172 results about "Susceptance" patented technology

The present invention refers to a circuit for current and voltage control in a switching power supply controlled on the primary side, comprising a transformer with a primary-sided and a secondary-sided main winding, wherein energy pulses are transmitted from the primary side to the secondary side. Furthermore, a primary-sided switch switches on an off a primary current through the primary-sided main winding. A primary current comparator determines a switch-off time of the switch depending on the primary current. In order to reduce the load dependency of the output voltage, the control variable is variably amplified by a feedback network and additionally the control variable is reduced depending on the output load through a correction network. To reduce noise generated by the energy-rich pulse transmissions at low frequencies and the waviness of the output voltage, the control variable is fed back to the primary current comparator so that the duration during which the primary current flows through the primary-sided main winding is reduced differently. To reduce the susceptance to failure when determining the switch-on time, a comparator voltage depending on the control variable is generated as reference.

Neural Network Loadflow (NNL) computation method is invented involving input vector composed of net nodal injection of real and reactive powers and diagonal elements of conductance and susceptance matrices multiplied by the squared voltage magnitude components of the flat-start normally used as initial solution estimate guess for loadflow solution by conventional NRL or SSDL methods. Training, and testing/validating input-output data sets are generated by applying uniform and non-uniform scaling factors applied to base case loads at PQ-nodes, resistance and reactance of transmission line branches. These scale factors are increased until loadflow solution by conventional methods such as Newton-Raphson Loadflow and Super Super Decoupled Loadflow methods diverge. Divergence of loadflow methods are due to node voltage, node angle, and numerical instabilities. Voltage magnitude and phase angle values in the solution before divergence are respective stability limits and voltage magnitude and phase angle values in loadflow solution provide direct measure to the respective stability margins. Also Suresh's diakoptiks based feature selection technique is presented for ANNs calculating one node variable with one neuron each in their output layers.

An RF coil assembly for an MRI system includes a resonator formed by a cylindrical shield and pairs of opposing conductive legs disposed symmetrically around a central axis and extending the axial length of the shield. Drive circuitry for each pair of opposing conductive legs includes a current balun that maintains substantially equal and opposite currents in the two conductive legs. Terminal susceptance elements are used to maintain maximum currents and minimum voltage at the midpoints of the conductive legs. Multinuclear measurements can be made simultaneously at different Larmor frequencies.

Three phase power flow analysis of an unbalanced power distribution system decouples voltage changes resulting from nodal admittance matrix into one contribution from a real part, conductance matrix, and other contribution from an imaginary part, and a susceptance matrix. A first voltage change and second voltage change resulting from conductance and susceptance matrices are determined respectively. The voltages of a node of the power distribution system are determined as a combination of first and second voltages.

A small multi-mode antenna in which a single feeding point can be used commonly for multiple frequencies and an RF module using such antenna for use in less-costly and small multimedia wireless apparatus is provided. The antenna is configured such that a single feeding point 4 which is common for multiple frequencies is set up at one end of a radiating conductor 1, a first one-port resonant circuit 2 is connected to the one end thereof, and a second one-port resonant circuit 3 is connected to the other end of the radiating conductor 1. With a conductance component of admittance in view from the feeding point 4 toward free space equaling the characteristic admittance in the RF circuit, a susceptance component of the admittance is canceled out by the resonant circuit 2 connected to the feeding point 4 for multiple frequencies.

A method for compensating dynamic three-phase unbalanced loadsand and its device characterizing in sampling values of line voltage and load line current of two sample points at the connecting place of the compensation device and the system to compute related sine signal basic wave symmetric component, then to calculate positive and negative sequential compensator threephase equal susceptance, thesum of which is the three-phase susceptance value for compensating load unbalance and providing reactive current for the load, the susceptance reference value to be converted to a control angle signal and an order of the thyristor switched capacitor to be sent to the pulse generation plate and the condenser zero-cross trigger plate for controlling two devices.

