38results about How to "The principle of ranging is simple" patented technology

The invention discloses a method for ranging a single-phase earth fault of a line by using single-end electric quantity. The method comprises the steps of measuring the fault phase voltage, the fault phase negative sequence current, the fault phase current and the zero sequence current in a transmission line protection mounting location; calculating an imaginary part of the ratio between the fault phase voltage and the fault phase negative sequence current; calculating an imaginary part of the ratio between potential drop per unit length of the transmission line and the fault phase negative sequence current; and dividing the imaginary part of the ratio between the fault phase voltage and the fault phase negative sequence current by the imaginary part of the ratio between the potential drop per unit length of the transmission line and the fault phase negative sequence current to obtain the fault distance from the transmission line protection mounting location to the single-phase earth fault point. The method uses the single-end electric quantity to achieve accurate measurement of the single-phase earth fault distance of the transmission line, overcomes the influence of transition resistance and load current on the fault distance measuring accuracy, the ranging principle is simple, the program is easy to achieve, and the method has the advantages of small calculation amount, high ranging speed and high real-time performance.

The invention discloses a line single-phase ground fault single-terminal location method capable of preventing influences of both transitional resistance and load current. According to the method, the voltage phase angle of a single-phase ground fault point is calculated by utilizing the fault-phase negative sequence voltage of the relay location of a transmission line and the positive sequence impedance of the transmission line per unit length; the imaginary part of the voltage drop from the relay location of the transmission line to the single-phase ground fault point is calculated according to the characteristic that the voltage along the transmission line is in linear monotone decreasing; and the imaginary part of the voltage drop from the relay location of the transmission line to the single-phase ground fault point is divided by the imaginary part of the voltage drop of the transmission line per unit length to obtain the fault location. The line single-phase ground fault single-terminal location method solves the problem that the transitional resistance and the load current influence the single-terminal fault location precision, is high in single-terminal location precision, simple in location principle and easy in program implementation, and does not need to adopt the search algorithm, so that direct calculation of the fault location is realized, location speed is quick and the real-time performance is strong.

The invention discloses a line single-phase earth fault single-terminal ranging method implemented by the aid of sequence components. The line single-phase earth fault single-terminal ranging method includes converting negative-sequence voltages of a power transmission line single-phase earth fault point into an equivalent zero-sequence voltage; accurately computing the fault distance according to a fault characteristic that a certain zero-sequence voltage of a power transmission line single-phase earth fault point is equal to the equivalent zero-sequence voltage so as to implement power transmission line single-phase earth fault single-terminal ranging. The line single-phase earth fault single-terminal ranging method has the advantages that the power transmission line single-phase earth fault single-terminal ranging is implemented according to distribution characteristics of the zero-sequence voltages along a power transmission line, influence of transition resistance on the ranging precision is eliminated in principle, influence of load currents and fault positions is prevented, and the ranging precision is high; a ranging principle of the method is simple, programs are easy to implement, the fault distance does not need to be directly computed by a search algorithm, and the method is high in ranging speed and instantaneity.

The invention discloses an electric transmission line phase fault single-ended distance measuring method. The electric transmission line phase fault single-ended distance measuring method includes the following steps of working out equivalent resistance through the voltage between fault phases, the current between the fault phases, and the negative-sequence current between the fault phases at the electric transmission line relay location, obtaining the voltage of a phase fault point through the fact that the equivalent resistance is multiplied by the negative-sequence current between the fault phases, working out the real part of a ratio between the voltage of the phase fault point and the voltage drop of an electric transmission line of per unit length, obtaining the additional fault distance caused by a transition resistor, and obtaining the fault distance from the electric transmission line relay location to the phase fault point through the difference between the real part of the ratio between the voltage between fault phases and the voltage drop of the electric transmission line of per unit length and the additional fault distance. The electric transmission line phase fault single-ended distance measuring method solves the problem that the transition resistor influences the precision of electric transmission line phase fault single-ended distance measuring, has high distance measuring precision and is simple in distance measuring principle. In addition, according to the electric transmission line phase fault single-ended distance measuring method, a program is easy to achieve, the fault distance is directly worked out without the need for application of search algorithms, distance measuring is fast, and the instantaneity is strong.

