102results about How to "Reduce input current" patented technology

The invention discloses a variable-frequency air-conditioner current frequency limiting method and device. A variable-frequency air-conditioner comprises a rectification circuit, a power factor correction PFC circuit and a compressor. The input end of the PFC circuit is connected with the output end of the rectification circuit. The output end of the PFC circuit is connected with the compressor. The method comprises the following steps that the input current effective value Iin_rms of the variable-frequency air-conditioner is acquired; the preset current frequency limiting threshold is subtracted from the input current effective value Iin_rms so that a current difference value of the input current effective value Iin_rms and the current frequency limiting threshold is acquired, and the current difference value is judged; if the current difference value is greater than or equal to a first threshold, the compressor is controlled to stop operation; and if the current difference value is greater than or equal to a second threshold and less than the first threshold, the compressor is controlled to perform underclocking operation according to the preset step length, wherein the second threshold is less than the first threshold so that output power is reduced by controlling operation frequency of the compressor and then an objective of reducing input current is achieved, the heating condition of an input circuit is improved and an over-current fault can be avoided.

The invention provides a free piston engine, which comprises a cylinder block, a compression accumulator, a pump station and a piston assembly, and also comprises a first proportional overflow valve, a proportional pressure reducing valve, a proportional velocity regulating valve and a pressure sensor; a piston chamber in the cylinder block is divided into a combustion chamber, an air intake chamber, a balance chamber, a pump chamber and a compression chamber by the piston assembly. As a pipeline connected with two inlets of a compression main port and a compression starting port of the compression chamber and the compression accumulator is provided with the proportional pressure reducing valve, the proportional velocity regulating valve, a reversing valve, the proportional overflow valve and the pressure sensor, according to the detection signal of the pressure sensor connected with the compression accumulator, the reversing valve is switched between the compression accumulator and an oil supply accumulator, and therefore oil supply work on high and low-pressure two oil lines is completed by utilizing one hydraulic pump station; moreover, after hydraulic oil in the compression accumulator flows through the proportional pressure reducing valve, stable pressure can be obtained and supplied for the compression chamber, so that the pressure of the inlet of the compression chamber is stable.

A differential cascode amplifier has first and second cascode circuits, driven by two differential signal sources including input resistances.The first cascode circuit includes a first input transistor having a first collector, a first emitter, and a first base, and a first output transistor having a second collector, a second base, and a second emitter coupled to the first collector. The second cascode circuit includes a second input transistor having a third collector, a third emitter, and a third base, and a second output transistor having a fourth collector, a fourth base, and a fourth emitter coupled to the third collector. The amplifier has a first connection connecting the first base to the fourth base, and a second connection connecting the second base to the third base.This cross-connected differential cascode architecture provides doubled output bandwidth and current gain (in dB), further increasing input impedance and output swing.

The invention provides a winding unitized parallel winding structure of an alternating current motor stator. The alternating current motor stator adopts a concentrated winding structure to be connected with a phase winding branch, with independent neutral points, in parallel in a star connection mode; the number of phases of an alternating current motor is m; the number of stator slots is Z; the number of pole-pairs is P; Z can evenly divide m; the stator slots of the alternating current motor are divided into Z / m units; in each unit, a parallel branch of a corresponding phase is wound on each tooth; tail ends of the parallel branches on each the unit are connected with one another, so as to form a neutral point of star connection; the Z / m units form Z / m independent disconnected neutral points. The winding unitized parallel winding structure reduces the length of a connecting lead at the end part of the motor, reduces copper use level and copper consumption, improves the motor efficiency, power density and slot utilization, and simplifies the winding technology; in addition, the fluctuation of cogging torque is correspondingly restrained, and the counter electromotive force sine of windings is improved.

The invention relates to the technical field of electrical application equipment in the field of machinery, in particular to an intelligent motor which comprises a rotor, a stator, a rotating shaft and a motor shell. The stator is fixed on the inner wall of the motor shell, the rotating shaft penetrates the stator, the rotor is positioned inside the stator, and two ends of the rotating shaft are connected with the motor shell. The intelligent motor is characterized by comprising processors and a display unit, and a main processor is connected with a motor start protecting device and a motor rotating speed adjusting device. The intelligent motor has the advantages that the circumstance of overlarge current when the motor is started is reduced, and overhigh speed of the motor, overheating and burning of a coil winding during overloading in the process of working are prevented.