The invention relates to a center-feed ridge waveguide slot antenna. According to the center-feed ridge waveguide slot antenna, a slot array is formed on a ridged face of a ridge waveguide in a manner that two sides of a ridge are slotted in a staggering manner, and metallic tuning blocks are placed at the other side of the ridge opposite to slots, clung to the metallic ridge and a face of the waveguide, and used for adjusting the equivalent admittance of the radiation slots, so that the equivalent susceptance of the radiation slots is enabled to be zero, and the radiation slots are enabled to be in a resonant state; and the excitation of the waveguide adopts a center feeding manner so as to broaden bandwidth, and an excitation position is located on an un-ridged face of the ridge waveguide, so that conventional waveguide feeding manners, such as a coaxial probe bottom feeding manner, a waveguide center inclined slot back feeding manner and the like, can be adopted. According to the center-feed ridge waveguide slot antenna provided by the invention, a new form for a waveguide slot antenna is provided, and the low side-lobe can be realized; and the structure is compact, the feeding manner is simple, and the production is easy, so that the center-feed ridge waveguide slot antenna can serve as an arraying unit of a phased array antenna.

The invention discloses a parameter-estimation-based false data attach method of a modern power transmission network in a power system information security research field. On the basis of the traditional power system state estimation theory, an optimization model of a false data attack vector is constructed; and with an alternating direction method of multipliers (ADMA), the optimization model is solved. In order to solve problems of electrical parameter error existence, incomplete electrical parameters, and poor data in measuring data for an attacker, an unknown branch electrical susceptance is estimated by using a lagrangian multiplier method and an extended state estimation method. And then a false data attack vector is constructed based on the optimization model of the false data attack vector. According to the invention, flexibility and effectiveness of a false data attack are improved. The method also can be used for testing an effect of a false data attack defending method and verifying the capability of coping with the false data attack by the modern power transmission network.

The invention discloses an imbalance compensation and the ant colony optimization method for an SVC. The method is based on a variable structure to control the SVC, wherein, the variable structure control method comprises two aspects of the unbalanced load equalization compensation and the parameter control of a PI controller, wherein, the unbalanced load equalization compensation adopts the SVC compensation susceptance computational method which is based on the synchronous rotation reference coordinate transformation of a virtual symmetrical three-phase system; meanwhile, in the stabilization control of the system voltage, the ant colony algorithm optimization method is adopted to real time adjust and to optimize the parameter kp and ki of the PI controller. The invention ensures that the SVC can not only complete the unbalanced load equalization compensation but also control the stabilization, thereby raising the precision of the susceptance computation of the SVC, guaranteeing the balance compensation of the charge, improving the performance in the stabilization control of the SVC voltage and maintaining the voltage stabilization of a common connection joint. Therefore, the invention has high robustness and high response speed.

The invention discloses an antenna device. When the antenna device is arranged in an electronic device comprising a circuit board, the antenna device is used for receiving and transmitting wireless signals of the electronic device. The antenna device comprises a radiating body and an electric array susceptance component, wherein the radiating body comprises a first end which is grounded due to arrangement on the circuit board, the electric array susceptance component has a second end and a third end, the second end is connected with the radiating body, the third end is grounded due to arrangement on the circuit board, the electric array susceptance component has K kinds of different impedance values, and K is an integer greater than or equal to 2; when in a powered-on state, the radiating body can generate K kinds of resonance oscillation signals different in frequency range based on the K kinds of different impedance values.

The invention discloses an SVC composite control method based on rapid equivalent susceptance calculation, wherein, an SVC comprises a thyristor controlled reactor (TCR) and a passive filter bank. The SVC composite control method comprises the following steps: firstly, calculating the corresponding equivalent susceptance by using an equivalent susceptance computing method after detecting a voltage signal and a current signal; adding up an open-loop equivalent susceptance output value BLabc and a closed-loop PI regulator output value to obtain a total equivalent susceptance compensation value BTabc; calculating the actual input group number n of PPFs and the actual equivalent susceptance value of the TCR by a power divider according to the compensation value; and searching an Hash table by the TCR according to the actual equivalent susceptance value to obtain a corresponding triggering angle and then triggering opening of a corresponding thyristor to send out corresponding inductive reactive current for compensating capacitive reactive power and negative-sequence current, and finally realizing complete compensation of the reactive power and the negative-sequence current of a system. The SVC composite control method effectively reduces the calculated quantity of the system and improves the response time of the system.

