Broadcast channel testing

Testing a broadcast channel in which information is transmitted within a synchronous area of an electric power grid (100), whereby a characteristic relating to a frequency of power flowing in the electric power grid (100) is measured at a test receiver (121) and a signal based on a frequency modulation of the grid frequency is extracted from the electric power grid, and data indicative of a characteristic of the signal is sent to a control node (122) via a channel separate from the broadcast channel. Within the electrical power grid (100) there are transmitters (118) for transmitting information under control of a controller (122), and receivers (120) for receiving the information, such that the electric power grid (100) acts as a broadcast channel, and information is encoded by frequency modulation superimposed on the grid power frequency. Across the synchronous area of the electric power grid (100) the power frequency may be assumed to be essentially constant, such that the transmission ...

Broadcast channel testing

Device management in an electric power grid

Methods and apparatuses for controlling one or more electricity characteristics of electricity flowing in an electric power grid are described. Data indicative of a control function representing characteristics of a contribution to the one or more electricity characteristics to be made by a distributed plurality of power units during a control period is provided to the distributed plurality of power units. The power units individually determine and provide a contribution to the one or more electricity characteristics based on the received control function and profile information relating to the power units. This saves processing resources at the central location providing the control function and/or communications bandwidth/ resources. Instructions sent from a control node to power units may include a frequency-domain representation of the contribution. The control node may perform a transform process to transform the time- domain representation into a frequency-domain representation, the transform process comprising e.g. a Fourier Transform or a wavelet transform.

Broadcast channel testing

Methods and apparatus for testing a broadcast channel in which information is transmitted within a synchronous area of an electric power grid are described. A characteristic relating to a frequency of power flowing in the electric power grid is measured at a testing device and a signal based on a frequency modulation of the grid frequency is extracted from the electric power grid. Data indicative of a characteristic of the signal is then sent for receipt at a control node via a second channel different to the broadcast channel. This enables testing of the broadcast channel.