39results about How to "Large power adjustment range" patented technology

The invention discloses a digital power control circuit, which is applied to an class E power amplifier with low power output, and comprises a stage matching circuit and an output amplifier stage, wherein, the stage matching circuit is used for effective cascade of an amplifier, and the output amplifier stage is used for amplifying signal power. An output terminal of the stage matching circuit is connected with an input terminal of the output amplifier stage; a controllable amplifier stage used for pre-magnification function and signal amplitude gain control is connected with the input terminal of the stage matching circuit, and the input terminal of the stage matching circuit is connected with the output terminal of the controllable amplifier stage; the input terminal of the output amplifier stage is connected with a bias control circuit used for adjusting the grid bias voltage entering a switching transistor of the output amplifier stage; and the input terminal of the output amplifier stage is connected with the output terminal of the bias control circuit through an inductor. The digital power control circuit increases the output power range and output power efficiency, and has the advantages of simple and reliable circuit organization and easy integration of monolithic circuits.

The invention discloses a circuit and a method for a resonant network, and specifically discloses a power conversion circuit. The power conversion circuit comprises a square wave generator, a resonant network, a transformer and a controller. The square wave generator is used for generating a square wave power. The resonant network is used for receiving the square wave power and outputting a first resonance power. The resonant network is composed of a capacitor, an inductor and a controllable capacitive device. The transformer is connected with the controllable capacitive device, and is used for receiving the first resonance power and outputting a second resonance power. The second resonance power after rectification is supplied to a load. The controller is used for generating an on-off signal based on the result of comparison between a threshold signal and a signal calculated according to at least one detection signal of the load, and supplying the on-off signal to the controllable capacitive device.

The invention discloses a divergent porous medium burner. The burner comprises a shell, a porous medium and baffle bricks. The burning end of the shell is of a cone structure or a tetragonal pyramid structure. The air inlet end of the shell is of a cylinder structure or a tetragonal prism structure. The porous medium is charged into a burning end shell body of the shell. The baffle bricks are located between the porous medium and the air inlet end of the shell. An air inlet is formed in the shell side wall of the air inlet end of the shell. A fuel gas inlet is formed in the wall surface of theshell axis end of the air inlet end of the shell. The gas inlet direction of the fuel gas inlet is perpendicular to the air inlet direction of the air inlet. The taper range of the burning end of theshell is 0-45 degrees. The porous medium has four charging modes including the uniform charging mode, the axial step charging mode, the radial step charging mode and the axial tapered charging mode.By means of the divergent porous medium burner provided by the invention, the phenomena that flames are not uniformly distributed and are unstable can be effectively avoided, and the burner has the characteristics of large power regulating range, more thorough burning and higher burning efficiency.

The invention discloses a nuclear reactor and solar energy photo-thermal power generation combined system which comprises a first circulation loop, a second circulation loop and a third circulation loop. The first circulation loop is provided with a nuclear reactor and a heat exchanger. Heat generated by the nuclear reactor is transmitted into the heat exchanger through a circulation pipeline on the first circulation loop. A solar heat collecting module and a steam generator are arranged on the second circulation loop. Heat generated by the solar heat collecting module and the nuclear reactoris transmitted to the steam generator through the second circulation loop to generate steam, and the steam is conveyed to a steam drive turbine on the third circulation loop. The steam drive turbine drives a power generator to generate power. By means of the nuclear reactor and solar energy photo-thermal power generation combined system, the nuclear reactor is combined with solar photo-thermal power generation, the nuclear reactor and solar energy photo-thermal power generation combined system is formed, the problem that solar energy photo-thermal power generation cannot be achieved at night,and consequently a unit is frequently started and stopped is solved, and the solar energy photo-thermal power generation stability is improved.

The invention discloses a high-efficiency variable gain E-type radio frequency power amplifier which comprises a controllable amplifier stage. The controllable amplifier stage is connected at an input end of an interstage matching circuit and is used for pre-expanding control of function and signal amplitude gain. The input end of the interstage matching circuit is connected with an output end of the controllable amplifier stage. An input end of an output amplifier stage is connected with a bias control circuit which is used for adjusting grid electrode bias voltage entering a switch transistor of the output amplifier stage. The input end of the output amplifier stage is connected with an output end of the bias control circuit through an inductor. According to the high-efficiency variable gain E-type radio frequency power amplifier, signal amplitude and a duty ratio control method are combined, and the purpose of control of output power of the nonlinear E-type power amplifier is achieved. Compared with an original E-type power amplifier power control method, output power range and output power efficiency are improved obviously.

The invention relates to a multi-channel broadband power-digitally-adjustable frequency conversion system and a control method thereof. The system comprises an FPGA chip, a direct digital frequency synthesizer, a mixer, a switch filter assembly, a temperature compensation attenuator, a first amplifier and a multi-channel power adjustable module. The input end of the direct digital frequency synthesizer is connected with a reference frequency; the output end is connected with the input end of the mixer; the output end of the mixer is connected with the input end of the temperature compensationattenuator through the switch filter assembly. The output end of the temperature compensation attenuator is connected with the input end of the multi-channel power adjustable module through the firstamplifier. The output end of the multi-channel power adjustable module is a radio frequency output end, and the direct digital frequency synthesizer, the frequency mixer, the switch filter assembly and the SPI communication interface of the multi-channel power adjustable module are connected with the I/O port of the FPGA. According to the system, the number of control ports can be reduced, multi-channel radio frequency output can be realized, the channels are mutually independent, the power regulation range is large, the power attenuation can be digitally and accurately controlled, and good spurious suppression is achieved.