Systems and methods for increasing recyclable material recovery from automobile shredder residue (4). Embodiments include separation of automobile shredder residue with a sorting system (5) such as an air sorting system, a non-ferrous automobile shredder residue air sorter, an air-locked automobile shredder residue sorting system, a non-magnetic magnetic sorter, a substantially isotropic quantization sorting system, an air-locked Z-box air classifier, low susceptance microparticle separator, a magnetic fuzz separator, a wind tunnel system, or the like perhaps with substantially horizontal laminar air flow (7) and can be used with or without out other traditional automobile shredder residue sorting systems (16) or (15) perhaps creating additional recyclable quantities and even better separated results such as with zorba and zurik and the like.

A first antenna element is embodied in a blanched structure, and a second antenna element is embodied in a blanched structure. A low coupling circuit for increasing susceptance with an increase in frequency is interposed between the first antenna element and the second antenna element. The first antenna element and the second antenna element exhibit resonance of a Y12 component of an admittance matrix between first and second frequencies and between second and third frequencies. The first branch element and the third branch element assume a value of nearly a quarter of a resonant electrical length of the Y12 component of the admittance matrix between the first and second frequencies. The second branch element and the fourth branch element assume a value of nearly a quarter of the resonant electrical length of the Y12 component of the admittance matrix between the second and third frequencies.

The invention relates to an automatic tuning method of a preset arc suppression coil, which comprises the following steps: further calculating the off tuning degree and the damping ratio of a power grid through measuring the change on the unbalanced voltage of the power grid; measuring the unbalanced voltage at the neutral point of the power grid and a certain line voltage value of the power grid during the normal operation of the power grid, calculating and monitoring the change on the relative unbalance degree of the power grid to judge whether the off tuning degree of the power grid is changed, i.e. whether the power grid requires line delivering and switching operations, and deciding whether the off tuning degree and the damping ratio of the power grid are newly measured; when the off tuning degree and the damping ratio of the power grid are measured, firstly measuring the unbalanced voltages of the power grid, then, controlling a tuned arc suppression coil to increase and output compensating current (electrical susceptance) for the power grid by a controller, and finally, measuring the unbalanced voltage of the power grid and calculating the off tuning current and the damping ratio of the power grid. The arc suppression coil is adjusted according to the measured off tuning current of the power grid to output the compensating current and then the currently running off tuning current of the power grid is further calculated again so as to validate that the currently running tuning current of the power grid is smaller than the setting valve of the off tuning current.

The invention discloses an iteration frequency domain minimum mean square error equilibrium method under a double-dispersion channel based on weighted score Fourier transformation, and relates to an iteration frequency domain minimum mean square error channel equilibrium method in a mixed carrier wave communication system under a wireless double-dispersion channel or an underwater acoustic susceptance channel, in order to solve the problem of energy dispersion of signals on a time domain or a frequency domain at the same time. The method comprises the following steps that: firstly, a mixed carrier wave modulation system emitting end completes the mixed carrier wave modulation; secondly, a cyclic prefix is added for a time domain sequence x and is subjected to parallel-serial conversion; thirdly, a time domain sampling sequence is transmitted in serial; fourthly, the mixed carrier wave modulation system receiving end neglects a CP (computer program) part; fifthly, the time domain sampling sequence y is subjected to DFT (discrete Fourier transformation) at N points; sixthly, sampling points at the frequency corresponding to a certain sub carrier wave of the frequency domain are subjected to linear MMSE (minimum mean square error) estimation and N-point-stage WFRFT (weighted score Fourier transformation); seventhly, apriori information and Rho s=X(s, s) are estimated gradually; eighthly, the apriori information of the corresponding frequency domain is calculated; ninthly, the apriori information is fed back. The iteration frequency domain minimum mean square error equilibrium method under the double-dispersion channel based on weighted score Fourier transformation provided by the invention is applied to the mobile communication field.

