Voltage Control Strategy Of DC Power Distribution Network

To ease the contradiction between supply and demand of global energy and environmental pressure and accelerate the "clean substitution and electric energy replacement", a large range of clean energy should be accessed to power distribution network to form "energy Internet". Distributed energy has the characteristics of intermittent and volatility, and the large scale of DGs being access to the distribution network may cause stability problems. Compared with the AC power distribution network, the DC power distribution network has no three phase imbalance, synchronization stability and other issues and it also has the advantages, such as a good adaptability to new energy, easy to constitute a multi-terminal system, low harmonic. So the DC power distribution network is more suitable for the construction of distributed energy. At the same time, the DC power distribution network based on the flexible direct current technology has more advantages than the AC power distribution network in terms of improving the power transmission capacity and improving the power quality. Therefore, in the future of distribution network construction, the DC power distribution network is an important research direction.In the DC power distribution system, the voltage stability of the DC is the same as the frequency stability of the AC system, which is of great significance. This article focused on how to optimize a DC voltage of the DC distribution network in stable operation and reduce distribution losses and how to maintain a DC voltage in the transient process stability are analyzed and studied. Firstly, the current distribution grid topology and control strategies are analyzed and put forward relevant method of DC distribution power flow calculation, and 14 nodes Case study calculated and analyzed; then the control command of DC power distribution is adjusted in stable operation to optimize the voltage distribution and reduce the network loss; then a simulation model of DC distribution system including distributed energy is built on PSCAD software platform. The DC power distribution network voltage stability mechanism on the transient process was analyzed, which made an effective transient voltage control strategies.