5 results about "Prony method" patented technology

The invention provides a Prony algorithm-based cable segment wave velocity acquisition method, device and system, and a medium, and the method comprises the steps: testing a to-be-tested cable, and obtaining a cable signal transfer function; on the basis of the cable signal transfer function, in combination with cable joint distribution, constructing a cable signal approximation function based on a Prony method; constructing a linear prediction model of the cable signal based on the cable signal approximation function; performing denoising processing on the linear prediction model based on a singular value decomposition method to obtain a denoised linear prediction model; solving the denoised linear prediction model to obtain an attenuation coefficient; and calculating the segmented wave velocity of the cable based on the attenuation coefficient. According to the method, the Prony estimation method is combined with the singular value decomposition noise reduction algorithm, high-precision extraction of attenuation constants and segmented wave velocity decoupling are achieved, and then the electrical distance positioning precision is improved.

This invention discloses a 35kV power grid fault location method based on an improved Prony method, comprising the following steps: After a power grid line fault occurs, the protection device disconnects the circuit breakers at both ends to isolate the faulty line; transient excitation signals generated by capacitor discharge are injected into both ends of the line through the fault location module, and multiple data acquisition units simultaneously record the damped oscillating current signal to obtain two sets of multi-measurement point time series data; the improved Prony algorithm combined with symplectic geometric mode decomposition is used to process the data, and after phase space reconstruction and signal denoising, characteristic parameters such as attenuation coefficient and angular frequency are identified; the characteristic parameters are substituted into the equations of the line fault physical model to solve the problem, and the location result is output after statistical correction of the fault distance results at multiple measurement points. This invention equates the fault network to a second-order RLC damped oscillating circuit, and completely eliminates the influence of unknown transition resistance by using the difference method of the two-end measurement data, thereby improving the location accuracy.

The application discloses a kind of power system low-frequency oscillation characteristic signal extraction methods, comprising: the electrical variation data of acquisition each generator outlet is preprocessed;Through complementary ensemble empirical mode decomposition, variation data is decomposed, and noise component is filtered out;SPA smoothing algorithm is used to process the electrical variation signal after denoising;Prony method is used to decompose the signal after smoothing, and the amplitude and phase of each frequency component are extracted;The application has more excellent noise suppression capability and signal fidelity, can effectively solve the problem of modal aliasing, can adaptively identify and filter out various noise components, and shows good adaptability to noise interference under different operating conditions of power system;SPA smoothing algorithm reduces the error introduced by complementary ensemble empirical mode decomposition while effectively retaining the key features of low-frequency oscillation;Combined with Prony method, the characteristic parameters of the oscillation signal can be accurately extracted in a strong noise environment, providing a reliable data basis for low-frequency oscillation source identification.

The application discloses a transient fault ride-through and reactive power collaborative control method based on a bionic nerve reflex mechanism and belongs to the technical field of power systems, which comprises the following steps: a power system dynamic model under a large amount of new energy injection is established; a simulation nerve reflex control model is established, and target reference trajectories and control parameters of reactive power equipment in cooperation with traditional electric fields are confirmed; a low-voltage ride-through control system of a high-proportion new energy power grid under the cooperation of reactive power equipment and traditional electric fields in a fault is established; an optimal control sequence for recovery to a steady state after low ride-through under a fault is solved, and current control values are output; ride-through evaluation of reactive power equipment in cooperation with traditional electric fields in a high-proportion new energy system based on a Prony method is performed; and system control parameter collaborative optimization considering an expected disturbance scene is performed. The transient fault ride-through and reactive power collaborative control method based on the bionic nerve reflex mechanism provides an efficient and reliable transient fault ride-through solution for a high-proportion new energy power grid.

The invention discloses a power transmission cable metal sheath grounding fault on-line diagnosis method, which comprises the steps of S1, dividing a to-be-detected high-voltage power transmission cable into a plurality of sections, defining one end of the to-be-detected section of the high-voltage power transmission cable as a head end, and defining the other end of the to-be-detected section of the high-voltage power transmission cable as a tail end; s2, a distributed circulating current detection device is installed on the high-voltage power transmission cable to be detected; s3, collecting a current signal on the to-be-detected section of the high-voltage power transmission cable by adopting a distributed circulating current detection device, and estimating the amplitude and phase of the collected current signal by adopting a Prony method; s4, synchronizing current phases of all the distributed circulating current detection devices mounted on the high-voltage power transmission cable to be detected; and S5, calculating characteristic currents, comparing the amplitudes, phases or vectors of the calculated three groups of characteristic currents, and judging that the cable sheath has a grounding fault when data are inconsistent in comparison. When the method is applied, accurate diagnosis of the ground fault of the metal sheath of the high-voltage power transmission cable on site can be realized.