43results about How to "Reduce voltage and current stress" patented technology

The invention discloses a method for eliminating the cross-coupling coefficient of a multi-transmission-multi-pick-up-multi-load IPT system. The method includes determining the resonance compensation circuits on the primary side and the secondary side; determining all circuit parameters satisfying the system output performance index; Current equation; determine each cross-coupling coefficient existing in the circuit, and solve the current equation of each branch; make the difference of each branch current equation without considering the cross-coupling coefficient and considering the condition of the cross-coupling coefficient, and obtain the difference equation of each branch current ; Add the compensation impedance where there is a cross-coupling coefficient in the difference equation; bring the solved current equation of each branch into the difference equation containing the impedance to be compensated, and solve it in reverse to obtain the impedance value to be compensated for each branch; The circuit angle eliminates the cross-coupling coefficient between multiple coils, and is universal to any multi-transmission-picked-multi-load IPT system, which is beneficial to the guidance of the elimination of the cross-coupling coefficient of the actual system and improves the system output performance.

The invention discloses a parallel resonant zero-voltage switch push-pull forward converter. The main circuit of the converter includes a primary circuit and a secondary circuit; the primary circuit is provided with a resonant inductor and a parallel resonant capacitor. Through the resonance of the resonant inductance and the parallel resonant capacitor, the zero-voltage switch of the main power transistor in the primary side circuit is realized. The converter can eliminate the voltage peak of the main power tube, improve the EMC effect, increase the boosting capability and conversion efficiency. The circuit of the invention has the advantages of simple structure, convenient control and reliable operation.

The invention discloses an interleaved parallel LED drive circuit based on a quadratic Buck and its working method, belonging to the field of power electronics, including an AC input, a rectifier bridge D1, a filter inductor Lf, a filter capacitor Cf, and two switch tubes Q1 and Q2 , diodes D2, D3, D4, D5, D6, inductors L1, L2, L3 and energy storage capacitors C1, C2, output capacitor Co and LED load. Based on the existing secondary buck converter circuit topology, a switch network composed of switch tube Q2, inductor L3, capacitor C2 and diode D6 is added to form an interleaved parallel structure, which effectively reduces the output current ripple and reduces The filter inductor design reduces the volume of the converter, improves system stability and power density, and realizes high efficiency and high power factor operation.

The invention discloses a lithium battery system with a self-repair function and a self-repair method thereof, which belong to the field of battery fault repair. The lithium battery system includes a bidirectional DC-DC converter, a supercapacitor group, a processor, a battery detection module, and multiple A battery pack composed of lithium batteries and multiple switches. The super capacitor pack is used to provide power for the bidirectional DC-DC converter; the battery detection module is used to detect the status data of each lithium battery in the battery pack; the status data is fault or Normal; when the status data is faulty, the processor controls the on and off of multiple switches in the battery pack to make the bidirectional DC-DC converter replace the faulty lithium battery. When a faulty lithium battery occurs in the system, the external power supply of the system is abnormal, and the self-repair function refers to that the system can automatically repair the abnormal external power supply. The present invention replaces the faulty lithium battery with a bidirectional DC-DC converter after detecting the faulty lithium battery, so that the system The external power supply returns to normal, with self-repair function.

The invention belongs to the technical field of circuit control, in particular to a SiC MOSFET open-loop active drive circuit. The circuit includes a traditional drive circuit, and also includes an auxiliary circuit, the auxiliary circuit includes a di / dt detection circuit and a shunt circuit; the di / dt detection circuit is used to judge the turn-on and turn-off phases of the SiC MOSFET, and judge the obtained The signal is transmitted to the shunt circuit; the shunt circuit shunts the gate current of the SiC MOSFET through the signal of the di / dt detection circuit. The present invention provides a SiC MOSFET open-loop active drive circuit, which adds a shunt circuit and a di / dt detection circuit after the traditional SiC MOSFET drive circuit, shortens the switching delay time, reduces the switching loss, and the active drive circuit is Open-loop operation reduces system cost and complexity.

The invention discloses an asymmetrical half-bridge zero-voltage soft switching inverter type welding and cutting machine, which comprises an input filtering circuit, a primary side rectifier filtering circuit, an asymmetrical half-bridge soft switching inverter circuit, an isolation transformer circuit, a secondary side rectifier filtering circuit and a master control board circuit, wherein the asymmetrical half-bridge soft switching inverter circuit comprises a main inverter circuit half-bridge consisting of a first insulated gate field effect power switch device and a second insulated gatefield effect power switch device, as well as a first driving resistor, a second driving resistor, a first resonant capacitor, a second resonant capacitor, a saturated inductor and a stopping condenser; the central point of a bridge arm of the main inverter circuit is connected with an intermediate-frequency transformer through the stopping condenser; the saturated inductor, the first and the second resonant capacitors and a leakage inductor of the intermediate-frequency transformer form a soft switching resonant circuit. The asymmetrical half-bridge zero-voltage soft switching inverter type welding and cutting machine is simple in structure and low in implementation cost, and the switching voltage stress and current stress are reduced considerably.

The invention belongs to the field of electric energy transmission, and discloses a maximum efficiency tracking DC-DC converter and its control method for inductive electric energy transmission systems, including LCL-S compensation topology, uncontrolled rectifier bridge and double-tube Buck-Boost circuit; LCL The output of the ‑S compensation topology is connected to the input of the uncontrolled rectifier bridge, and the output of the uncontrolled rectifier bridge is connected to the input of the dual-tube Buck‑Boost circuit. The present invention realizes the constant voltage control of induction electric energy transmission by adjusting the phase shift angle between the leading and lagging bridge arms of the full-bridge inverter circuit, and realizes impedance matching by controlling the DSBB switch tube by adopting an interleaved duty cycle bias modulation strategy. Keep the equivalent load on the output side of the rectifier bridge always at the maximum efficiency load point; the double-tube structure of the present invention can effectively reduce the voltage and current stress of the switch tube, so that the system output has a wider voltage range and a higher power level; The adjustment of the pressure mode can make the load adjustable range wider when the system realizes the maximum efficiency tracking, which greatly improves the applicability of the system.

The invention discloses a wireless energy dynamic constant power output system and its equivalent resistance control method, and relates to the technical field of wireless energy dynamic transmission. The invention includes a sending end and a receiving end, the sending end includes a sending coil Lp, and the receiving end includes a load Secondary side assembly 1 and secondary side assembly 2 connected by R, secondary side assembly 1 includes receiving coil Ls1 parallel to sending coil Lp, secondary side assembly 2 includes receiving coil Ls2 parallel to sending coil Lp, receiving coil Ls1 and receiving coil Ls2 They are composed of square coils with a side length of L, the transmitting coil Lp is composed of several square coils with a side length of L in cascade, the receiving coil Ls1 and the receiving coil Ls2 are overlapped to form a secondary coil group, and the length of the overlapping part is L / 2. The invention ensures that the total power is evenly distributed between the receiving end of the secondary side assembly 1 and the receiving end of the secondary side assembly 2 during the moving process, which not only reduces the voltage and current stress of the switch tube, but also ensures the output power of the system constant.