4results about How to "Reduce switch stress" patented technology

The invention relates to the technical field of power electronic direct-current converters, in particular to an input and output common-ground high-gain boost converter which comprises a direct-current voltage source Vin, diode components D0-D4, capacitor components C0-C4, a first coupling inductor L1, a second coupling inductor L2, a first mosfet tube S1, a second mosfet tube S2 and a resistor R. The two main loops operate in a staggered mode, so that input current is continuous, input current ripples are small, relatively stable energy is continuously provided for the circuit, the voltage multiplication unit is adopted, the amplification factor of the circuit is increased, the duty ratio of the mosfet tubes S1 and S2 is adjusted, and small current ripples can be kept even under the condition that the boost factor is large. The device has the advantages of high step-up ratio, low device stress, high efficiency, easiness in control and implementation, lower cost and the like, and is suitable for a new energy power generation scene needing high direct current bus voltage grid-connected output under a low input voltage condition.

The invention provides a resonant converter, a transformer comprises a primary side winding and two secondary side windings, a resonant circuit comprises two first switches which are connected in series, a rectifying circuit comprises two second switches which are connected in series and an output end, and the output end is connected to a connection point between the two secondary side windings. The sensing circuit senses at least one of the voltage and the current of the output end, and provides a plurality of switch control signals to the two first switches and the two second switches according to the at least one of the voltage and the current. The controller correspondingly sets the starting frequency of the switch control signals and at least one of the voltage and the current of the output end to be in a reverse relation, controls the switch control signals to drop from the starting frequency, and controls the time sequence deviation between the switch control signals to drop, so that the voltage of the output end reaches a default voltage value.

The invention discloses a mirror image high-gain Boost converter with switch tubes synchronously switched on and switched off, and belongs to the technical field of power electronic direct current conversion. The converter comprises a direct-current voltage source, two inductors, seven capacitors, seven diodes and two MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor) switching tubes. The core innovation lies in that the two switching tubes are completely and synchronously switched on and switched off, no dead time needs to be set, and the control logic is simplified. Through specific connection and multiplexing of a capacitor and an inductor, an efficient voltage-multiplying unit is formed, extremely high voltage gain is achieved, the gain formula is shown in the specification, and D is the duty ratio of a switching tube. According to the structure, high gain is obtained, meanwhile, the voltage stress of the switching tube is remarkably reduced, the value of the voltage stress is only output voltage, and the switching loss is effectively reduced. The device has the advantages of being small in number of devices, compact in structure, high in efficiency, low in cost and the like, and is particularly suitable for occasions where low input voltage needs to be boosted to high direct current bus voltage in the new energy field of photovoltaic systems, energy storage systems and the like.

The application discloses a switching control method based on SPWM soft starting and a pulse type load LLC resonant converter. k The converter mainly comprises an LLC resonant converter, an H-bridge inverter circuit and a load thereof, and the control method is as follows: k For any positive integer, the load state is accurately judged through an H-bridge switching logic unit, and burst intermittent control and linear frequency control are respectively adopted in the no-load state and the full-load state in the steady state; when the load is switched, two-pulse optimal control is carried out by using a nonlinear SOTC optimal trajectory controller, so that the state is transitioned to a new mode along the shortest trajectory, and a dynamic response optimizer is introduced to compensate the frequency after switching according to the state radius error, so as to suppress voltage secondary fluctuation, solve the problems of slow dynamic response and large output voltage fluctuation of a traditional linear control facing the pulse type load LLC resonant converter, and improve the output voltage stability and anti-interference ability of the system.