90results about How to "Constant output power" patented technology

A power management system and method for a wireless communication device generates an average desired transmit power signal based on at least one of a received signal strength indicator signal and a power control instruction signal from a base station. A power supply level adjustment signal is generated based on the data parameters of an outgoing data stream and at least one environmental information signal. A combination of the power supply level adjustment signal and the average desired transmit power or a gain control signal and an altered version of the power supply level adjustment signal is used to generate a variable power supply signal that is provided to an output amplifier block for sufficiently generating outgoing wireless device radio signals while reducing power loss in the output amplifier block.

A PWM controller having frequency jitter includes a modulator for generating a first jitter current and a second jitter current. An oscillator generates a pulse signal for producing a switching frequency in response to the modulation of the first jitter current. An attenuator is connected in a voltage feedback loop for attenuating a feedback signal to an attenuated feedback signal, in which the attenuated feedback signal is utilized to control an on-time of a switching signal. A variable-resistance circuit is connected with the attenuator for programming an attenuation rate of the attenuator in response to the modulation of the second jitter current. The switching frequency increases whenever the first jitter current increases. Meanwhile, the impedance of the attenuator will decreases and the attenuation rate will increase whenever the second jitter current increase. The on-time of the switching signal is thus immediately reduced, which compensates the decrease of the switching period and keeps the output power as a constant.

A device (1) for plasma treatment comprises an electrode (2) having a surface (14) covered by a dielectric barrier (3), and an AC high voltage source (6) for applying an AC high voltage to the electrode (2) to bring about a dielectric barrier discharge (9) in a gas (10) at atmospheric pressure present in front of the dielectric barrier (3) in order to generate a plasma. To the end of generating the plasma even without a counter-electrode for the electrode (2), pointed tips are distributed over the surface (14) of the electrode (2), these pointed tips pointing towards the gas (10) in front of the dielectric barrier (3), whereas the dielectric barrier (3) has a smooth outer surface (15) facing the gas (10).

There is proposed a method and a module for real time control of power per optical channel in a multi-channel optical communication line formed by a group of optical elements connected in a chain by fiber spans. The group of elements comprises one or more optical fiber amplifiers (OFA); each of the spans is characterized by its span loss, while each of the OFA is characterized by its gain and its designed output power per channel. The method comprises steps of calculating an expected total input power value (EIP) for a particular optical amplifier (OFA) in the line, measuring a real total input power (MIP) at the particular optical amplifier, and comparing the values. If a difference between the EIP and the MIP at the OFA exceeds a predetermined value, the method (and the module) ensures adjusting the gain of the OFA to maintain its output power per channel constant.

The present invention particularly discloses a novel feedback circuit, mainly comprising: a signal sampling unit, a feedback unit, a signal concerting unit, and a signal adjusting unit. During the operation of the feedback circuit, a current-mode error amplifier unit is configured to output a current error signal based on a current sampling signal and a dimming signal outputted by the signal converting unit, so as to activate a PWM controlling unit to stabilize an output current of a LED driver circuit. In the meantime, a voltage-mode error amplifier unit cooperates with the PWM controlling unit to adaptively regulate an output voltage of the LED driver circuit based on a voltage sampling signal and an adjustment signal outputted by the signal adjusting unit, in order to facilitate the LED driver circuit provides a constant output power.

The hydraulic empty container piling crane includes walking chassis, operator's cab, gantry and sling. The operator's cab and the gantry are installed on the walking chassis, and the sling is installed onto the gantry. The walking chassis includes chassis frame, engine, hydraulic pump, hydraulic motor, speed reducer, half shaft, wheel mechanism and tyre assembly. The hydraulic pump is connected to the output of the engine and connected via pipeline to at least two hydraulic motors, the hydraulic motor has output connected via the speed reducer to the half shaft, the half shaft is connected via the wheel mechanism to the tyre assembly, and the speed reducer is installed on the chassis frame. The present invention has high work efficiency, convenient operation, low use cost and other advantages.

An electric cooker comprises a pot, a pot cover, an inner pot, a heating device, a control device and a switching power supply. The heating device comprises a relay temperature control mechanism and a thyristor temperature control mechanism. The relay temperature control mechanism comprises a relay and a first heating tube connected with the relay. The thyristor temperature control mechanism comprises a thyristor and a second heating tube controlled by the thyristor. The relay and the thyristor are controlled by the control device. A heating control method includes: setting output power P0; calculating power Pr of the first heating tube under current voltage; calculating difference between P0 and Pr, and converting ratio of the difference to Pt into thyristor-triggered semiwave number; counting the thyristor-triggered semiwave number; and acquiring current required output power. Excessive temperature rising of the thyristor can be avoided.

