4results about How to "Prevent magnetic saturation" patented technology

The utility model relates to a kind of power converter and power grid power supply system, the power converter includes: bus capacitor module, with equalization midpoint;Multi-phase input circuit is used to access multi-phase power supply, each phase input circuit includes boost inductor and bidirectional switching switch, boost inductor, bidirectional switching switch and equalization midpoint are sequentially connected;Bridge module includes multiple conversion bridge arms, the upper end and the lower end of multiple conversion bridge arms are connected with the positive terminal and the negative terminal of bus capacitor module one-to-one correspondence respectively, the midpoint of multiple conversion bridge arms and the common connection end of boost inductor and bidirectional switching switch in multi-phase input circuit are interconnected one-to-one correspondence;Each phase input circuit further includes filter inductor and filter capacitor, one end of filter inductor is connected with the common connection end of corresponding phase, the other end of filter inductor is connected with the neutral point of multi-phase power supply through the filter capacitor of corresponding phase, and each phase filter inductor is coupled with the boost inductor of corresponding phase and is set up.

The invention discloses an auxiliary power module (APM) with a lithium battery equalization function and a control method thereof, and belongs to the field of DC-DC converters, the APM comprises a high-voltage side, n half-full bridge type converters, a filter capacitor C and a low-voltage side, and the high-voltage side comprises 2n lithium battery units; and the low-voltage side comprises a 12V low-voltage storage battery BLV. Aiming at the problem of high cost of the existing active equalizer, the active equalization function of the lithium battery is integrated in the APM, and the control method comprises the following steps of: balancing adjacent battery units on a high-voltage side and simultaneously solving the problem of magnetic saturation of a transformer by using an asymmetric duty ratio modulation strategy; two-way flow of energy between the high-voltage side and the low-voltage side is achieved through a phase shift control strategy, four different operation modes are achieved through the control method, and the market competitiveness of the product is effectively improved.

The invention relates to the field of power electronics, and particularly discloses an input-parallel output-series dual-active bridge switching tube open-circuit fault-tolerant control method, which comprises the following steps: fault detection: identifying the position of an open-circuit fault switching tube; fault-tolerant control is carried out, specifically, current bias is corrected by adopting strategies of reducing the duty ratio of a secondary side and increasing D3 or blocking a switching tube of the same bridge arm and increasing D1 for a primary side fault or a secondary side fault; adaptive voltage-sharing control is carried out, voltage reference values are dynamically generated in three stages of starting, stabilizing and tracking based on operation time and voltage states, control modes and parameters are switched in the tracking stage according to fault and imbalance conditions, and voltage balance among modules under all working conditions is realized; and carrying out change rate limitation and hard amplitude limiting on the voltage reference value. According to the method, current bias caused by faults can be effectively eliminated, current stress is reduced, and voltage balance and stability of the multi-module DAB system during switch tube open-circuit fault decline operation are ensured.

The invention provides a multilayer combined magnetic pole type permanent magnet motor, and belongs to the technical field of automobile motor electric appliances. The first-class U-shaped grooves, the second-class U-shaped grooves and the third-class U-shaped grooves are sequentially arranged at intervals outwards in the radial direction of the rotor iron core, the second-class U-shaped grooves are located in openings of the first-class U-shaped grooves, the third-class U-shaped grooves are located in openings of the second-class U-shaped grooves, a fourth-class U-shaped groove and a fifth-class U-shaped groove are formed between every two adjacent first-class U-shaped grooves, and the fourth-class U-shaped groove and the fifth-class U-shaped groove are located in openings of the second-class U-shaped grooves. The fifth type U-shaped groove is located in an opening of the fourth type U-shaped groove, the second type U-shaped groove and the fourth type U-shaped groove are symmetrical about the left side wing or the right side wing of the first type U-shaped groove, and the fifth type U-shaped groove and the third type U-shaped groove are symmetrical about the left side wing or the right side wing of the first type U-shaped groove. By adopting a mode that each layer of permanent magnet poles are combined with permanent magnets with different lengths through magnetic barriers, the direction of a rotor magnetic field is adjusted, magnetic saturation is avoided, the output capacity is improved, wide magnetic conduction paths are provided between adjacent layers, and the utilization rate of the permanent magnets is improved.