The invention discloses an online identification method of small-disturbance stability parameters based on PMU measurement data. The method includes: according to a linearization state matrix, with the combination of the PMU measurement data (generator angular velocity, power angle and internal potential trend data) of an electric power system, the matrix operation form of the ordinary least squares solution of to-be-estimated parameters (conductance, susceptance, and generator time constant and damping coefficient) is deduced. The beneficial effects of the method are that the current operation state can be accurately reflected through abundant measurement data, and a great help is provided for the improvement of the accuracy of practical parameters of the electric power system.

The invention relates to multiview-based underwater target classification system and method. The method is based on a mode recognition system the input data of which is multiview data obtained by radiating a target object from multiple angles; the method comprises the following steps: data acquisition and preprocessing: receiving and preprocessing the input multiview data; feature extraction: carrying out feature extraction on the preprocessed multiview data by adopting a feature algorithm suitable for multiview data; classifier designing: designing a classifier by adopting a hidden Markov model (HMM); classification judgment: judging the classifier to which the feature extracted from the multiview data is input, thus obtaining a classification result. By utilizing the method, through a plurality of acoustic susceptance and a plurality of information sources, multi-dimensional space data acquisition is carried out as feature extraction information sources in the underwater target classification system, the number of target feature vector dimensions is increased, and the information reliability can be improved.

A method, system, and software for predicting a brownout or blackout in a smart power grid network. A network vulnerability characterization is selected among line susceptance, modified line susceptance, power traffic, and power loss. The selected characterization is analyzed based on a calculation matrix such as a pseudo-degree matrix, pseudo-Laplacian matrix, or a pseudo-adjacency matrix. A centrality score, such as degree centrality or eigenvector centrality, is determined for at least one bus in the network based on the selected network vulnerability characterization and the corresponding calculation matrix. A series of network simulations are performed based on removal of at least one bus in the network. The network simulations are specific to the selected vulnerability characterization and corresponding calculation matrix.

The invention discloses an amplitude phase error self-correcting method applicable to a uniform circular array acoustic susceptance system and belongs to the technical field of signal processing in the acoustic susceptance system. Firstly, a uniform circular array is converted into a virtual line array through a mode-space conversion theory; then, direction-of-arrival estimation is carried out on the uniform circular array converted into the virtual line array through a TSI algorithm, and an azimuth angle of a correction source is determined; then the amplitude phase error parameter of the uniform circular array is estimated through a spatial filter. The azimuth angle of the correction source is estimated by the adoption of the TSI algorithm under the condition that the position of the correction source is unknown, higher azimuth angle estimation precision is achieved, and then higher amplitude phase error estimation precision is achieved.

The invention discloses an accurate fault locating method for double circuit lines on the same pole, which is used for solving the problems of locating errors caused by unavailability of avoiding mutual impedance and mutual susceptance phase difference among leads and the realization of fault location in any fault existing in the conventional fault locating method for double circuit lines on the same pole. According to the accurate fault locating method, an accurate fault calculation method is adopted. The accurate fault locating method comprises the following steps of: 1, calculating measured values of current and voltage vectors before and after a fault with a Fourier algorithm; 2, calculating impedance matrixes and potentials of systems on both sides; 3, calculating to obtain a transfer matrix ranging from fault points of the double circuit lines on the same pole to a bus by using different fault distance values with a feature modulus decomposition method; 4, constructing a resistance matrix of the fault points by using different fault resistance values; 5, solving an equation to obtain calculated values of voltage vectors of buses on both sides and current vectors from a circuit to a bus; and 6, calculating an error quadratic sum of each vector calculated value and measured value. In different values of a fault distance and fault resistance, the error quadratic sum calculated by using a fault distance and a fault resistance value which are most proximate to a practical fault distance and practical fault resistance in the step 6 is least.

A method and an apparatus for detecting a phase-to-earth fault on a three-phase electric line of an electric network, the apparatus determining a neutral admittance based on a ratio of a difference between zero sequence currents on the three-phase electric line and a difference between zero sequence voltages in the electric network before an earth fault and during the earth fault. The apparatus also compares the determined neutral admittance, to a predetermined operation characteristic to detect a phase-to-earth fault on the three-phase electric line. The predetermined operation characteristic, when presented on an admittance plane, defines a closed area such that the center of the closed area is offset from the origin of the admittance plane towards a negative susceptance direction and/or towards a negative conductance direction.