A radio frequency generator, includes an input voltage unit, a smart power unit, a voltage acquisition unit, a power amplifier unit, an output unit, a load unit, a current acquisition unit, a processor unit, a signal transmission and drive unit and an input control unit. The present application combined advantages of the high-frequency electric knife and the radio frequency ablation device, can be used for both cutting and coagulating the target tissue, and the ablation or treatment to the target tissue. This radio frequency generator has high versatility, can be used as standard component to produce and manufacture. Different medical radio frequency manufacturers can produce and manufacture their own products to meet clinical needs of different clients and different departments for example, by changing a small quantity of peripheral circuits or software.

An input signal having an intermediate signal superposed on a DC voltage is applied to a variable attenuation circuit through an amplifier. An output of the variable attenuation circuit is detected by a detecting circuit. A DC voltage from the detecting circuit is compared with a reference voltage from a reference voltage generating circuit by a comparing circuit. Based on a comparison output, the amount of attenuation of the variable attenuation circuit is controlled, and after the output of the variable attenuation circuit is amplified by an amplifier, it is mixed with a local oscillation signal from a local oscillation circuit at a mixer circuit, converted to a microwave signal, and transmitted.

The invention relates to the technology of ultrasonic power supplies and provides constant-power power supply with a high power factor and fast response to reduce system complexity and improve detection precision. To this end, the invention provides a constant-power driving power supply based on an ARM and a multiplier and a driving method, The constant-power driving power supply comprises a firstpart which is a driving circuit including a DDS chip, an integrated PWM wave control chip and an inversion amplification circuit; a second part which is a sampling matching circuit; a third part which is a signal conditioning circuit; and a fourth part which is a micro-control module formed by an ARM microprocessor and achieving constant-power control by adjusting the frequency and the duty ratioof a PWM wave. The invention is mainly applied to the design and manufacture of ultrasonic power supplies.

An oil pumping unit comprises a main frame, an oil pumping rod, a counter weight, a platform, a motor, a multilevel speed reducer, a rewinding wheel and a guide wheel, wherein the platform is arranged at the top of the main frame, the motor, the multilevel speed reducer and the rewinding wheel are arranged on the platform, and the guide wheel is pivotally mounted on the platform through a guide wheel support. The motor is connected with the rewinding wheel (5) through the multilevel speed reducer to drive the rewinding wheel, and the rewinding wheel is provided with 2n first holes, 2n second holes and 2m spiral grooves, wherein the first holes are used for a hauling cable of the counter weight, and the second holes are used for a suspension cable of the oil pumping rod. Positions and numbers of the spiral grooves, the first holes and the second holes are configured to enable the suspension cable of the oil pumping rod and/or the hauling cable of the counter weight to be wound in the spiral grooves in a mutual noninterference manner during operation and constantly be opposite in rewinding force moment. The oil pumping unit has the advantages of evident energy saving effect, compact structure and convenience in maintenance. A control system and a control method which are suitable for the oil pumping unit are further provided.

The invention relates to the technical field of medical treatment, in particular to a method and application of a semiconductor laser therapeutic instrument. The semiconductor laser therapeutic instrument is characterized in that a power-on key, a power-off key, a power selection key, a therapeutic opening key, a power indicating lamp, a therapeutic indicating lamp and a cell box are arranged on a shell; a micro-processing control circuit, a charging control circuit and a laser driving circuit are arranged in the shell; and the output end of a resistor R37 of the laser driving circuit, the collecting electrode of a triode Q31 and the port 10 of an operational amplifier U30 are respectively connected to a laser transmitter through three-core silk-covered wires. Compared with the prior art, the invention has the following advantages that: the semiconductor laser therapeutic instrument is managed with low power consumption, has an automatic power-off function and is in a low power consumption state after being powered off, and simultaneously, a system for power supply is switched to an external adapter for power supply during charging; and a constant-power regulating circuit regulates the output power by the unprocessed generated control signal to monitor the laser output power, and a negative feedback control mode is adopted, thereby achieving the constant output power.