The invention discloses a method for realizing line interphase fault single-ended distance measurement by means of real part characteristics of voltage drop. According to the method, a voltage phase angle at an interphase short fault point is calculated by using fault interphase negative sequence voltage and positive sequence impedance of an electric transmission line per unit length, so that an additional fault distance generated due to transition resistance is calculated, and the fault distance from the electric transmission line protection installation position to the interphase short fault point is obtained by subtracting the additional fault distance generated due to transition resistance from the real part of a ratio of the fault interphase voltage to the voltage drop of the electric transmission line per unit length. The method solves the problem that the transition resistance and load current influence the accuracy of single-ended fault distance measurement; and when a high resistance short fault between phases of the electric transmission line happens, the method has high distance measurement accuracy, the distance measurement principle is simple, the procedure is easy to implement, the fault distance can be directly calculated without a search algorithm, the distance measurement speed is high, and the real-time performance is high.

The invention relates to a dynamic-real-time-parameter-based along-line voltage cross correction fault ranging method of a T type line. On the basis of electrical information of a T type line under the normal operating condition, real-time parameters of three-terminal lines are calculated dynamically in real time and calculation errors of the real-time parameters of the lines are corrected based on a genetic algorithm; after a fault occurs at one line, voltages of T nodes are calculated respectively based on a line distribution parameter line model under the modified parameters and a fault branch is determined by voltage comparison; two non-fault branches are equivalent to T terminals and form, together with one end of the fault branch, a two-terminal power transmission line model; and then two straight lines are formed by measuring voltages at two sides and calculating opposite-side voltages and an intersection point is calculated based on intersection of the straight lines, so that afault ranging method is formed. Therefore, the line parameter error can be adjusted dynamically in real time; the fault ranging precision is improved; and the engineering practicability is high.

The invention discloses an ultrasonic-based intelligent induction shower device, which relates to the field of induction shower devices; it includes a top spray shower and a top spray shower inlet pipe, the top spray shower includes an upper plate and a spray head, and the upper plate There is a cylinder between the nozzle and the nozzle, a sliding structure is fixed above the nozzle, and a spherical structure is arranged under the water inlet pipe of the top sprinkler. The structure is sleeved on the spherical structure, so that the sliding structure and the spherical structure form a ball twist connection, so that the nozzle can be rotated under the action of the cylinder; it also includes an induction device, which includes a single-chip microcomputer and an ultrasonic circuit, and the ultrasonic circuit It is electrically connected with the cylinder and the single-chip electromechanical; the invention solves the problem that the fixed design of the existing overhead shower device cannot adjust the spraying angle according to the position of the bather, and achieves the effect of real-time adjustment of the spraying angle of the overhead shower.

The invention discloses a method of achieving interphase short circuit fault distance measurement of a line by means of single-end electric quantities. The method includes measuring fault interphase voltage, fault interphase currents and fault interphase negative-sequence currents on a protective installation portion of a power transmission line, calculating an imaginary part of a ratio of the fault interphase voltage and the fault interphase negative-sequence currents, calculating an imaginary part of a ratio of voltage drop of the power transmission line per unit length and the fault interphase negative-sequence currents, dividing the imaginary part of the ratio of the voltage drop of the power transmission line per unit length and the fault interphase negative-sequence currents by the imaginary part of the ratio of the fault interphase voltage and the fault interphase negative-sequence currents, and obtaining a fault distance from the protective installation portion of the power transmission line to an interphase short circuit fault point. The method achieves precise measurement of the interphase short circuit fault distance of the power transmission line by means of the single-end electric quantities, and eliminates influences of transition resistance and load currents on measurement precision of the fault distance. Distance measuring principles are simple, programs are easy to achieve, operation amount is little, the distance measuring speed is high, and instantaneity is strong.