30results about How to "Reduce power shock" patented technology

An automatic switching single-phase rectifier bridge series circuit comprises an electromagnetic coil TA, a rectifying circuit, an integrated voltage regulator circuit and a power supply circuit which are connected with each other. The automatic switching single-phase rectifier bridge series circuit is characterized by further comprising a switching circuit. The rectifying circuit comprises a low-voltage rectifier bridge BG1 and a high-voltage rectifier bridge BG2 which are connected in series, and the low-voltage rectifier bridge BG1 is in serial connection with the input end of the high-voltage rectifier bridge BG2 and in parallel connection with the output end of the high-voltage rectifier bridge BG2 in a land shared mode. The switching circuit switches full-wave rectification of the low-voltage rectifier bridge BG1 and half-wave rectification of the low-voltage rectifier bridge BG1 and the high-voltage rectifier bridge BG2 by means of the situation whether to short the high-voltage rectifier bridge BG2. The automatic switching single-phase rectifier bridge series circuit has the advantages that full-wave rectification of the low-voltage rectifier bridge is controlled by controlling conduction of an MOS switch Q through a constant voltage comparator, when an input voltage is lower than a current-limiting threshold, energy is collected to the maximum extent, energy loss is reduced, and power supplied to a sensor is ensured under the conditions that a high-voltage line has low load and even has no load.

The invention belongs to the technical field of an electric power system and automation thereof, and discloses a method for setting a direct current commutation failure prediction link starting valueby integrating the supporting capacity of a phase regulator and interactive influences of multi-infeed direct current. The interactive influences in the multi-infeed direct current recovery process are considered, a quantitative evaluation method for the direct current recovery cost is proposed, and a differentiated setting principle for the multi-circuit direct current commutation failure prediction link starting value is provided accordingly, so that the occurrence probability of continuous commutation failure of multi-infeed direct current is reduced, and the power impact for a receiving-end power grid is reduced. The method can provide a reference for safe and stable running and control strategy formulation of a multi-infeed direct current system.

The invention relates to engineering machine speed changing box power cut-off control, aims at overcoming the defect that when an existing speed changing box power output cut-off control system cuts off power output or recovers power output, impacts can be generated, and discloses an engineering machine speed changing box power output cut-off control system and method. According to the braking pressure, the joint degree of a power cut-off clutch in a speed changing box is controlled; when the braking pressure value is smaller than P1, the joint degree of the power cut-off clutch is 100%; whenthe braking pressure value ranges from P1 to P2, the joint degree of the power cut-off clutch ranges from 0% to 100% and is reduced along with increasing of the braking pressure value; and when the braking pressure value is larger than P2, the joint degree of the power cut-off clutch is 0%. The slope control principle is used in the engineering machine speed changing box power output cut-off control system and method for controlling the power output of the speed changing box, disengaging and engaging of the power cut-off clutch are gradually changed, power cut-off and recovery are stable, theimpacts are reduced, the service life of power components is prolonged, and the work comfort is improved.

The present invention proposes a method for controlling the on-board energy storage system of urban rail trains based on a power-time curve. The on-board energy storage system of urban rail trains includes a traction motor, a four-quadrant inverter, two bidirectional DC-DC converters, A control module, a storage battery, a super capacitor, a resistance energy consuming device and a catenary; in the control method, double cut-off frequencies are used to control the charging action of the storage battery and the super capacitor; the beneficial technical effects of the present invention are: The control method of the on-board energy storage system of urban rail trains based on the power-time curve, this scheme can give full play to the advantages of high absorption efficiency and large absorption power of super capacitors, reduce the power impact on the battery, improve the performance of the hybrid energy storage system, reduce the Unnecessary heat dissipation.

The present invention relates to a linear compressor, and more particularly, to a linear compressor which supplies a necessary cooling capacity through a natural cooling capacity modulation and a forcible cooling capacity modulation, and a cooling system using the same. The linear compressor according to the present invention includes a compression space into which refrigerant is sucked, a movable member which linearly reciprocates to compress the refrigerant sucked into the compression space, one or more springs which are installed to elastically support the movable member in a motion direction of the movable member, a motor unit which includes a motor and a capacitor connected in series to the motor so as to make the movable member linearly reciprocate, and a motor control unit which performs a natural cooling capacity modulation according to a load by reciprocation of the movable member.

The invention relates to a driving system of an electric vehicle, in particular to an electromagnetic variable-torque driving system of an electric vehicle. The electromagnetic variable-torque driving system comprises an electromagnetic variable-torque driving device, a power cell, an electronic controller, a three-phase bridge type full control inverter circuit and a three-phase rectification circuit, wherein the electromagnetic variable-torque driving device comprises a three-phase separate excitation type synchronous motor and an electromagnetic variable-torque motor, and a rotor of the three-phase separate excitation type synchronous motor is connected with an inner rotor of the electromagnetic variable-torque motor; the power cell is connected with an input end of the three-phase bridge type full control inverter circuit, and an output end of the three-phase bridge type full control inverter circuit is connected with an armature winding of the three-phase separate excitation type synchronous motor; a magnetic pole winding of the inner rotor of the electromagnetic variable-torque motor is connected with an excitation winding of the three-phase separate excitation type synchronous motor through the three-phase rectification circuit, and an outer rotor of the electromagnetic variable-torque motor is connected with a hub. According to the electromagnetic variable-torque driving system disclosed by the invention, a completely new concept of electromagnetic variable-torque drive is provided, the electromagnetic variable-torque drive is realized through a specific structure, and an electric wheel of the electromagnetic variable-toque drive can have a great market application prospect.

The invention discloses a commutation failure prediction control starting voltage value optimization method, which comprises the following steps of: simulating and calculating the power impact of primary commutation failure of each loop of direct current, and calculating a power impact contribution degree index, calculating a reactive influence degree index according to the direct-current operation state and the equivalent impedance matrix of the receiving-end alternating-current power grid, calculating parameter setting priority indexes, and sorting the indexes from large to small, and determining a commutation failure prediction control starting voltage value of each loop of direct current. The method provided by the invention can effectively reduce the overall power impact caused by commutation failure, and avoids adverse effects on the voltage stability of the receiving-end alternating-current power grid caused by overlarge multi-loop direct-current reactive power demand at the same time.

The invention discloses a distributed cooperative absorption method for urban rail transit braking energy. Braking energy utilization devices of adjacent stations are triggered to be put into operation by controlling the absorption voltage of a traction substation braking energy utilization device, so that the regenerative braking peak power of a train which enters a station can be jointly absorbed by the energy utilization devices of the multiple adjacent stations, the power impact on a single station is reduced, better utilization of the regenerative braking energy in a subway system is facilitated, and the probability of transmitting electric energy back to an urban power grid is reduced.