The invention discloses a hydrogen fuel cell power system for a forklift. The hydrogen fuel cell power system comprises a system frame, an electric pile, a lithium battery system and a hydrogen storage system; a partition plate is horizontally arranged in the system frame; the system frame is divided into an upper-layer space and a lower-layer space through the partition plate; and the lithium battery system and the hydrogen storage system are both installed in the lower-layer space. Hydrogen is stored through a hydrogen storage bottle, input and output are controlled through a bottle valve assembly, the bottle valve assembly conveys the hydrogen into a fuel cell stack for reaction, after electric energy is generated, the electric energy is adjusted to a voltage plateau required by a vehicle through a step-down DCDC, and the electric energy generated by the fuel cell stack can be directly output to a motor of the whole vehicle, and the electric energy can be also output to a lithium battery pack to be stored, and then the lithium battery pack supplies power to the motor of the electric forklift. The forklift power supply system can provide continuous output power of 5kW and peak output power of 35kW for the whole forklift, and meets the use requirements of most of 1-2.5 ton counterbalance forklifts. In the working process of the forklift, the performance of the whole forklift cannot be affected along with reduction of the stored energy.

The invention discloses a constant-power load control method and circuit applied to a DC-DC converter, and the method comprises the steps: 1) respectively sampling an output voltage and an inductive current through a voltage sampling module and a current sampling module, and inputting the sampled signal into an ADC module; 2) converting the input sampled signal into a digital signal through an ADCmodule, and inputting the digital signal into a correction module; 3) comparing the digital signal with a prediction value obtained by solving a prediction model by using a correction module, and employing the difference value as a correction signal to be input into an MLD-MPC control module; and 4) solving the control model by using the MLD-MPC control module according to the correction signal,and achieving the constant power load control of the DC-DC converter according to the calculated switch duty ratio. According to the invention, the problems of steady-state error, poor dynamic performance and the like of a traditional constant power control method are solved, so that the DC-DC converter can quickly and stably adjust and maintain constant power output when facing disturbance suchas input voltage jump, load jump and the like.

The invention provides a broadband microwave photon phase shifter with constant output power. The phase shifter can realize the function of continuously shifting the phase of a high-frequency broadband microwave signal in a range greater than 360 degrees under a single compact micro-ring structure, and reduces the tuning difficulty; meanwhile, the output microwave signal power in the phase shifting process can be kept constant, so that the practicability is improved; and the upper limit of the working frequency of the phase shifter is only determined by the bandwidth of the detector and the free spectral region range of the phase shifter, and the working bandwidth is large. Besides, a tunable laser does not need to be used, the relative position of the optical carrier signal in a resonance spectrum can be changed only by changing the resonant wavelength of the resonator through thermo-optical modulation, the phase shifting function is achieved, and the cost can be reduced.

The invention discloses a dynamic wireless electric energy constant power output system and an equivalent resistance control method thereof and relates to the technical field of dynamic wireless electric energy transmission. The system comprises a transmitting end and a receiving end, wherein the transmitting end comprises a transmitting coil Lp; the receiving end comprises a secondary side assembly 1 and a secondary side assembly 2 which are connected with a load R; the secondary side assembly 1 comprises a receiving coil Ls1 parallel to the transmitting coil Lp; the secondary side assembly 2comprises a receiving coil Ls2 parallel to the transmitting coil Lp; the receiving coil Ls1 and the receiving coil Ls2 each comprise a square coil with a side length of L; the transmitting coil Lp comprises a plurality of square coils with the side length of L in cascade connection; the receiving coil Ls1 and the receiving coil Ls2 are overlapped to form a secondary side coil assembly, and the length of the overlapped part is L/2. According to the system disclosed by the invention, the total power is averagely distributed in the receiving end of the secondary side assembly 1 and the receivingend of the secondary side assembly 2 in a moving process, voltage-current stress of a switching tube can be decreased, and constant output power of the system is ensured.

The invention provides a tandem ribbon heater, which comprises core wires, an insulating layer, an inner sheath layer, a rubber framework, reinforcing ribs, a filling layer, a shielding layer, an outer sheath layer, a reinforcing layer and metal wires. According to the tandem ribbon heater, the resistance and the passing current per unit length of the core wires are constant, so that the head andthe tail of the whole ribbon heater are uniform in heating, the output power is constant, and the use length is long. In addition, the tandem ribbon heater is internally provided with the rubber framework, the reinforcing ribs and the metal wires, so that the firmness of a heat tracing band can be better ensured, the core wires inside are not exposed by bending, the safety in use is ensured, and the service life is prolonged.