The invention discloses an intelligent building electric power distribution device, which comprises a main circuit which supplies electricity for buildings, wherein the output end of the main circuit is connected with an energy-saving composite control circuit which is connected with a power distribution circuit which supplies electricity for each electrical appliance and a direct current voltage stabilizing circuit which supplies electricity for the energy-saving composite control circuit. The energy-saving composite control circuit mainly comprises a straight-through or power-saving control circuit and a power-saving shifting control circuit. The intelligent building electric power distribution device not only can satisfy the requirement of low-voltage distribution, but also can filter clutter, optimize power supply parameters, improve power consumption efficiency, reduce the waste of residual or excess electric energy, maximally save electric energy through the automatic adjustment of the power-saving shifting control circuit under the circumstance of guaranteeing the normal work state of electric equipment, thereby saving the expenditure of electricity charge, and the power saving rate is generally between 15% and 25%.

A differential cascode amplifier has first and second cascode circuits, driven by two differential signal sources including input resistances. The first cascode circuit includes a first input transistor having a first collector, a first emitter, and a first base, and a first output transistor having a second collector, a second base, and a second emitter coupled to the first collector. The second cascode circuit includes a second input transistor having a third collector, a third emitter, and a third base, and a second output transistor having a fourth collector, a fourth base, and a fourth emitter coupled to the third collector. The amplifier has a first connection connecting the first base to the fourth base, and a second connection connecting the second base to the third base. This cross-connected differential cascode architecture provides doubled output bandwidth and current gain (in dB), further increasing input impedance and output swing.

The invention discloses an adaptive charging control circuit and control method for a switch charger. When a reference current adjusting circuit determines that an over-current phenomenon occurs at an input current of a switch charger, an input current reference signal is reduced step by step, thereby reducing the input current of the switch charger; and thus the output voltage of the input power supply returns to a safety value range. Because with a step-by-step input current reduction method, minimization of the charging current of the switch charger can be avoided and a large value can be kept, so that rapid charging can be realized.

The invention relates to a double flexible pair-based three-degree-of-freedom precision adjustment parallel mechanism, comprising three groups of motion branch chains which are connected in parallel and have the same structure, wherein the three groups of motion branch chains are in uneven circumference distribution at three extending ends of an immersion unit by taking a center hole of the immersion unit as a center; each group of motion branch chain comprises a linear motion assembly, a double flexible pair connecting rod assembly, a mechanical anti-collision assembly, a Z-direction displacement measuring assembly and a gravity compensation assembly. The double flexible pair-based three-degree-of-freedom precision adjustment parallel mechanism is used for realizing installation, fixationand space position adjustment of the immersion unit of an immersion type photoetching machine and realizing micron-level positioning of the immersion unit; double flexible pairs are adopted, the structure is simple and compact, and the advantages of no friction and no need of lubrication are achieved; the wholly mechanism adopts a parallel mechanism, the rigidity is high, the response is quick, the adjustment range is large, modular design and assembly are adopted, and the mechanism can be used for three-degree-of-freedom precision adjustment in other occasions except the immersion type photoetching machine.

The invention discloses a multiphase DC-DC converter including an input end for receiving DC input voltage, a plurality of parallelly connected single-phase DC-DC converters for performing DC-DC conversion on DC input voltage, an output end for outputting the DC output voltage converted by the plurality of single-phase DC-DC converters, and an equalization circuit which is serially connected with the plurality of parallelly connected single-phase DC-DC converters between the input end and the output end of the multiphase DC-DC converter and is used for equalizing the current of the single-phase DC-DC converters.

The present invention discloses a circuit for a low-offset operational amplifier, and is applied to the low-offset operational amplifier, so as to enable the low-offset operational amplifier to have a relatively low input current. The circuit includes an input current compensation circuit, an input amplification stage circuit, an output stage circuit, and a phase compensation circuit. The input current compensation circuit is used for compensating an input current introduced due to adoption of bipolar input geminate transistors, so as to reduce input offset of the operational amplifier. The input amplification stage circuit adopts a folded cascode structure, and uses bipolar devices as input geminate transistors to amplify a micro input differential signal, so as to obtain an output value. The output stage circuit is used for providing large current carrying capacity, so as to ensure the operational amplifier to drive a post-stage circuit normally. The phase compensation circuit is used for compensating a phase margin of the operational amplifier, so as to ensure the operational amplifier to work stably in a specified usage mode.

