32results about How to "Change the output voltage" patented technology

The invention provides a feedback control circuit for staged charging of a vehicle-mounted charger and an implementation method. Voltage loop and current loop double closed-loop control is adopted, aresistance voltage-dividing network is connected with a battery pack in parallel, sampling of the charger is performed and a sampling value is inputted into a constant-voltage control loop or a constant-current control loop; the MCU is connected with the constant-voltage control loop and the constant-current control loop and outputs two paths of duty ratios, only a constant-voltage control or constant-current control working mode is adopted at the same time, and only feedback signals of voltage feedback or current feedback are outputted through the OUT end. The charging process is enabled to follow the 'Mass curve' of the battery pack so that the charging efficiency is improved, the service life of the battery pack is protected, adjustment is made according to different vehicle-mounted charging environments, complex operation of the user is not needed, and the flexibility and the convenience of the vehicle-mounted charger of the electric vehicle are improved.

The invention discloses a high-temperature high-pressure vacuumizing test device and an operating method thereof. The high-temperature high-pressure vacuumizing test device comprises a vessel holder (3), a console (4), a stander (1) for installing the vessel holder (3) and the console (4) and an interface (2), wherein a test vessel (6) which is used for arranging a test sample (5) and provided with a sealing cover is arranged in the vessel holder (3), and the high-temperature high-pressure vacuumizing test device also comprises a pressure system, a temperature system and a vacuum pump (8); the pressure system is arranged in the console (4), and the pressure system is communicated with the test vessel (6) to adjust the pressure value in the test vessel (6); the temperature system consists of a part which is arranged in the console (4) and a part which is arranged in an inner cavity of the test vessel (6), and the two parts of the temperature system are communicated with each other to adjust the temperature value in the test vessel (6); the vacuum pump (9) is arranged on the stander. The high-temperature high-pressure vacuumizing test device integrates the temperature system, the pressure system and the vacuumizing system.

The invention relates to a position sensor for a non-contact clutch, which solves the problems that the poor contact existing in the prior position sensor of the non-contact clutch leads to poor operational reliability and so on, The position sensor for the non-contact clutch comprises a shell, a rotor, a circuit board and so on, wherein a magnetic steel ring is arranged in the cylindrical rotor, the inner wall of the magnetic steel ring is symmetrically provided with two permanent magnet blocks respectively, and a cavity is formed between the two permanent magnet blocks; and the middle part of the circuit board is connected with an A Hall chip and a B Hall chip through two conducting member bars respectively, and the A Hall chip and the B Hall chip are positioned in the cavity between the two permanent magnet blocks. The sensor solves the problem of contact wear and prolongs service life; the sensor has good linear output characteristic and ensures that an output signal is more accurate and stable; the adopted Hall chips have functions of programmable property and temperature compensation, can flexibly change parameters of output voltage according to the requirement of customers, and automatically compensate and calibrate the magnetic field drift when the magnetic field intensity of a magnet drifts with the change of the temperature.

The invention provides a control system for a permanent magnet synchronous motor. The control system mainly comprises a three-phase power source, a rectifying circuit, a logical circuit, the permanent magnet synchronous motor, a detection circuit, an external control panel, an external interface, a digital control circuit, a brake resistor and a power amplification circuit. The external control panel is used for setting the rotation speed of the permanent magnet synchronous motor and the time when the permanent magnet synchronous motor starts and stops and transmits the given information to the digital control circuit, and the digital control circuit controls the power amplification circuit to form voltage signals needed by control over the permanent magnet synchronous motor.

The invention relates to a microwave power control system, by means of a feedback control circuit, voltage of a magnetron resonant cavity polar plate is adjusted, so that adjustable continuous linearity of microwave output power is achieved. The system is mainly composed of an independent magnetron filament power supply, voltage-power non-linear correction and a feedback controlled magnetron resonant cavity power supply circuit. By means of needed power density, control voltage Vc is output by the voltage-power non-linear curve correction, and the Vc serves as a feedback controlled reference signal. The reference signal is compared with a feedback signal, a servo motor is controlled to act, an electric brush is driven to slide, output voltage of an autotransformer is changed, then a resonant cavity of a magnetron is supplied with power by a boosting transformer, so that microwaves with different power output by the magnetron is controlled. Continuous and changeable power input is provided for a to-be-dried object in microwave drying, and the applicability of drying equipment is greatly improved.

The invention provides a constant resistance control loop. The constant resistance control loop comprises an input voltage differential sampling unit used for attenuating a voltage signal of an external constant voltage input power source, and outputting the attenuated voltage signal to a reference input pin of a first DAC; the first DAC used for outputting a constant current control voltage signal to a constant current control loop according to the attenuated voltage signal and an input code value of the first DAC; the constant current control loop used for controlling the constant current which changes with an input voltage signal of the external constant voltage input power according to the constant current control voltage signal when the constant resistance is output; the output end ofthe constant resistance control loop outputs a constant resistance value according to the ratio of a full-scale code value of the first DAC to the input code value, attenuation coefficients of the input voltage differential sampling unit and the relationship between output coefficients of the constant current control loop. According to the constant resistance control loop, the speed and accuracyof constant resistance output control are improved.

