| 摘要 |
<p>A method of data communication on a power line in a deep sea hydrocarbon well facility where above sea a power signal half H-bridge A and a data signal half H-bridge B comprising respective DC supplies 12, 13 output respectively a power signal and data signal for combination and transmission over an umbilical line 20. Switches 15, 16, 18, 19 are independently operated by digital signal processors 14, 17 to generate AC waveforms from the DC supplies 12, 13 to form power and data signals using pulse width modulation. The low frequency power signal and high frequency data signal are combined and the voltage difference between them forms a communication signal that is transmitted to a subsea facility where data is extracted by discriminator 21 and power is provided to load 25. A data half H-bridge C at subsea level may transmit data topside using the same method. The system overcomes the problem of losses and data distortion inherent in systems using filters. Field programmable gate arrays or microcontrollers may alternatively be used as the modulation means.</p> |
