53results about How to "Avoid short circuit current" patented technology

The invention discloses a reclosure method involving a distributed generation power distribution network based on wide area information. The reclosure method aims at achieving the technical purpose of guaranteeing the power supply reliability of loads. The reclosure method includes the following steps that directional elements, a circuit breaker and a protector are arranged, reclosure operational motion is set, whether a distributed generation has the isolated island operation capacity or not is judged, and protection and reclosure are conducted. Compared with the prior art, the problem of asynchronous reclosure caused by DG upstream protection maloperation generated by adjacent feeder line faults is solved, operation of switching DG control strategies and splitting an isolated island generated when a DG downstream line breaks down in a reclosure front acceleration protection action mode is avoided, DG control method switching and the action cooperative relationship between reclosure and protection are achieved by fully utilizing the wide area information, the reclosure method can be suitable for the power distribution network with DG access, the DG power supply capacity is brought into full play, the power failure range is reduced, the power failure time is shortened, and the power supply reliability of loads is guaranteed.

Provided is a starter motor control circuit capable of easily preventing the induction of a short-circuit current due to a ground fault in the power source line of a starter motor, in which a high current flows. A key switch (13) is connected with a battery (11), and a starter motor starting signal line (19) of a starter motor (18) is connected through a starter relay (16) with a start (ST) of the key switch (13). A protect relay (22) is disposed in a battery line (21) between the battery (11) and the starter motor (18). A ground fault detecting line (24) for detecting the ground fault of the battery line (21) is disposed between the battery line (21) and a controller (14). The controller (14) has a function to restrict the connecting actions of the starter relay (16) and the protect relay (22) when the ground fault of the battery line 21 is detected by a ground fault line (24), even if the key switch (13) is changed to the start (ST).

The invention discloses an electrocatalytic oxidation device running under an ultrahigh voltage condition and a process method. The electrocatalytic oxidation device comprises a multi-stage serial spherical particle active electrode reaction device and a direct-current stabilized power supply device capable of generating ultrahigh voltage, wherein the interior of the multi-stage serial spherical particle active electrode reaction device contains a set of multi-stage serial spherical particle active electrode reaction system; particle electrodes are equidistantly fixed into A rows, B columns and C layers through positioning insulated plastic rods; a first spherical particle active electrode is connected with the positive electrode of the power supply device, and a (A*B*C)th spherical particle active electrode is connected with the negative electrode of the power supply device; a power-generating main body of the direct-current stabilized power supply device capable of generating the ultrahigh voltage is a rotor-type frictional electrifier; a rotating wheel of the electrifier is driven by a frequency-variable motor; the rotating speed rate of the rotor-type frictional electrifier is adjusted by controlling different rotating speeds of the motor; and output voltage is stabilized by a voltage-stabilizing device to obtain ultrahigh direct-current voltage of 2000-50000V.

The invention relates to a double-fed wind turbine stator current calculation method with the low penetration capacity. The method includes the steps that flux linkages of a stator and a rotor of a double-fed wind turbine are firstly calculated according to the running work condition of the double-fed wind turbine in the normal running steady state; then a power frequency component of the stator current is calculated through a sequence network equivalent circuit under the fault condition; flux linkage values of the stator and the rotor of the double-fed wind turbine under the fault steady-state condition are obtained through the adoption of calculation results of power frequency loops; the flux linkage values of the stator and the rotor in the normal steady state and the fault steady state are substituted into a controlled source expression of a rotating frequency current, and a rotating frequency component is calculated; finally, the power frequency component, the rotating frequency component and an attenuation alternating component of the stator current are added to obtain a final stator current analysis calculation result. By means of the double-fed wind turbine stator current calculation method, an analytical solution of the stator end current of the double-fed wind turbine can be given, trouble caused by a large amount of slow simulation calculation through a simulation platform is avoided accordingly, and on-site protection setting work is better done.

