Simulation Research Of Light High-voltage Direct Current Transmission And Design Of The Experimental Equipment

With the new high-power electronic devices applied in power transmission, anew transmission technology named HVDC Light has been produced. Compared withthe traditional HVDC using phase control converters, HVDC Light puts VoltageSource Converters (VSC) into use, which are composed of IGBT devices andPulse-Width Modulation (PWM) technology. HVDC Light could reduce theequipments and simplify the structures of the converter station. It would have broadapplication prospect with couples of advantages such as low harmonics and flexiblepower control.This paper is focused on simulation research of Light High-Voltage DirectCurrent Transmission and design of its experimental equipment. For the independentcontrol of active and reactive power transmission, a mathematical model of the VSChas been constructed under the d qcoordinate axis. In order to prohibit theinterference of the cross coupling items, feed-forward compensation has been applied.With double closed-loop feedback control scheme, the Proportional plus Integral (PI)controller of the current inner ring and voltage and power outer ring have beendesigned with the transfer function. The simulation experiments of power control、multiterminal DC transmission and passive load power supply have been done usingthe Matlab/Simulink software. A HVDC Light Experimental Device with atransmission capacity of1500VA has been designed using PM75RLA120as thepower unit and TMS320F2812as the control chip. Also the parameter design of themain equipment, signal measurement and scaling circuit, drive and protection circuitof Intelligent Power Module (IPM), control circuit of Digital Signal Processor (DSP)have all been introduced in details. Unlike conventional DSP application developmentmethods, Matlab-DSP toolkit under integrated design environment which includesCCSLink and ETTIC2000has been used to complete the software design. This newmethod could directly generate the code from previous Simulink model, whose stepsare more clear and simple.