37 results about "Superposition theorem" patented technology

The application discloses a kind of stray current interference under constant potential instrument output adjustment method, steps include: setting target pipe section, setting monitoring point, closing constant potential instrument, calculating average inflow and outflow current density, performing test measurement, obtaining relationship curve, obtaining acceptable preset current range, performing preset current adjustment.In the embodiment of the application, the curve of the off-power potential and the negative protection current is obtained, and the superposition theorem is used to obtain the test piece current density of the negative protection standard range boundary, which is superimposed with the inflow or outflow current during interference to obtain the off-power potential during interference. The preset current of the constant potential instrument in the negative protection standard range is obtained by using the obtained off-power potential and the preset current curve, and finally the constant potential instrument operates according to the obtained preset current. The pipeline can maintain negative protection standard under interference, and the whole process does not need manual setting, the requirement for personnel is low, and the negative protection effect of the pipeline can reach the best state.

The invention relates to the technical field of power distribution network loop closing, in particular to a novel power distribution network loop closing current calculation method considering comb load equivalence and reactive compensation access, which comprises the following steps: S1, acquiring an equivalence distance and an equivalence point electrical quantity of a comb load; s2, line impedance and load equivalent impedance are obtained based on the equivalent distance and the equivalent point electrical quantity of the comb-shaped load, and a loop closing current calculation model is constructed based on the line impedance and the load equivalent impedance; s3, acquiring loop closing steady-state current based on the superposition theorem and the loop closing current calculation model; s4, acquiring loop closing transient current based on an optimal frequency method; and S5, constructing a simulation verification model to verify the stability of the loop closing current after the new energy is accessed. For the closed-loop steady-state current, the comb-shaped load equivalence method provided by the invention can well keep the original electrical characteristics of the circuit, and reasonably processes the reactive compensation equipment. The error between the loop closing current steady-state calculation value and the actual simulation value is within 2%.

The invention relates to the technical field of new energy power generation and electric power system planning and operation, and particularly provides an offshore wind power networking unit configuration method considering economy and stability. The method comprises the following steps: constructing a wake flow matrix between units; establishing an economic model containing wake effect differentiation opportunity cost; constructing a bimodal network based on the superposition theorem to calculate a generalized system strength index, and deducing a critical short-circuit ratio threshold value; and constructing a collaborative optimization model taking net income maximization as a target, and solving an optimal locating and sizing scheme of the deconstruction network unit under the constraint of system strength. According to the method, the idle capacity of the wake flow area is utilized, stability and economy cooperation is achieved, and the full-life-cycle income is improved.

The invention relates to a direct current power transmission system-oriented fault initial wave process analysis method and equipment. The method comprises the following steps of: calculating time delay of a propagation function minimum phase system; processing the rational fraction of the propagation function and the rational fraction of the wave impedance by adopting a discrete recursion convolution method in combination with the time delay of the minimum phase system of the propagation function to obtain a low-order dispersion equivalent voltage source recursion, and integrating into a high-order dispersion equivalent voltage source recursion of the propagation function according to a linear time-invariant system superposition theorem; a wave impedance equivalent voltage source and transmission line equivalent resistance are obtained by combining the recursion law of the RC parallel network; constructing a direct-current transmission broadband Bergeron equivalent calculation circuit; and analyzing the fault initial wave process by using a direct-current transmission broadband Bergeron equivalent calculation circuit. The method can be suitable for any sampling rate, transition resistance, fault position and fault type, and good precision is kept within 10-20 ms after disturbance occurs.