A control unit and a method for triggering personal protection devices are proposed, which charge an energy reservoir for the control unit via a charging circuit. The charging circuit sets a charging rate for charging as a function of a signal generated outside the charging surface.

The invention discloses a control system for an energy saving electro-hydraulic air-changeable door, which can realize the recovery of energy and recycle, comprises constant pump, one-way valve, safe valve, energy storage device, hydraulic actuator, air door, pressure test device and high-speed switch valve. The hydraulic actuator comprises oil cylinder, piston and piston bar. The constant pump inputs energy to the energy storage device. The one-way valve between the energy storage device and the hydraulic pump can prevent the pressure oil in the energy storage device returning. The high-pressure energy storage device is connected with the pressure port of three-way high-speed switch valve and the left cavity of cylinder is connected with the control port of high-speed switch valve. When the right cavity of cylinder is not connected with the oil return port of high-speed switch valve, the oil return port of high-speed switch valve is connected with the oil tank. The energy storage device provides energy to the hydraulic actuator. As the pressure test device measures the pressure value at the outlet of energy storage device, energy is filled in the energy storage device in time so as to decrease the energy consumption of system greatly.

The invention relates to an input current closed-loop amplitude limiting method and system during a grid voltage drop of an air conditioning system. The method comprises the following steps: limiting the amplitude of electromagnetic torque compensation TeComp through an input current effective value and an input current effective value protective threshold value; adjusting the electromagnetic torque given quantity Te_ref through the electromagnetic torque compensation TeComp with limited amplitude to obtain the final electromagnetic torque given quantity for compressor operation; processing the final electromagnetic torque given quantity for compressor operation through a maximum torque / current ratio control module to obtain the direct-axis current given quantity Id_ref and the quadrature-axis current given quantity Iq_ref; performing vector control on a compressor to realize limiting on the input current effective value Iin_rms. According to the method, during the grid voltage drop, the operation efficiency of the compressor is limited through limiting the output electromagnetic torque of the compressor, the effects of reduction of the compressor power and reduction of the input current are realized, the method has a high response speed, the input current is within the overcurrent capacity of an input circuit, the circuit is prevented from being damaged, and normal operation of the system is guaranteed.

The invention provides an elevator energy accumulation control device and method. The device comprises a bus voltage dynamic control unit, a rectification control unit, an energy accumulation discharging unit and an inversion control unit. The bus voltage dynamic control unit is used for detecting the running state of an elevator, direct-current bus voltage of an elevator power supply system and energy accumulation voltage stored by the energy accumulation discharging unit in real time and sending out a rectification control instruction or a power supply control instruction. The rectificationcontrol unit is used for rectifying a commercial power alternative-current source into first direct current according to the rectification control instruction. The energy accumulation discharging unitis used for storing the first direct current or outputting second direct current according to the power supply control instruction. The inversion control unit is used for converting the second directcurrent into third direct current according to the power supply control instruction for use of a motor of the elevator. By means of the elevator energy accumulation control device, feedback electricenergy of the elevator can be stored and consumed in next time running, and feedback and contamination to a power grid can be avoided; and meanwhile, the electricity consumption of power meters of users can be reduced, and it is beneficial for users to configuration of power supply capacity.

The invention discloses an adaptive voltage frequency limiting method and device for an input voltage of a PFC circuit. An output end of the PFC circuit is connected with a load which is a compressor. The method comprises steps that an effective value of the input voltage of the PFC circuit is acquired; a voltage frequency limiting threshold of the compressor is acquired according to the effective value of the input voltage, the outdoor environment temperature and the indoor environment temperature; the compressor is controlled for realizing frequency limiting operation according to the voltage frequency limiting threshold. The method is advantaged in that the temperature of a heating device of an input circuit and an input current are reduced through adjusting operation frequency of the compressor, and system safety and reliability are improved.

