract: In a method and a detector (7) for time-optimum reception of protection commands in a remote tripping device, at least two detector elements (1, 2) are operated, which are all designed for a signal at the same frequency but for different transmission times. Where at least one of these detector elements (1, 2) detects the presence of the signal, the signal is regarded as having been detected.

Abstract: In a method and a detector (7) for time-optimum reception of protection commands in a remote tripping device, at least two detector elements (1, 2) are operated, which are all designed for a signal at the same frequency but for different transmission times. Where at least one of these detector elements (1, 2) detects the presence of the signal, the signal is regarded as having been detected.

Abstract: A detection circuit for remote release apparatus is disclosed which monitors a circuit carrying high-voltage between two connection points A and B and disconnects the circuit from the rest of a high-voltage network by automatically opening two power switches when a short circuit is detected. The ground fault protection system includes a pair of power switches for disconnecting points A and B from the remainder of a high-voltage network when a fault is detected in the high-voltage carrying circuit. A different one of a pair of detection circuits are associated with each point A and B. Each detection circuit causes both power switches to open when a fault is detected. The fault detection circuit associated with point A detects faults occurring in the high-voltage carrying circuit at any location extending from point A to at least one-half a distance to point B.