The invention provides a battery pack, a tool system and a charging system. The battery pack comprises a shell assembly, a battery pack accommodated in the shell assembly and a control assembly electrically connected with the battery pack, wherein the control assembly is rotatably arranged, when the control assembly is in a first state, the battery pack outputs a first voltage value; when the control assembly rotates to a second state, the battery pack outputs a second voltage value; when the control assembly rotates to a third state, the battery pack outputs a third voltage value; wherein thefirst voltage value is smaller than the second voltage value, and the second voltage value is smaller than the third voltage value. Compared with the prior art, the battery pack disclosed by the invention is advantaged in that the serial-parallel connection state switching of each battery cell module in the battery pack is realized by utilizing the rotation of the control assembly, so the outputvoltage of the battery pack is changed, and adaptability of a tool system with the battery pack is improved.

The invention provides a battery pack, a tool system and a charging system. The battery pack comprises a shell assembly, a battery pack accommodated in the shell assembly and a control assembly electrically connected with the battery pack, wherein the control assembly is rotatably arranged and is provided with at least three target areas, when the control assembly rotates to a first target area, the battery pack outputs a first voltage value, when the control assembly rotates to a second target area, the battery pack outputs a second voltage value, when the control assembly rotates to a thirdtarget area, the battery pack outputs a third voltage value, the first voltage value is smaller than the second voltage value, and the second voltage value is smaller than the third voltage value. Compared with the prior art, the battery pack is advantaged in that the battery pack is in butt joint with connecting pieces in different target areas through rotation of the control assembly, series-parallel connection state switching of all the battery cell modules in the battery pack is achieved, then the output voltage of the battery pack is changed, and adaptability of a tool system with the battery pack is improved.

The invention relates to a dynamic circular dichroism regulation and control device and system based on memory alloy, in particular to a circular dichroism regulation and control system. The dynamic regulation circular dichroism device based on the memory alloy comprises a substrate, a grid electrode, a source electrode, a drain electrode, a first graphene layer, a second graphene layer, a memory alloy layer and a metal structure layer. When the device needs to be regulated, the external environment of the device is changed, and then the memory alloy layer is deformed, so that the shapes of the first graphene layer and the second graphene layer are changed, the carrier density and conductivity in the first graphene layer and the second graphene layer are changed, the output voltage of the electrode of the device is further changed, and when circular dichroism signals are irradiated by left-hand circularly polarized light and right-hand circularly polarized light respectively, the output voltage difference of the device is related, that is, the circular dichroism signal of the device is changed by changing the output voltage of the device.

The invention relates to a narrow-band tunable filter with a low frequency band, which solves the problem that the filtering frequency band of a low-frequency signal is difficult to adjust in the traditional filter circuit design. The voltage-controlled capacitor chip is adopted to replace a traditional variable-capacitance diode method, so that the problem of waveform distortion caused by superposition of a variable-capacitance diode control channel and a signal channel is solved. And meanwhile, the LRC filter circuit is improved and combined, so that the problem of low quality factor of thetraditional RC filter circuit is solved. The filter has the advantages of being narrow in frequency band, high in quality factor, small in signal deformation after filtering and the like, the adjustable range of the frequency band is further widened by means of the parallel connection design of the capacitors, and the filter can be widely applied to noise filtering of a low-frequency harmonic circuit and a high-precision acquisition circuit.

The invention relates to a maintenance system of a high-efficiency energy-saving power lithium ion battery. The maintenance system of the high-efficiency energy-saving power lithium ion battery comprises a controllable power source, an MOSFET control switch, a PWM isolation drive circuit, a current control circuit, a sampling resistor, a voltage collecting circuit and a current collecting circuit. The positive electrode of the controllable power source, the MOSFET control switch, the power lithium ion battery, the sampling resistor, and the negative electrode of the controllable power source are sequentially in series connection. The voltage collecting circuit is connected to the two ends of the power lithium ion battery in parallel, and the current collecting circuit is connected to the two ends of the power lithium ion battery in parallel. The input end of the current control circuit is connected with the negative electrode of the power lithium ion battery and the output end of the PWM isolation drive circuit respectively, and the output end of the current control circuit is connected with the feedback end of the controllable power source. Compared with the prior art, the maintenance system of the high-efficiency energy-saving power lithium ion battery has the advantages that the purpose that a charging switch power source supplies charging energy of the needed amount is achieved, the phenomenon that supply exceeds demand is avoided, and energy-saving charging is achieved.