The invention provides a direct current-direct current switching converter. When the first voltage drops, a converter control adjusting circuit can reduce the second current corresponding to a secondary side circuit according to changes of the duty ratio so that the output power of the secondary side circuit can be reduced. When the first voltage drops, the maximum current of a converter output load can be reset by the converter control adjusting circuit according to the changes of the duty ratio so as to reduce the load current, and therefore the output power of the converter is reduced, the input current of a primary side circuit is forced to be not increased under the condition that the input voltage drops, a switching tube of the primary side circuit is protected and cannot be burnt out due to the high current, and the service life of the direct current-direct current switching converter is effectively prolonged.

The invention provides a power system that can improve power factor and power loss, and realize miniaturization of a transformer comparing to the past, wherein the power system (100) comprises the following components: a power transformer (110) that can change AC100V to AC24V; and a plurality of power source units (200-1 to 200-n) connected to the power transformer (110). The power source units (200-1 to 200-n) comprises the following components: a rectification circuit (210) that rectifies the AC24v through a synchronous rectifier bridge; a power factor improving circuit (220) that improves power factor to voltage after rectification; and an output circuit (230) that outputs the direct current voltage. The power factor improving circuit (220) comprises an induction coil L, a FET (1), a FET (2), and a control circuit (222) that controls the switch of the FET (1) and the FET (2), wherein the control circuit (222) adjusts dutyfactor of the FET (1) and the FET (2) so as to make the expected DC voltage output from the output circuit (230).

The invention discloses a distributed-type wheel-edge electrically-driven power assembly of an electric vehicle and a method. In the power assembly, a two-in-one speed reducer is internally provided with two gear speed reducing structures without interference in structure, and the two gear speed reducing structures are integrally mounted through a shell; a first motor and a second motor are symmetrically distributed on the left side and the right side of the two-in-one speed reducer correspondingly and connected with input shafts of the two gear speed reducing structures in the two-in-one speed reducer; a first half shaft assembly and a second half shaft assembly are arranged on the left side and the right side of the two-in-one speed reducer correspondingly, one ends of the first half shaft assembly and the second half shaft assembly are connected with output shafts of the two gear speed reducing structures in the two-in-one speed reducer correspondingly, and the other ends of the first half shaft assembly and the second half shaft assembly are connected with a first wheel and a second wheel correspondingly, and the output shaft and the corresponding input shaft of each gear speedreducing structure in the two-in-one speed reducer are parallel and not collinear; and the whole power assembly is distributed in a mirror-image symmetrical mode along the center of the two-in-one speed reducer of the power assembly. A feasible arranging scheme of the wheel-edge motor-driven power assembly adopted by the electric vehicle has the characteristics of being compact in structure and simple and convenient to mount.

The invention discloses an efficient regulated power supply circuit. A part of power consumed by the flow of input current in the regulated power supply circuit through a circuit of which the voltage drop is a difference between an input voltage and an output voltage is converted into a part of output power by using an unregulated isolated DC-DC (Direct Current to Direct Current) circuit, so that the input current of the circuit is reduced, and the power efficiency of the entire regulated power supply circuit is increased. The regulated power supply circuit provided by the invention mainly comprises the unregulated isolated DC-DC circuit, a voltage regulator, an inductor and a capacitor, wherein the output port of the unregulated isolated DC-DC circuit is connected with the input port of the voltage regulator, and is used for supplying input power to the voltage regulator; the output voltage of the voltage regulator is the output voltage of an entire regulated power supply; the input port of the unregulated isolated DC-DC circuit and the output ports of the inductor and the regulated power supply are serially connected in sequence; and the input voltage of the regulated power supply circuit is applied to the two ends of a series circuit.

The invention relates to a handheld testing device used for testing of a refrigerator electric control board and a testing method. The handheld testing device is in direct communication with the refrigerator electric control board; the corresponding forced load working mode of the handheld testing device is set according to the fault phenomenon of the whole machine, then a corresponding control instruction and a corresponding code are generated, the control instruction is sent to the refrigerator electric control board, and the refrigerator electric control board controls corresponding loads to work independently and feeds back the operation situations of the corresponding loads; when starting of the corresponding loads fails, it is judged that the electric control board has a fault; when starting of the corresponding loads succeeds, an output port of the corresponding loads of the refrigerator electric control board is tested according to the displayed corresponding code, and whether the electric control board has a fault or not is judged. The after-sale repair convenience and accuracy are improved; the repairing frequency is reduced; the after-sale repair expenses of users are reduced; the market reject ratio of electric control boards is reduced; the brand credibility is improved.