The invention discloses a hybrid latch applied to a multi-power supply system on chip. The multi-power supply system on chip is a system in which a main power supply and a plurality of branch power supplies are integrated on a working chip for synergetic power supply, and a working chip comprises a plurality of working circuits. The hybrid latch comprises a two-input nor gate, a two-input nand gate, a pull-up P-channel metal oxide semiconductor (PMOS) transistor, a pull-down N-channel metal oxide semiconductor (NMOS) transistor and a phase inverter, wherein the input end and the output end ofthe nor gate are connected with the input end and the output end of the nand gate; the other input end of the nor gate is connected with the main power supply; the other end of the nand gate is connected with the branch power supplies; the pull-up PMOS transistor and the pull-down NMOS transistor are connected with the output ends of the nor gate and the nand gate respectively; and the output endof the nor gate is connected with the phase inverter, so that a signal is output to a part of working circuits. When the branch power supplies are instable after the main power supply is electrified and becomes stable quickly, a connected working circuit can be switched off and short-circuit current of the working circuit disappears, so that the battery consumption of the multi-power supply system on chip can be lowered.

The positive pole piece comprises a current collector and first safety coatings correspondingly arranged on the two outer side surfaces of the current collector, positive active layers are arranged on the two outer side surfaces of the first safety coatings, and the positive active layers are made of ternary positive materials. Second safety coatings are arranged on the two outer side surfaces of the positive electrode active layer, and end face safety coatings are arranged on the side edge end faces, except the tab position, of the positive electrode piece. The invention also discloses a preparation method of the positive pole piece, which comprises the following steps: uniformly stirring the raw materials to prepare each layer of slurry, sequentially coating the slurry on the current collector, and then stamping and coating the end surface; the invention also discloses an application of the positive pole piece in a lithium ion battery. Through the three-layer coating structure of the positive pole piece, the electrical performance and the safety performance of the lithium ion battery are ensured at the same time; the multi-layer coating method is adopted, so that the preparation efficiency is high; the positive pole piece is used as a composition structure of the lithium ion battery, so that the needling safety performance of the lithium ion battery is improved.

The invention provides a transmission line switching combination scheme establishment method and device. The method is applied to the technical field of power systems, and comprises steps: an initialcut-off line number k and the maximum cut-off line number kmax are set; k-self impedance of each to-be-detected node after the k lines are cut off is calculated; according to k-self impedance of eachto-be-detected node, a k-line qualified scheme and a k-line unqualified scheme are determined; the initial cut-off line number k is added to k+d according to a preset step d; if k+d < / = kmax, a node in the k-line unqualified scheme is regarded as a to-be-detected node, and the step of calculating k-self impedance of each to-be-detected node after the k lines are cut off is returned; and if k+d > kmax or the current to-be-detected node set is empty, current line switching combination scheme establishment is determined to be completed. The transmission line switching combination scheme establishment method and the device provided by the invention can quickly establish a switching combination scheme.

The invention relates to cooking equipment. The cooking equipment comprises a first cooking machine with first heating elements and a second cooking machine with second heating elements, and each cooking machine is provided with a temperature sensor; an energy supply is used for supplying energy to the first electric heating elements and the second electric heating elements and controlled by a control system; the cooking equipment, a power input part connected with a power supply, a current fuse which cuts off a current when overcurrent flows, and a load circuit controlling the cooking equipment are connected in series to form a closed circuit, a first surge protective device and a second surge protective device which are connected in series are connected with the series circuit of the power input part and the current fuse in parallel, and surge protection voltage V1 of the first surge protective device and surge protection voltage V2 of the second surge protective device are below thegeneral maximum voltage input from the power input part. Accordingly, on the condition that too high surge protection voltage or surface current is applied, dish processing can be completed by replacing manual work.

The invention discloses a three dimension electrode reaction unit, which is characterized in that short flow of wastewater is avoided by arranging plate-type main electrodes placed in a parallel staggered manner, insulation baskets with holes and particle electrodes filled therein, aerator pipes, insulation frames of which the surfaces have fine wire screens, support pins and tees, so that the wastewater is more uniformly mixed and the retention time is simultaneously reduced; the aeration is more uniform, the degree of mixedness of the wastewater is deepened, and the mass transfer efficiency is greatly improved; the partitioning design of the particle electrodes can omit a discharge opening of a traditional device, so that loading and unloading of the particle electrodes are more convenient and cleaner, and the partitioning design of the particle electrodes also can block a short-circuit current difficult to overcome in a traditional three dimension electrode reaction unit, and economy, green and high efficiency are realized; a gas-liquid mixture can be removed while mixing and effluent discharging are performed; the occurrence of a siphon problem can be avoided; the height of the wastewater can be controlled through the length of a discharging tube, thus a basic parameter, namely the filling amount of the particle electrodes, is controlled, and a better treatment effect is further obtained.

