6results about How to "Reduce circulation loss" patented technology

The embodiment of the invention relates to the technical field of electric power, in particular to a converter control circuit, a converter and a charging pile. The converter control circuit and the converter comprise the coupling unit, the power conversion unit, the bus unit and the control unit, one path of input of alternating current is converted into two paths or multiple paths of output by additionally arranging the coupling unit, in the multiple paths of output, current is isolated and equally divided, and the output current of the power conversion unit is improved. Meanwhile, the internal structure of the coupling unit suppresses the circulating current in the converter, and the circulating current loss in the power conversion unit is reduced. Furthermore, the power conversion unit is provided with a plurality of T-shaped three-level inversion units, so that a multi-level technology is realized, multi-voltage level is provided, and multi-level output can remarkably reduce harmonic content of output voltage and current, reduce current ripples and improve electric energy quality.

The invention discloses a resonant dual-active bridge converter and a control method, and the converter comprises a primary full-bridge circuit, a secondary full-bridge or half-bridge circuit, a transformer, and an LC resonant network composed of a resonant inductor and a resonant capacitor which are connected in series. The control method comprises the following steps: acquiring parameters of an input voltage V1, an output voltage V2, a transmission power P, a transformer turn ratio N, a resonant inductance Lm and a resonant capacitance Cr of the converter; and calculating a primary fundamental wave equivalent voltage and a secondary fundamental wave equivalent voltage, and calculating an inner phase shift angle alpha between a first bridge arm and a second bridge arm in the primary full-bridge circuit through the primary fundamental wave equivalent voltage and the secondary fundamental wave equivalent voltage. The LLC converter has the beneficial effects that the inherent defects that the gain range of a traditional LLC converter is narrow (generally only 0.8-1.2) and the circulating current is sharply increased and the efficiency is sharply reduced when the voltage is seriously mismatched in the traditional phase-shifting DAB are fundamentally overcome.

The utility model discloses a wireless charging coil winding which comprises two or more layers of coils, the two or more layers of coils are stacked in the vertical direction, each coil comprises a first wire and a second wire which are arranged side by side in the horizontal direction, and the first wire and the second wire are wrapped with insulating layers. The first wire and the second wire surround multiple circles from outside to inside along the same axis from the same starting point, the first wire is located on the outermost circle, the first wire surrounds one circle more than the second wire, and inner ports are formed in the end, located on the inner circle, of the first wire and the end, located on the inner circle, of the second wire respectively; for two adjacent layers of coils, the front face of one coil right faces the back face of the other coil, the inner port of the first wire in one coil right faces the inner port of the second wire in the other coil, and the right-facing inner ports are electrically connected. The coil has the advantages of small coil resistance, small eddy-current loss, high efficiency, easy adjustment of coil inductance, low requirement on the inner diameter of the coil and the like.

The application relates to a built-in current-limiting reactor, which comprises an upper yoke, a coil and a lower yoke arranged in sequence from top to bottom, wherein the upper yoke is provided with an upper yoke frame, the upper side of the upper yoke frame is provided with an upper connecting seat, the inside of the upper yoke frame is provided with upper silicon steel sheets, the upper silicon steel sheets are insulated from the upper yoke frame and connected with the upper connecting seat, the upper connecting seat is connected with a corresponding upper clamp of a transformer, the lower yoke is provided with a lower yoke frame, the lower side of the lower yoke frame is provided with a foot pad, the inside of the lower yoke frame is provided with lower silicon steel sheets, the lower silicon steel sheets are insulated from the lower yoke frame and connected with the corresponding foot pad, the foot pad is connected with a corresponding lower clamp of the transformer, vertical screw rods are arranged between the upper yoke and the lower yoke, the upper ends of the vertical screw rods are fixedly connected with the corresponding upper connecting seats, the lower ends of the vertical screw rods are fixedly connected with the corresponding foot pads, upper lead wire rows and lower lead wire rows are arranged outside the coil, and the upper lead wire rows and the lower lead wire rows are respectively connected with corresponding low-voltage lead wire rows of the transformer. The built-in current-limiting reactor has lower cost, smaller loss, stronger short-circuit resistance, shortened production cycle and reduced installation space.

This application discloses a DAB converter and its driving control method. The method includes: obtaining the voltage transfer ratio based on the input voltage and output voltage of the DAB converter; obtaining the feedforward power based on the input voltage, voltage transfer ratio, and output current of the DAB converter; obtaining the primary-to-secondary side shift ratio based on the input voltage, output voltage, voltage transfer ratio, input current, and feedforward power of the DAB converter; obtaining the primary-side inward shift ratio and the secondary-side inward shift ratio based on the voltage transfer ratio, feedforward power, and the primary-to-secondary side shift ratio; and driving the DAB converter based on the primary-side inward shift ratio, the secondary-side inward shift ratio, and the primary-to-secondary side shift ratio. This invention optimizes the values ​​of the primary-side inward shift ratio, the secondary-side inward shift ratio, and the primary-to-secondary side shift ratio using relevant parameters of the DAB converter to achieve precise driving control of the DAB converter. By adjusting the control parameters of the DAB converter, the soft-switching range can be expanded, current stress reduced, and light-load efficiency improved, while significantly increasing the system's energy conversion rate.

The present invention discloses a three-phase transformer circuit and a transformer, wherein the circuit includes a phase a circuit, a phase b circuit and a phase c circuit including winding resistance and lead resistance, wherein the winding resistance includes resistance R3, resistance R4 and resistance R5, and the lead resistance includes resistance R2, resistance R6, resistance R1A, resistance R1B, resistance R1C and resistance R1D, wherein the resistance R1B leads the neutral point to ground from the middle; the three-phase circuit includes a connection circuit of phase resistances R0a, R0b and R0c; the three-phase circuit also includes a connection circuit of line resistances Rab, Rbc and Rac; the three-phase circuit is used to reduce the three-phase resistance unbalance rate. Through the technical solution provided by the present invention, the three-phase DC resistance unbalance rate of the transformer is reduced, the weight of the lead conductor is reduced, the transformer cost is reduced, the winding overvoltage and the circulating current generated between the winding phases are reduced, the circulating current loss between the windings is reduced, and the temperature rise of the windings is reduced, so as to achieve the effects of low noise, energy saving and consumption reduction and increase the life of the transformer.