47results about How to "Taking into account the rapidity" patented technology

The invention discloses a flexible direct-current high-frequency resonance suppression method based on voltage feedforward nonlinear filtering. According to the invention, during the inner loop controlling process of a flexible direct-current current, the nonlinear filtering is carried out for a voltage feedforward link. The method specifically comprises the following steps: extracting each sequence component of an alternating-current voltage amplitude; calculating the N sampling point average values of the sequence components; comparing a current average value with the output result of a nonlinear filter in a previous period; and correcting the output result of the nonlinear filter in a current period. The output result is a fixed value which changes in a gradient mode and acts on the voltage feedforward link of the inner loop. The beneficial effects of the invention are as follows: the high-frequency resonance of a flexible direct-current and alternating-current system caused by impedance matching can be effectively inhibited. Meanwhile, the rapidity is achieved and the adjustment can be carried out along with alternating voltage when voltage disturbance such as alternating current faults occurs. The over-current risk of the converter valve is reduced. The method only needs to be achieved in the flexible direct-current secondary control software link, wherein no primary device needs to be additionally arranged. The method is low in cost, free of land occupation and convenient for engineering practice.

The invention provides a substation DC grounding inspection device with a line selection checking mechanism, relating to a device or method which detects an electric fault in a cable, transmission line or a network. The invention especially relates to an inspection device for detecting a substation DC system grounding fault. The device comprises an online monitoring automatic inspection control module and a group of inspection function modules. The inspection function modules comprise a DC bus detection module, a balanced bridge detection module, an unbalanced bridge detection module, a fault branch determination module and a line selection checking module. According to the state quantities of current voltage before and after a fault and the calculation amount of a grounding resistor and the electrical association among the three members, the fault feature recognition is carried out, an automatic inspection mode based on logic event driving is employed, a line selection checking function is integrated into the substation DC grounding inspection device with the line selection checking mechanism, an unbalanced bridge mode is called through logic judgment to identify zero drift and fault branches, and the wrong selection or missed selection of a DC grounding inspection device is quickly identified.

The invention relates to a substation DC power supply system, relates to a substation relay protection and automatic device, a DC power supply system powered by a telecontrol communication device and its protection, specifically a substation DC power supply system with the function of automatic ground fault inspection, Including a patrol control module, a DC bus detection module connected to the output end of the patrol control module, a DC branch detection module and a line selection check module; according to the state quantity of the current and voltage before and after the fault and the calculation quantity of the grounding resistance , and the electrical connection of the three, to identify fault characteristics, adopt the automatic inspection mode driven by logic events, integrate the line selection and verification function into the DC power supply system of the substation with the grounding inspection, line selection and verification mechanism, and pass the logic Judging and calling the unbalanced bridge mode to identify zero drift and faulty branches, and quickly identify the misselection or omission of the DC grounding inspection device.

The invention relates to an on-line monitoring device for DC power supply system of a substation, relates to a relay protection and automatic device of a substation, a DC power supply system powered by a telecontrol communication device and its protection, specifically a device with the function of automatic inspection of grounding faults The online monitoring device includes a patrol control module, a DC bus detection module connected to the output end of the patrol control module, a DC branch detection module and a line selection check module; Calculate the amount of resistance, and the electrical connection of the three, carry out fault feature identification, adopt the automatic inspection mode driven by logic events, and integrate the line selection and verification function into the substation DC power supply system with the grounding inspection line selection and verification mechanism In the process, the unbalanced bridge mode is called through logical judgment to identify zero drift and faulty branches, and quickly identify the misselection or omission of the DC grounding inspection device.

The invention relates to a wind power prediction method and system. The method comprises the following steps: step one, on the basis of historical data of a wind power, carrying out scene prediction and interval prediction on a wind power within preset time periods to obtain representative scene sets and the interval prediction results of the wind power during all preset periods; step two, withinthe preset periods, screening the representative scene sets within the same periods based on the obtained interval prediction results; and step three, connecting all screened representative scene setsof all preset periods according to a time sequence to obtain a daily wind power sequence with consideration of the time correlation, and carrying out wind power prediction based on the daily wind power sequence. With the method provided by the invention, the accuracy of prediction of the wind power is improved substantially; the calculation load is reduced; and the calculation efficiency is high.The wind power prediction method and system can be applei dto the wind power prediction field widely.