16 results about "Magnetic inductance" patented technology

The application relates to the technical field of power electronic converter control, and provides a three-port flyback DC-AC converter, characterized in that the three-port flyback DC-AC converter comprises a flyback circuit, a power frequency reverse bridge, an AC-DC converter and a CL filter which are sequentially connected in cascade; the AC-DC converter is an AC-DC three-winding flyback converter which can realize power factor correction function, and is realized through active device multiplexing and magnetic component multiplexing, and comprises a flyback transformer T 2, excitation inductance L f , output switch Q 3, Q 4; the modulation method is to calculate instantaneous output power P o , judge the operation mode of the system, and respectively perform active modulation, reactive modulation or mixed modulation, so that the power factor is adjusted through the modulation method.

The application discloses a resonant converter and a control method. The resonant converter comprises a primary side inverter switching circuit (II), a primary side resonant cavity (III), a transformer (IV), a secondary side rectifier circuit (V) and a filter output circuit (VI) connected in sequence. The primary side resonant cavity (III) comprises a resonant capacitor, a resonant inductor, an excitation inductor and two switch tubes connected in reverse series. The secondary side rectifier circuit (V) comprises two power tubes and two switch tubes. In the control, when the resonant converter outputs a low voltage, a PWM control is adopted to adjust the output voltage; when the resonant converter outputs a high voltage, a phase shift control is adopted to adjust the output voltage. The resonant converter can adjust the output voltage from a low voltage to a high voltage, and the voltage adjustment range is wide. Compared with the traditional technology, the frequency adjustment range is obviously reduced, the optimization design of magnetic devices such as transformers and inductors is facilitated, and the power density and efficiency of the resonant converter are improved.

According to the low-cost high-magnetic-conductivity high-magnetic-shielding magnetically soft alloy and the preparation method thereof, Fe-Si-Al is adopted as a basic system, microalloying elements such as B and Nb are creatively introduced, specific critical cold rolling and magnetic field heat treatment processes are adopted, and the obtained magnetically soft alloy has high magnetic conductivity and high magnetic shielding effectiveness. Wherein the resistivity of the alloy is effectively improved and the magnetocrystalline anisotropy is optimized through the synergistic effect of Si and Al; the grain boundary segregation effect of the B element purifies the grain boundary, and the moving resistance of the magnetic domain wall is remarkably reduced; and the dispersed precipitated phase formed by the Nb element effectively refines the initial crystal grains and lays a foundation for subsequent formation of uniform and thick recrystallized crystal grains. Particularly, a strong Gaussian texture is induced through accurately controlled critical cold rolling deformation, and magnetic domains are directionally arranged in an easy magnetization direction in combination with magnetic field heat treatment applied near a Curie point, so that the coercive force is fundamentally reduced, and the initial magnetic conductivity is improved.

A conversion device comprises: a transformer for generating an output voltage according to an input voltage; the current transformer is coupled to the first node of the transformer; one end of the resonant inductor is used for receiving the input voltage, and the other end of the resonant inductor is coupled to the current transformer at a second node; and the excitation inductor is coupled to the transformer at the third node, the excitation inductor is coupled to the resonant inductor at the second node and is adjacent to the resonant inductor, and the current transformer is arranged between the transformer and the resonant inductor along the first direction. According to the conversion device disclosed by the utility model, the occupied space on the printed wiring board is effectively reduced, and the magnetic flux generated by the resonant inductor and the excitation inductor to the transformer together is reduced. The disclosure also relates to a related manufacturing method.

This invention relates to a design method for a magnetically integrated planar transformer with customized leakage inductance, comprising the following steps: S0 obtaining the target magnetizing inductance and the target leakage inductance; S1 calculating the required core air gap length to achieve the target magnetizing inductance; S2 obtaining the maximum leakage inductance L within the core window without an air gap through finite element simulation. lk0_max And the maximum leakage inductance L after opening an air gap of the stated length lk_max Then the correction coefficient k is calculated. gap S3 is based on the target leakage sensing and leakage sensing L. lk_max The optimal winding arrangement that matches the target leakage inductance is obtained by selecting a winding arrangement with smaller parasitic capacitance or by traversing all winding arrangements. This invention enables a low-cost, small-volume, and simple-layout magnetically integrated planar transformer.

The invention provides a parameter identification method and device for an induction motor, electronic equipment and a storage medium, and relates to the technical field of induction motors, and the method comprises the steps: setting the d-axis current of the induction motor as direct current and the q-axis current as zero under the condition that the induction motor is in a no-load rotation state, identifying stator self-inductance and stator resistance of the induction motor according to a first voltage signal generated by the induction motor; under the condition that the induction motor is in a static state, d-axis current is set to be alternating current and q-axis current is set to be zero, and the total resistance and the total leakage inductance of the induction motor are identified according to a second voltage signal generated by the induction motor; wherein the angular frequency of the alternating current is equal to the preset high-frequency angular frequency; and respectively identifying rotor resistance and excitation inductance of the induction motor based on the total resistance, the stator resistance, the stator self inductance and the total leakage inductance. According to the method, the problem of complicated calculation caused by multi-parameter joint solution in a single identification environment can be effectively solved, so that automation and engineering application can be realized.

