34results about How to "Duty cycle regulation" patented technology

The solution method for preparing metal photonic crystal belongs to the technical field of nano photoelectron materials and devices thereof. The existing method for preparing metal photonic crystal is faced with the problems such as high cost, low efficiency and small area of preparation, etc. In the invention, sequentially, optical resist is rotatably coated on a substrate; the interference photolithography is adopted to prepare one-dimensional or two-dimensional nano optical grating structures; metal nano particle sol is rotatably coated and goes through low temperature heat treatment, thusobtaining the metal photonic crystal. The invention has the advantages of low cost, high efficiency and preparation of the metal photonic crystal in a large acreage and the like.

The invention relates to a charge control circuit of multiple lithium batteries. The charge control circuit comprises a DC / DC conversion module, a battery pack module, a driving circuit module, a constant-voltage control module, a constant-current control module, a microprocessor module and a feedback circuit module. The input control end of the constant-voltage control module is connected with a charger interface, the input control end of the constant-current control module is connected to the corresponding pin of the microprocessor module, the feedback circuit module is connected between the negative electrode of the battery pack and the corresponding pin of the microprocessor module, and the input control end of the driving circuit module is connected with the corresponding pin of the microprocessor module, the output end of the constant-voltage control module and the output end of the constant-current control module. The invention further relates to a charge control method of the multiple lithium batteries and a general type charger. The stability is improved, and the control precision of the circuit is improved; intelligent control is achieved, the integrated degree is high, the structure of the circuit is simplified, and the production cost is controlled; the feedback speed of a microprocessor is high, real-time feedback is guaranteed, and fluctuations are reduced.

A PWM circuit duty ratio adjustment method and system for a blood pressure measurement apparatus. The PWM circuit duty ratio adjustment method for a blood pressure measurement apparatus comprises the following steps: when a blood pressure measurement apparatus is used, acquiring a real-time atmospheric pressure in a cuff (S10); calculating a duty ratio of a PWM circuit in the blood pressure measurement apparatus according to the real-time atmospheric pressure and a duty ratio-atmospheric pressure relation model (S20), wherein the duty ratio-atmospheric pressure relation model represents a functional relation between the duty ratio and the atmospheric pressure when a rising velocity of the atmospheric pressure in the cuff is constant; and adjusting a working duty ratio of the PWM circuit according to the duty ratio (S30). The PWM circuit duty ratio adjustment method and system for a blood pressure measurement apparatus are applicable to various kinds or types of blood pressure measurement apparatuses, have a relatively high adjustment effect, and ensure the working stability of a PWM circuit.

The present invention provides a photovoltaic solar energy system, a control method thereof, and a computer-readable storage medium. The method includes acquiring the output power and sampling current of the current sampling period and the previous sampling period, and obtaining the output power and sampling current of the current sampling period and the previous sampling period according to the output of the current sampling period and the previous sampling period. Power and sampling current determine whether the working environment is a multi-power extreme value environment; if it is confirmed that the current working environment is a multi-power extreme value environment, change the duty cycle of the pulse modulation signal by the preset first step length, and calculate each The output power corresponding to the duty cycle is searched for the target duty cycle of the pulse modulation signal corresponding to the maximum output power, and the duty cycle of the pulse modulation signal output by the DC converter is adjusted to the target duty cycle. The present invention also provides a photovoltaic solar energy system and a computer-readable storage medium implementing the above method. The invention can quickly find the duty ratio corresponding to the pulse modulation signal corresponding to the maximum output power, and can reduce the production cost of the photovoltaic solar energy system.

The invention discloses a duty ratio adjusting circuit and an implementation method thereof. The duty ratio adjusting circuit comprises a DC bias voltage adjusting circuit used for converting a digitalized input clock signal CLK _ in into a DC bias voltage controlled clock; a phase inverter used for converting the DC bias voltage controlled clock into a digitalized clock signal CLK _ out; a control voltage generation circuit used for generating a control voltage under the control of high and low levels of the output clock signal CLK _ out, wherein the control voltage is connected to the DC bias voltage adjusting circuit to adjust the DC bias voltage of the DC bias voltage controlled clock output by the DC bias voltage adjusting circuit. By adoption of the duty ratio adjusting circuit, the duty ratio adjusting circuit capable of adjusting the duty ratio of signals to 50% is realized.

