Research On Reactive Power Compensation Control Strategy In High Voltage Distribution Network

In the 21st century, with the energy costs rising. clean energy and green production technology impact on the environment are of concern. In this situation.how to reduce the new transmission line losses, how to stabilize the power transmission capacity become the electric power industry's key issues. With the application and upgrade of the flexible AC transmission (FACTS) technology, which can control the transmission lines' rces. Therefore, the study design of FACTS control devices have become increasingly important.Reactive power compensation devices control the power system in several ways. First, controling the system voltage,which make the system voltage stable within the expected. Second,controling the reactive current or power,which make they stable within the expected. The third one is a comprehensive control,making the power system voltage,reactive current or power, static transient stability, and damping oscillation stable in the desired range.The replacement of the reactive power compensation equipment,actually is the promotion of the controling strategy. Therefore,the design of scientific. effective control strategy is the key. This paper studies the control strategy and methods of ancient FACTS, make the substation in Anshan as the test base, designs simulation of SVC control strategy builds substation equivalent circuit model, through using the components in RTDS system component library.use actual SVC device regulation unit to generate the trigger pulse signal, and input signal through the RTDS input channel, control the TCR thyristor conduction. Meanwhile, the model 35kV,66kV bus voltage value in the RTDS system via D/A converter,it real-time input into the actual device through the output terminal by the form of analog, form a closed loop of the physical-aspects of digital simulation.In the test, by setting the timing control switching load which caused 66kV bus voltage fluctuations verify that the actual SVC device control strategy is validity in maintaining the 66kV bus voltage among 65.3kV to 66.6kV. According to the status of the first red in the power system and its load characteristics, the study obtained that the SVC of red substation can reduce system losses,adjust the voltage inhibit voltage fluctuations and stabilize the load shock.It can improve the power quality. Through the design simulation of the STATCOM control strategy, the study obtained that STATCOM's operating range and adjusting rate are faster and wider than SVC. Through the three-phase power system transient simulation design, the study obtained that TCSC can control the line trend, improve power system transient stability, and can hinder the line power oscillation. Compared with SVC, it has a flexible controling ability. Through analysis the power system stability and control performance,it obtained that SSSC as a pure reactive power compensation, the voltage source phase is always perpendicular to the line current. Therefore, injecting a real-time alternating positive and negative virtual active resistance into a line,it can sink or provide active power which corresponding to the mechanical oscillations that play a major role.The important is that SSSC does not cause SSR, and can hinder sub-synchronous resonance that causes by other series capacitor in transmission network. By studying PID fuzzy control method.it shows UPFC can be complete to control active and reactive power flow, transmission lines can transmit more power with a smaller loss.Through the above comparison of several control devices, it can be seen.that FACTS devices and power system control design method is the key. Reducing control equipment costs and establishing an effective control method for the future power systems will play a crucial role in the output loss. Among them, this paper takes the red substation in Anshan of Liaoning Province as an example,make a SVC operation simulation. SVC fill the gap,which invent power output compensation device by our own. narrow the gap with the world's leading, provide a scientific basis and accumulate design experience for our energy power system,promote a good and fast development of China's power industry.