The application relates to a magnetic capacity element, and relates to the design of the magnetic capacity element from the definition, calculation formula and port characteristics of the element. The strength of the magnetic hysteresis phenomenon in the vector magnetic circuit can be predicted and controlled from the magnetic circuit angle by adding or reducing the magnetic capacity element in the magnetic circuit, the effect caused by the magnetic hysteresis phenomenon is controlled, the magnetic flux vector state in the magnetic circuit is consistent with the target magnetic flux vector state, and an application method is provided based on the same. The target magnetic circuit is composed of the magnetic capacity element, the magnetic resistance element and the magnetic inductance element in series, three physical phenomena of the magnetic resistance, the eddy current and the magnetic hysteresis in the magnetic circuit are quantitatively characterized by the magnetic circuit parameters corresponding to the three magnetic circuit elements, and the operating characteristics of the magnetic circuit can be changed in a targeted manner and the vector magnetic quantity and the magnetic circuit power in the magnetic circuit can be changed in a purposeful manner according to the change of different magnetic circuit parameters.

This invention discloses an LLC resonant converter, comprising an inverter circuit, an LLC resonant cavity, a transformer, a rectifier network, and a filter output circuit connected sequentially from input to output. The LLC resonant cavity includes a resonant inductor Lr, a magnetizing inductor Lm, a resonant capacitor Cr, a switching transistor S5, a switching transistor S6, and a clamping resonant capacitor Cs. One end of the resonant capacitor Cr is connected to the inverter circuit, and the other end of the resonant capacitor Cr is connected to one end of the resonant inductor Lr and the drain of the switching transistor S5. The other end of the resonant inductor Lr is connected to one end of the magnetizing inductor Lm and one end of the primary winding Np of the transformer T. The other end of the magnetizing inductor Lm is connected to the other end of the primary winding Np of the transformer T, the drain of the switching transistor S6, and the inverter circuit. The source of the switching transistor S6 is connected to one end of the capacitor Cs, and the other end of the capacitor Cs is connected to the source of the switching transistor S5. This invention solves the problem of non-monotonic output voltage gain caused by the resonance of the resonant inductor Lr and the parasitic capacitance of the transformer during the clamping process in PWM mode.

This invention provides a method, apparatus, electronic device, and dielectric for determining the resonant parameters of a DC-DC converter, relating to the field of power electronics technology. The method includes: determining the initial electrical parameters of the power switching devices in the DC-DC converter based on preset electrical parameters; determining the initial resonant inductance value of the resonant network in the DC-DC converter based on the initial electrical parameters and preset electrical parameters; determining the optimized magnetizing inductance value corresponding to the resonant network based on the initial electrical parameters and the high-frequency resonant phase angle during the dead time; ensuring the optimized magnetizing inductance value satisfies the zero-voltage turn-on condition; and determining the target resonant parameters in the DC-DC converter that satisfy the target voltage gain based on the optimized magnetizing inductance value and the initial resonant inductance value. This invention optimizes the parameter range of the magnetizing inductance based on the coupling relationship between the magnetizing inductance and the high-frequency resonant phase angle during the dead time, ensuring that the optimized magnetizing inductance value of the resonant network can satisfy the zero-voltage turn-on condition.

The invention provides a direct current-direct current system based on a bidirectional switch and a modulation method thereof. The system comprises an input side voltage dividing filter capacitor circuit, a resonant inductor, a diode follow current circuit, the bidirectional switch, a half-bridge switch circuit, a resonant capacitor, an excitation inductor, a high-frequency transformer, an uncontrolled rectifier module, an output side filter capacitor and a load resistor. According to the modulation method of the system, energy stored by the resonant inductor Boost is changed by adjusting the duty ratio of the two-way switch at a fixed frequency, so that the output voltage of the DC-DC system is adjusted. According to the invention, high-efficiency fixed-frequency boost output of a DC-DC system can be realized, especially, soft switching of semiconductor devices can be realized, the loss is low, and the system structure and the modulation method are simple and easy to realize.