The invention provides a self-locking and interlocking switch with multiple grades. The self-locking and interlocking switch with multiple grades has the technical characteristics that the multiple grade switch of self-locking and interlocking is composed of a 12 voltage direct current source, operation amplifier integrated circuits (IC) 1, an output voltage even division circuit, and a direct current source voltage division circuit. The model of the operation amplifier IC1 is LM324. Each operation amplifier IC1 can form a self-locking and interlocking switch circuit with 4 grades. The structure of each grade self-locking and interlocking switch circuit is the same. Components and connection feature of a second grade and other grade self-locking and interlocking switch circuits are identical with components and connection feature of a first self-locking and interlocking switch circuit. According to the multiple self-locking and interlocking switch, defaults of mechanical self-locking and interlocking switch are overcome. Due to the fact that input impedance of the operational amplifier is high, input current of key switch is minimal, input and output electrical level of the switch meet the requirement of interface electrical level of a digital circuit, and the multiple grade switch of self-locking and interlocking can share work power source with the digital circuit. The multiple grade switch of self-locking and interlocking is characterized in that application range of voltage is wide, and grade can be arbitrarily designed.

The invention discloses a winding device of textile equipment, and belongs to the field of textile equipment. The winding device of the textile equipment comprises two supporting vertical plates whichare symmetrically arranged, a rotating shaft is rotatably connected between the two supporting vertical plates, a drum is fixedly connected to the positioning outer wall of the rotating shaft, slideways are correspondingly formed in the opposite side walls of the two supporting vertical plates, a sliding block which is in fit with the outer wall of the upper end of the drum is slidably connectedbetween the two slideways, slide rheostats are arranged on the side walls of the slideways, a variable resistance sliding sheet matched with the slide rheostats is fixedly connected to the side wall of the sliding block, an energy storage box and a cutting box are fixedly connected between the two supporting vertical plates, and automatic cutting mechanisms connected with the sliding block are arranged in the energy storage box and the cutting box. According to the winding device, the rotation speed of the drum is controlled while winding a textile cloth, so as to prevent the pulling damage ofthe textile cloth when the diameter of the drum is large, the textile cloth at the upper end of the drum can further be automatically cut off, and using is more convenient.

The invention discloses a control system for an energy-recovery electro-hydraulic air-changeable door. The control system, which can realize the recovery of energy and recycle, comprises constant pump, one-way valve, safe valve, energy storage device, hydraulic actuator, air door, pressure test device and high-speed switch valve. The hydraulic actuator comprises oil cylinder, piston and piston bar. The constant pump inputs energy to the energy storage device. The one-way valve between the energy storage device and the hydraulic pump can prevent the pressure oil in the energy storage device returning. The high-pressure energy storage device is connected with the pressure port of three-way high-speed switch valve and the left cavity of cylinder is connected with the control port of high-speed switch valve. When the right cavity of cylinder is connected with the oil return port of high-speed switch valve, the oil return port of high-speed switch valve is connected with the low-pressure energy storage device. The energy storage device provides energy to the hydraulic actuator. As the pressure test device measures the pressure value at the outlet of energy storage device, energy is filled in the energy storage device in time so as to decrease the energy consumption of system greatly.

The invention discloses a buffer control circuit and a buffer control method of a motor device. Startup operation of the motor device M is realized through a buffer resistance circuit, and the input voltage of the motor voltage M is reduced by using the voltage division effect of a resistor for the input voltage, so that the input current of the motor device M is reduced. The used buffer resistance circuit is relatively simple in structure, and the safety of the motor device M is guaranteed.

