Application Of Improved Soft-Measurement Method Based On Neural Network Inversion In Power System Control

As an available method, inversion method is widely applied in various field for its advantage of clear physical idea, simple structure and facile realization. However, in practical, inversion method often requires the feedback of immeasurable variable, which is an obstacle of application of inversion method. Therefore, a method for avoiding feedback of immeasurable variable is proposed in this paper by improving ANN soft-sensoring method and combining it with inversion method. Then, this method is applied in power systems control. Under the support of the National Natural Science Foundation of China, this paper obtains some progresses, as follows:(1) An improved method for ANN soft-sensoring which is presented previously by our research group. In the improved method, measurable process variables required for"assumed inherent sensor"inversion method are expanded to measurable function of process variables. Based on this method, arithmetic to construct"assumed inherent sensor"and the example of arithmetic are presented. The improvements of the method make it more possibly to construct the"assumed inherent sensor".(2) To avoid high-order derivative of directly measurable variable, a improved arithmetic process based on"assumed inherent sensor"inversion is proposed. Compared with the previous arithmetic, the derivative order of directly measurable variable in new arithmetic is lower than that in previous arithmetic, which makes the soft-sensoring method based on"assumed inherent sensor"inversion easily to realize in practical engineering.(3) To solve the problem that the sample data for training ANN is difficult to acquired, an available method is presented.(4) An algorithm to construct the"assumed inherent sensor"inversion in multimachine is presented for the special form of mathematics model in multimachine, which makes it possible that the ANN soft-sensoring method can be applied in multimachine power systems control.(5) To verify the validity of the method proposed, in practice, we research the excitation control of power systems with one machine infinite bus and the excitation and valve control of multimachine in power systems, and the method proposed is verified by computer simulation.