The invention discloses a charging device and a charging method. The charging device includes an energy unit, a charging module and a charging interface. The charging module includes a voltage changer and a voltage stabilizing module. The voltage stabilizing module includes an energy storage unit connected with the energy unit electrically; a charge-discharge control switch whose first terminal is connected with the energy storage unit electrically and whose second terminal is connected with the energy unit electrically via a reverse protection diode; a voltage monitoring unit connected with a control terminal of the charge-discharge switch and the energy storage unit electrically and used for controlling the on and off of the charge-discharge control switch based on output voltage values of the energy storage unit.

The invention discloses an instantaneous high-energy drive direct-current servo control device. The device comprises a motor drive and magnetic rotation angle sensing portion, a control circuit portion for controlling motor drive and magnetic rotation angle sensing and a power supply management and conditioning circuit portion for supplying power for the motor drive and magnetic rotation angle sensing portion and the control circuit portion. A motor servo mode of the device is magnetic rotation angle sensing, and the control portion can provide high-accuracy motor control for users by extracting information of a magnetic rotation angle sensor. By the aid of the power supply management and conditioning circuit portion, the motor limit usage mode can be satisfied, and the instantaneous voltage is provided for the motor to meet user special requirements. By means of the device, the market vacancy can be filled, and broad application prospects are provided.

The invention discloses a large-current band-gap reference source. The reference source comprises a mains supply, a step-down rectifying and filtering module, a switch conduction module, an overvoltage protection module, a band-gap reference module and an output voltage module, the mains supply is connected with the step-down rectifying and filtering module, the step-down rectifying and filtering module is connected with the switch conduction module, the switch conduction module is connected with the overvoltage protection module, the overvoltage protection module is connected with the band-gap reference module, and the band-gap reference module is connected with the output voltage module. The reference source has the advantages that the overvoltage protection circuit is additionally arranged, so that the circuit can be disconnected under the overvoltage condition, and safe operation of the circuit is guaranteed; and meanwhile, a potentiometer is additionally arranged at the band-gap reference circuit to change the change between resistance values, so that the purpose of changing the output voltage is achieved.

The invention discloses a novel electronic nose air inlet system. An air storage device comprises a closed container, an air inlet pipe and an air guide pipe, the closed container is provided with twobottle openings, the two bottle openings are each provided with a bottle plug with a hole, one bottle plug stretches into an air inlet pipe, the other bottle plug stretches into the air guide pipe, and the length of the part, stretching into the closed container, of the air inlet pipe is more than half. The air guide pipe only extends into the bottle plug not more than 2cm; an air blowing devicecomprises a three-way pipe, two air blowers and two air blowing outlet pipes; an air chamber comprises a chamber body, two N-way pipes and 2(N-1) gas sensors, one ends of the two N-way pipes are connected with two blast air outlet pipes respectively, the other N-1 ends of the two N-way pipes are each internally provided with one gas sensor, and the number of the gas sensors is 2(N-1). Different gas sensors are arranged to detect the variety of edible oil, the air storage device does not need to be heated, and safety and reliability are achieved.

The invention relates to a water-tank jacket medium forced circulation system of a balcony wall-mounted solar water heater. The water-tank jacket medium forced circulation system comprises a heat collector, a water tank, a medium circulating pump, a medium flow meter, a medium circulating pipeline, a controller, a temperature sensor T1 and a temperature sensor T2; the controller can detect difference between medium temperature and water temperature according to the T1 and the T2 and control the circulating pump to turn on or off; the controller is provided with a PWM (pulse-width modulation) circuit, a flow indicating circuit and a medium level indicating circuit and can control output voltage by changing pulse width, and output frequency is controlled by changing of circles, so that lift and flow of the medium circulating pump can be adjusted as required, and actual flow values of the medium circulating pump can be displayed in a display screen of the controller; four probes are arranged in a jacket of the water tank, and medium level information in the jacket and collected by the probes can be displayed in the display screen of the controller.

The invention discloses a suspension power supply, which comprises a voltage regulation control unit and a voltage regulation unit, and is characterized in that the voltage regulation unit comprises an operational amplifier, a voltage division circuit, a feedback circuit and an adjustment circuit; the voltage division circuit is used for dividing an input voltage, a voltage division point of the voltage division circuit is connected with a first input end of the operational amplifier, an output end of the operational amplifier is connected with the adjusting circuit, the feedback circuit is connected with the adjusting circuit, and a second input end of the operational amplifier is used for accessing a feedback voltage of the feedback circuit; the voltage regulation control unit is connected with the voltage division circuit or the feedback circuit; the voltage regulation control unit is used for regulating the voltage division ratio of the voltage division circuit or the feedback circuit; the adjusting circuit is used for adjusting the input voltage, and the output of the adjusting circuit serves as the output voltage of the suspension power supply.