The invention relates to a DC side auxiliary commutation hybrid converter topological structure and a control method thereof. The DC side auxiliary commutation hybrid converter topological structure comprises a three-phase six-bridge-arm circuit and an auxiliary commutation circuit which is connected in parallel with the DC side of the three-phase six-bridge-arm circuit and has forward current controllable turn-off and forward and reverse voltage blocking capabilities. The auxiliary commutation circuit is connected with a connection point of an upper bridge arm and a lower bridge arm of each phase of bridge arm circuit in the three-phase six-bridge-arm circuit through a two-way valve which is arranged on each phase of alternating current bus in a three-phase alternating current bus and hastwo-way opening and two-way voltage withstanding capabilities. According to the DC side auxiliary commutation hybrid converter topological structure and the control method thereof of the invention, the auxiliary commutation circuit connected in parallel with the direct current side of the three-phase six-bridge-arm circuit is additionally arranged in the hybrid converter topological structure, sothat the commutation fault problem of the hybrid converter topological structure can be solved, and the topological structure is simple to implement and low in cost.

The invention discloses a PV string optimizer system which comprises N PV string optimizers. Each PV string optimizer corresponds to a PV assembly string, and each PV assembly string is formed by connecting at least two PV assemblies in series. The input end of each PV string optimizer is independently connected with the output end of the corresponding PV assembly string for independent maximum power tracking. The PV string optimizers 1-N are connected to a DC / AC inverter through corresponding cables 1-N. The PV string optimizer system has the maximum power point tracking and short-circuit fault disconnection protection functions at the same time, each PV assembly string carries out independent MPPT tracking, and when any PV assembly string is short-circuited, the other PV assembly strings still work normally, the problem of parallel mismatch is avoided, and the situation that the whole loop continuously generates a short-circuit current under the condition that one PV assembly string has a short-circuit fault is avoided.

The invention discloses a hybrid latch applied to a multi-power supply system on chip. The multi-power supply system on chip is a system in which a main power supply and a plurality of branch power supplies are integrated on a working chip for synergetic power supply, and a working chip comprises a plurality of working circuits. The hybrid latch comprises a two-input nor gate, a two-input nand gate, a pull-up P-channel metal oxide semiconductor (PMOS) transistor, a pull-down N-channel metal oxide semiconductor (NMOS) transistor and a phase inverter, wherein the input end and the output end ofthe nor gate are connected with the input end and the output end of the nand gate; the other input end of the nor gate is connected with the main power supply; the other end of the nand gate is connected with the branch power supplies; the pull-up PMOS transistor and the pull-down NMOS transistor are connected with the output ends of the nor gate and the nand gate respectively; and the output endof the nor gate is connected with the phase inverter, so that a signal is output to a part of working circuits. When the branch power supplies are instable after the main power supply is electrified and becomes stable quickly, a connected working circuit can be switched off and short-circuit current of the working circuit disappears, so that the battery consumption of the multi-power supply system on chip can be lowered.

The invention provides a level shift circuit, an integrated circuit and electronic equipment. The level shift circuit comprises an input module used for outputting a first control signal according to a received first power supply voltage signal, a first input voltage, a second input voltage, an anti-phase voltage of the first input voltage and an anti-phase voltage of the second input voltage; the control voltage generation module is used for receiving the first control signal and generating a plurality of node voltages according to the first control signal and the second power supply voltage signal; the output control module is used for generating a first output signal, a second output signal, a third output signal and a fourth output signal according to the node voltage and a first power supply voltage signal; or a fifth output signal, a sixth output signal, a seventh output signal and an eighth output signal are generated according to the second power supply voltage signal and the node voltage.