Research On Power Quality Monitoring Oriented Compressed Sensing Method

As Smart Grid technology developing, especially when more new energy accessed, more extra-high voltage applied and more various consuming load installed, electric power quality is facing increasing disturbance and instability factors. Therefore, how to keep the power quality becomes an widely focused problem. Data collection mode of power quality monitoring, which is the data source and information base, decides the efficiency and accuracy of power quality data measurement. In current situation, commonly used method to achieve the transmission of the sharply increasing data is compressing the sampled data information, through which the transmitted data can be largely decreased. However, there is still no way to depress the data amounts from source-side. The compressed sensing theory provides an effective way to solve the problem.To overcome the difficulties from huge amounts of collected data and limited front dealing capacity in traditional compressing method, compressed sensing theory is applied on power quality data collection, decreasing the data amounts and breaking through the dealing capacity bottleneck. In addition, a power quality monitoring oriented time-space compressed sensing method is proposed here, which considers the space correlation of data among similar consumers and the time correlation of data itself. The proposed method achieves a lower-dimensional compressed sensing and more accurate reconstruction via a transformation of sparse basis. Moreover, a optimized measurement matrix construction is also put forward here based on Kronecker product and Gram matrix, which promotes the non-correlation performance of measurement matrix, as well as the reconstruction accuracy and compress ratio. The simulation results shows that algorithms in this paper are effective to improve the compress ratio and reconstruction accuracy, which support power quality measurement method optimization and open a new way to achieve the widely quality monitoring in the whole process of power system.