The Measurement Of Harmonic Current In HVDC

The HVDC(High Voltage Direct Current) transmission is playing an more and more important role in the national economy of our country.In HVDC system, It is meaningful to search for a new way to mearsure the harmonic current.This text is based on fully analyse the measurement of harmonic current in HVDC system.Use the Rogowski coil as the sensor and transmit the signal and energy with the optic fibre, analyse the principle of the measurement of harmonic current in HVDC system and the factors of its measurement of influence by opticelectricity and computer technology.The Rogowski coil is used to measure the harmonic current in HVDC system. It doesnot affect by direct current and has good frequency characteristics. Structure and performance of the Rogowski coil based on PCB is researched in this text.The sensor is designed by the request of the system.It is very simple for the Rogowski coil based on PCB manufacturing , winding the line intensivly, well-balancedly,high accuracy and of good performance,not induced by direct current.It is very suitable for harmonic current measurement.The low-voltage side is used to analyse certain order of harmonic current using FFT which is written in DSP chip F206.It will fasten the operation of F206 and economize limited resources by adding the interpolation algorithm.optic power supply request and low consumption of the high-voltage side determinate the performance of the system. The low consumption chips are used to reduce the power consumption notably on the high-voltage side. Optic power supply solved problem of power supplies in the technology on the high-voltage side.The measuring request are mentioned and performance of the system of harmonic current measurement in HVDC is tested. The result indicates that the accuracy of the whole system is very high.It can be used for measuring certain order of harmonic current in the power network of HVDC.