The present invention belongs to the technical field of motor control. Specifically disclosed are an electromagnetic torque equation, maximum torque per ampere calculation method and control method for a motor and based on a vector magnetic circuit. First, a vector magnetic circuit model for a permanent magnet motor is established; an equivalent magnetic inductance is used to characterize the influence of eddy current and hysteresis effects in a magnetic material on the electromagnetic torque of the motor; an electromagnetic torque equation for the permanent magnet motor and based on a vector magnetic circuit, which equation contains the equivalent magnetic inductance, is established by means of coordinate transformation; and then a maximum torque per ampere control method for the permanent magnet motor is further provided. The methods provided in the present invention take into full consideration the influence of eddy current and hysteresis effects in the magnetic material on the electromagnetic torque of the motor, and the provided maximum torque per ampere control makes the torque control of the permanent magnet motor more accurate.

The application discloses a virtual magnetic core transformer with a composite magnetic induction loop and a magnetic circuit parameter configuration method thereof, and belongs to the technical field of power generation, power transformation or power distribution. Based on the assumption that each composite magnetic induction winding is a concentrated winding, a generalized magnetic impedance matrix representing the coupling relationship of each loop is constructed, a condition equation with a zero real part of a matrix determinant is established, and a general analytical solution of a compensation capacitor is solved. Furthermore, a plurality of composite magnetic induction branches are set as a symmetrical structure with the maximum main magnetic flux as the target, and the simplified analytical solution of the compensation capacitor value adjusting with the branch number is obtained under the condition of ignoring the branch parasitic resistance, so that a direct basis is provided for the design and parameter selection of the transformer. The application directly reveals the magnetic resistance compensation mechanism, avoids complex circuit equivalent transformation, effectively suppresses the primary excitation current, disperses the thermal stress of the composite magnetic induction loop, widens the effective magnetic impedance bandwidth, and reconstructs the low magnetic resistance characteristic of the transformer under the premise of no magnetic core.

This invention relates to a method for optimizing the resonant cavity parameters of an LLC circuit for a bidirectional DC-DC converter for energy storage. The method includes: selecting N resonant inductance values ​​and calculating the corresponding magnetizing inductance and resonant capacitance values; calculating the corresponding resonant inductance current, magnetizing inductance current, and resonant capacitor voltage; designing the resonant inductance, magnetizing inductance, and resonant capacitor separately, and calculating feasibility labels, costs, and losses; integrating the inductance and capacitor design data into an input dataset; using the comprehensive index calculated using cost and losses as the first output dataset; using the feasibility labels as the second output dataset; and calculating the maximum mutual information coefficient between each input data feature and each output dataset to form the final input dataset and the final output dataset. These datasets are then input into an SVM for training. Randomly generated input data is then input into the SVM for output. After eliminating infeasible solutions, the optimal design scheme is selected. This method is beneficial for improving the performance and efficiency of resonant cavity parameter optimization design.

The embodiment of the invention discloses a bidirectional full-bridge LLC resonant circuit and a power flow direction self-switching method, the bidirectional full-bridge LLC resonant circuit adopts a full-bridge structure in which an input side and an output side are completely symmetrical, consists of eight MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor) switching tubes, and is matched with a transformer excitation inductor through an equivalent resonant inductor-capacitor unit to form a bidirectional resonant cavity. According to the control method, switching frequency is dynamically adjusted based on real-time load voltage detection, when the voltage drops, frequency is reduced, gain is increased, and when the voltage rises, the frequency is increased until input current returns to zero; and if the current is zero and the voltage is still higher than the target value, automatically switching to a reverse charging mode, otherwise, recovering forward power supply. According to the design, seamless conversion of a charging mode and a discharging mode is achieved through a zero-current triggering mechanism, the soft switching characteristic and efficient energy transmission of the LLC circuit are maintained in a wide load range, and the dynamic response capability and the system integration degree of equipment such as a new energy vehicle and an unmanned aerial vehicle are remarkably improved by combining fixed duty ratio driving and dead zone control.

A high-frequency three-port DC-DC converter with zero-voltage switching operation comprises an input voltage source Vbat, an output voltage source VH, a first voltage source Vin, a first capacitor C1P, a second capacitor C2P, a third capacitor C3, a fourth capacitor C1S, a fifth capacitor C2S, a first stray capacitor CS1P, a second stray capacitor CS2P, a third stray capacitor CS1S, a fourth stray capacitor CS2S, a first inductor L1, a second inductor L2 and an excitation inductor Lm. The circuit comprises a first power switch tube S1P, a second power switch tube S2P and a third power switch tube S1S, in the mode 1, the first stray capacitor CS1P is discharged, and the second stray capacitor CS2P is charged; in the mode 2, the first switch tube S1P and the third switch tube S1S apply pulses and are turned on in the ZVS state; in the mode 3, the first stray capacitor CS1P is discharged, and the second stray capacitor CS2P is charged; in the mode 4, the second switch tube S2P and the fourth switch tube S2S are conducted to the ZVS state at the moment t3; the utility model has the characteristics of small volume, simple switching mode, high efficiency and high power density.