The invention discloses a vector control method for a frequency converter, applied to the frequency converter that outputs electric energy to a motor through an LC output filter. The method comprisesthe following steps: obtaining an output current of the frequency converter; obtaining a compensation current value corresponding to the current of a filter capacitor according to the output current of the frequency converter, electrical parameters of the LC output filter, and the reference voltage of the frequency converter; obtaining a control parameter of the frequency converter according to the compensation current value; and controls the frequency converter by using the control parameter of the frequency converter. By using the compensation current value obtained by the output current ofthe frequency converter, the electrical parameters of the LC output filter and the reference voltage of the frequency converter, the control parameters of the frequency converter are obtained, therebycontrolling the frequency converter to output a relatively ideal current, adjusting the reactive current output by the frequency inverter, and reducing the output voltage of the inverter, so as to reduce the input current of the motor and reduce the loss of the motor. The application also discloses a vector control system and device for a frequency converter.

The invention discloses a counteracting circuit for input current of an operational amplifier. The counteracting circuit comprises a differential input stage, an input current counteracting circuit and an output stage, a first end of the differential input stage is connected with a first end of the input current offset circuit and then connected to a positive and negative input end, a second end of the differential input stage is connected with a second end of the input current offset circuit and then connected to a power supply, and a third end of the differential input stage is connected with a third end of the input current offset circuit and then connected to a bias voltage. The fourth end of the differential input stage is grounded after being connected with the fourth end of the input current offset circuit; the fifth end of the differential input stage is connected with the first end of the output stage, and the second end of the output stage is connected to a voltage output end. According to the operational amplifier, the input current of the differential input stage is greatly reduced, and the input impedance of the operational amplifier approaches to infinity.

The invention discloses a handheld active control type electric welder. The electric welder comprises a power module and an operation handle, wherein a main control panel, a charging / discharging circuit, a power output board and a welding head are fixedly arranged on the operation handle; the charging / discharging circuit comprises a charging switch and a plurality of charging / discharging units arranged in parallel; each charging / discharging unit comprises an electrolytic condenser and a discharging switch; each of the charging switch and the discharging switch is an MOSFET tube. The handheld active control type electric welder disclosed by the invention has the advantages of high integration degree, small size, low cost and the like, and can realize the active control of the output time of welding current, so that the success rate of welding is increased; the electric welder adopts the confluence of the parallel charging / discharging units, so that each MOSFET tube is guaranteed to normally work; besides, the large current for welding is satisfied, so that the MOSDET tubes can be used for controlling large current.

The invention relates to the technical field of hydraulic control drive, and in particular relates to an energy-saving motor for hydraulic pump drive. The energy-saving motor comprises a rotor, a stator, a rotating shaft and a motor shell, wherein the motor shell is provided with a junction box; the stator is provided with a coil winding; the junction box is provided with a wiring terminal, a processor, a driving circuit and a detection device for detecting the output current of the driving circuit; and the detection device, the wiring terminal and the driving circuit are electrically connected with the processor. When the motor has an extremely high load, the rotating speeds of the rotor and rotating shaft of the motor are reduced, the heating capacity of the coil winding is improved, the resistance of the coil winding is increased, the input current of the motor is reduced, namely the output current of the driving circuit is reduced, the processor obtains the control information by comparing the detected current information with the set limit data and transmits the control information to the driving circuit, and the motor is prevented from being excessively heated by reducing or cutting off the output current of the driving circuit; and therefore, the functions of protecting the motor and saving the energy are realized.

The invention provides a switch array circuit and a communication device of an automobile diagnosis system. The switch array circuit is connected between a controller and a connector. The switch array circuit comprises a power supply module, a driving module, a transmit-receive module and a switch array, wherein the switch array a plurality of switch channels formed by light-operated MOS relays; each switch channel comprises a power port, a drive port, a data port and an output port; the driving modules has a plurality of driving ends; and the transmit-receive module has a plurality of transmit-receive ends for transmitting and receiving diagnosis signals; the power port of each switch channel is connected with the power supply module, the drive port of each switch channel is connected with a corresponding drive end of the driving module, the data port of each switch channel is connected with a corresponding transmit-receive end of the transmit-receive module, and the output port of each switch channel is connected with a corresponding pin of the connector. The switch array circuit adopts the switch array formed by the light-operated MOS relays, and the light-operated MOS relays belong to contactless switches, and have no noise and long service lives.