The invention relates to a driving method of a switch tube control pulse. The digital control chip of the present invention divides the target pulse control signal into two control signals with equal pulse width, and the output of the digital control chip is respectively connected to the inversion totem pole, and then respectively connected to the two ends of the primary winding of the pulse transformer through the inversion totem pole , a group of different terminals on the secondary side of the pulse transformer are connected as the ground of the output drive, and the other group of different terminals are respectively connected to the anodes of the two diodes, and the signal after the two cathodes are connected is then connected to the voltage dividing resistor for voltage division. Connect to the input terminal of the driver chip, and the output of the driver chip is connected to the gate current limiting resistor of the switch tube in the power circuit. The invention overcomes the defect that the traditional electromagnetic isolation driving and photoelectric isolation driving methods are not easy to be used for high frequency and high power density power converters. The invention has fast response speed, high insulation strength between the primary side and the secondary side, strong common-mode interference suppression ability, and eliminates the limitation of the duty ratio caused by the need for magnetic recovery on the primary side of the pulse transformer.

The present invention relates to the technical field of servo motor control, in particular to a servo motor voltage control method, comprising the following steps: S1: collecting the current working voltage of the servo motor through a controller; when the collected working voltage is within a set range, Repeat step S1, and when the collected operating voltage exceeds the set range, execute step S2; S2: Use a phase-shifted full-bridge circuit to adjust the input voltage of the servo motor, and repeat step S1 after each adjustment is completed; The controller keeps the preset duration of each power-on of the transformer in the phase-shifted full-bridge circuit unchanged, and realizes the adjustment of the duty cycle of the preset duration when the transformer is powered on by changing the frequency of the control signal of the phase-shifted full-bridge circuit, so as to realize the work voltage regulation. The invention can timely and effectively control the whole working process of the servo motor, adopts the frequency conversion control method, improves the stability of the output voltage, and prolongs the service life of the motor.

The invention provides a self-excitation-reinforcing high-voltage conversion system of a switch reluctance generator. The system is composed of three conversion branches and an isolation and voltage-down DC / DC converter. The input ends of the three conversion branches are connected in parallel, the output ends of the three conversion branches are connected in series, thus, higher voltage output isobtained, excitation reinforced parts are distributed in all the conversion branches where all phases of windings are located respectively, independent excitation power sources are omitted, the system reliability is improved, and the advantages of a switch reluctance motor are effectively utilized. As input end voltages are far lower than output end series total voltages, voltage withstanding ofinternal devices is low, meanwhile, the switching frequency of all switching tubes is within a low-and-medium frequency range, and losses are low. The system is very suitable for converters of all switch reluctance generators, and especially is oriented to high-voltage loads or grid-connection requirements.

The invention discloses a noise control method and system for an electromagnetic valve and an air conditioner, relates to the field of noise reduction control of air conditioner electromagnetic valves and aim at solving the problem that when a current air conditioner switch component is switched off or switched on, great noise is generated, and use of a user is affected. The critical voltage duty ratio of the electromagnetic force in the electromagnetic valve is detected when the balance state of a metal bolt is maintained; whether a switch controller sends switching-off or switching-on signals to the electromagnetic valve or not is detected; and the duty ratio of the control signals in the switching-off or switching-on process of the electromagnetic valve is adjusted in a segmented manner according to the critical voltage duty ratio. According to the noise control method and system for the electromagnetic valve and the air conditioner, the duty ratio of the control signals is adjusted in the switching-on and switching-off processes of the electromagnetic valve so that the jumping changing type of currents in an electromagnetic valve coil is transformed into a gradually and gently changing type, and therefore the electromagnetic force can be gently changed, impulsion is reduced, and the sounds generated by collisions are effectively lowered.

A control method for reducing current fluctuations of switched reluctance motors under current chopping control, suitable for switched reluctance motors with various phase numbers and structures under the non-inductive model, according to the position sensor signal, a conduction period is divided into Commutation section and separate conduction section; the given current determined according to the given speed and the actual speed of the motor calculated by the position sensor; the winding current of each phase is collected by the Hall current sensor; The actual current of the phase segment and the individual conduction segment adjusts the PWM duty cycle of the commutation segment and the individual conduction segment respectively; the input of the controller is the speed difference, the actual current of the winding, and the position signal, and the output is the PWM duty cycle. In this way, the control of the power converter is realized, and the power converter controls the power on and off of the switched reluctance motor to control the motor speed. The invention improves the steady-state characteristics of the switched reluctance motor, increases the steady-state operation efficiency, and reduces the output torque ripple of the motor.