The invention relates to an application method of a thermal power flexibility multi-source coordination'active balance 'process system, which is characterized by comprising the following steps of: setting a thermal power flexibility multi-source coordination'active balance service' process system which comprises a flywheel energy storage frequency modulation system, a fused salt energy storage frequency modulation system and a thermal power flexibility'active balance 'process monitoring control system; controlling a flywheel energy storage frequency modulation system to provide rotational inertia or primary frequency modulation active balance service of the thermal power plant; a flywheel energy storage frequency modulation system and a fused salt energy storage frequency modulation system are fused with a thermal power generating unit to form a virtual frequency modulation power supply so as to provide a multi-source coordination active balance service. The method can be widely applied to the technical field of active balance service of thermal power flexibility transformation.

The invention relates to a digital constant-power high-voltage plasma power supply which comprises an electromagnetic interference filter circuit, a soft start circuit, a single-phase rectification circuit, a filter energy storage circuit, a full-bridge circuit, an LLCC resonance circuit, a power voltage sampling circuit, a power current sampling circuit, a digital control circuit, an MOSFET drive circuit and an RS485 communication circuit. An input voltage is connected with the single-phase rectifier circuit through the electromagnetic interference filter circuit, forms a direct current voltage through the filter energy storage circuit, is connected to the full-bridge circuit for chopping, then is connected to the LLCC resonance circuit for oscillation filtering, and is subsequently connected to the high-voltage transformer for output; the soft starting circuit is connected to the single-phase rectifying circuit, the power voltage sampling circuit and the power current sampling circuit are connected to the digital control circuit to provide closed-loop sampling calculation parameters, and the digital control circuit is connected to the full-bridge circuit through the MOSFET driving circuit and connected to the RS485 communication circuit.

The invention discloses an I-shaped self-preheating burner with a grading function. The I-shaped self-preheating burner with the grading function is characterized in that a heat exchange cylinder sleeves an inner pipe; spray holes are distributed at the head end of the heat exchange cylinder; the tail end of the heat exchange cylinder is opened; the head end of the inner pipe is hermetically connected to the inner side of the head end of the heat exchange cylinder; the tail end of the inner pipe is closed; a grading ring slidably sleeves the inner pipe; the head end of the grading ring is located in an annular space between the tail end of the heat exchange cylinder and the inner pipe; an operating component at the tail end of the grading ring hermetically extends out of a shell; a combustion chamber is located in the head end of the inner pipe and hermetically penetrates out of the heat exchange cylinder; a central pipe hermetically penetrates into the inner pipe and extends to the head end of the combustion chamber; a grading pipe sleeves the central pipe; the head end of the grading pipe extends into the combustion chamber; the tail end of the grading pipe is hermetically mounted on the shell; an ignition electrode hermetically penetrates through the shell and extends into the inner pipe to enter the combustion chamber; a coal gas inlet, an air inlet and a smoke outlet are formed in the shell; the coal gas inlet communicates to an annular space between the tail end of the grading pipe and the central pipe; and a communication hole is formed in the side face near the tailend of the inner pipe. According to the burner, grading combustion in a high-temperature mode and a low-temperature mode is achieved, and NOx generation is reduced.

The invention discloses an electric heating control circuit for an air resistance furnace. The electric heating control circuit is composed of four stage heating control circuits, a main switch and a main control circuit. In the four stage heating control circuits, a first stage heating control circuit is used for controlling an air preheating section of the air resistance furnace, and a controlled electric heating element is arranged at the front end of the air resistance furnace and close to an air inlet; an electric heating element controlled by a fourth stage heating control circuit is arranged at the position close to an air outlet; and electric heating elements controlled by second and third stage heating control circuits are arranged between the first stage heating control circuit and the fourth stage heating control circuit. An external alternating current power supply is accessed through the main switch, and the four stage heating control circuits are arranged at the lower end of the main switch; and the four stage heating control circuits are connected with the main control circuit which sends drive signals and temperature setting signals to control the four stage heating control circuits.

The invention relates to the technical field of metallurgy, in particular to a flat-flame nozzle with an automatic ignition and flame detection device. The flat-flame nozzle with the automatic ignition and flame detection device comprises nozzle bricks, wherein the nozzle bricks are connected with an air pipeline shell; the air pipeline shell is connected with a gas pipeline shell; gas core tubes are extended into spray orifices in the nozzle bricks and are fixedly welded with a gas nozzle flame holder; an air distribution plate is sleeved on the gas nozzle flame holder; an air inlet is formed on the air pipeline shell and is connected with an air pipeline; the gas pipeline shell is connected to a gas pipeline; electrodes are plugged into two electrode holes and electrically connected with a flyback transformer, and the flyback transformer is electrically connected with a controller; and the electrodes are electrically connected to a detection port of the controller, and an electromagnetic valve of the gas pipeline is electrically connected with the controller. By adding the functions of automatic ignition and flame detection, on-off control is realized, and pulse control is realized for a burning system with the flat-flame nozzle; stable and explanate flame is formed, so that the uniformity of temperature of a hearth is ensured; and therefore, the flat-flame nozzle is simple and compact in structure and can be widely applied.