314 results about "Harmonic control" patented technology

A dual, counter-rotating, coaxial rotor system provides individual control of an upper rotor system and a lower rotor system. The lower rotor control system and the upper rotor control system provide six controls or “knobs” to minimize or theoretically eliminate airframe vibration. In a dual, counter-rotating, coaxial rotor system, application of a HHC system to the two rotor systems individually but located on the common axis, will yield essentially complete vibration reduction because the 6 controls will suppress the 6 loads.

The invention relates to an open winding type permanent magnet motor driven reconstructed vehicle-mounted charging system for an electric vehicle. The system comprises a single-phase AC power supply,a rectifier bridge, an input filtering capacitor, three-phase voltage inverters, a three-phase permanent magnet motor winding, an output filtering capacitor, a storage battery and mode switches. The charging system sufficiently utilizes original double three-phase inverters, the permanent magnet motor winding, control and sensor units and the like of electric vehicles, and total integration of functions such as motor driving, high-power factor charging, harmonic control and the like is realized by optimizing topology to complete rectification, inversion and power factor correction. During charging, two three-phase voltage inverters are reconstructed into a three-phase cascading Buck-Boost circuit; the permanent magnet motor winding serves as an energy storage inductor of the three-phase cascading Buck-Boost circuit. By means of the charging system, the cost of a device can be effectively reduced and high-power factor charging can be realized.

The invention discloses a high-efficiency class-F and inverse class-F power amplifier. A transistor, a parasitic compensation circuit, a harmonic control circuit and an output fundamental wave impedance matching circuit are included. The harmonic control circuit is located between the parasitic compensation circuit and the output fundamental wave impedance matching circuit, and the parasitic compensation circuit is located between the transistor and the harmonic control circuit. As for a fixed work frequency, the input end of the harmonic control circuit forms a second harmonic short dot and a third harmonic open-circuit dot, the harmonic control circuit is composed of three micro-strips, and the parasitic compensation circuit is composed of an L-type micro-strip structure. A parasitic component compensation function can be achieved by adjusting electric length parameters of a micro-strip in the parasitic compensation circuit, and meanwhile drain electrode impedance conditions of the class-F and inverse class-F power amplifier can be achieved. By means of the class-F and inverse class-F power amplifier, influences of the parasitic component on the harmonic control circuit can be effectively reduced, precise control of second harmonics and the third harmonics is achieved, and work efficiency of the power amplifier is improved.

A method of processing an audio signal is disclosed. The present invention includes receiving, by an audio processing apparatus, an input signal; extracting a low frequency signal, a mid frequency signal and a high frequency signal from the input signal; obtaining at least one of a low-band gain and a harmonic control factor, based on a loudspeaker characteristic; obtaining mid-band gain based on the loudspeaker characteristic; generating a modified low frequency signal by applying the low-band gain to the low frequency signal; when the harmonic control factor is obtained, generating a harmonic signal from the modified low frequency signal using the harmonic control factor, generating a modified mid frequency signal by applying the mid-band gain to the mid frequency signal; and, generating a mixed signal by mixing the modified mid frequency signal, the high frequency signal, and at least one of the modified low frequency signal and the harmonic signal.

A rotorcraft control system for effectuating primary flight control and high harmonic control. The control system preferably including at least one primary flap, at least one primary actuator used principally for primary flight control, at least one secondary flap, and at least one secondary actuator used principally for high harmonic control. The at least one secondary flap and the at least one secondary actuator preferably may also be used to enhance primary flight control under some flight conditions.

A rotary wing aircraft is provided including a dual counter-rotating, coaxial rotor system having an upper rotor system and a lower rotor system rotatable about a common axis. A plurality of blade assemblies is mounted to a portion of either the upper rotor system or the lower rotor system. A plurality of individually controllable actuators is coupled to each of the plurality of blade assemblies. Each of the plurality of actuators is configured to control movement of the coupled blade assembly about a pitch axis. The rotary-wing aircraft additionally includes a sensor system within an airframe. A higher harmonic control (HHC) controller is arranged in communication with the sensor system and the plurality of actuators to individually control the upper rotor system and the lower rotor system to reduce vibration.

The invention discloses a reverse F-type power amplifier and an emitter as well as a processing method. The main contents are that the reverse F-type power amplifier comprises a power amplifying part, and a harmonic wave control circuit comprising a third harmonic wave short-circuit circuit and a second harmonic wave open-circuit circuit; after being amplified by the power amplifier, the input radio frequency signal is input to the harmonic wave control circuit through the input end of the harmonic wave control circuit; in the harmonic control circuit, the input radio frequency signal passes by the third harmonic wave short-circuit circuit and the second open-circuit circuit in sequence, and is output by the output end of the harmonic wave control circuit; and the linear effect of an impedance micro-strip on the radio frequency is reduced, the non-linear feature of the power amplifier is effectively corrected, the effect on VBW (Video Band Width) of the power amplifier caused by the inductive effect of the impedance micro-strip in the prior art is effectively reduced, and the linear effect of the radio frequency signal amplified by the power amplifier is improved.

The invention discloses an inverse class-F power amplifier, which comprises a transistor, a parasitic compensation circuit, an output end harmonic control circuit and an output end fundamental wave impedance matching circuit, wherein the output end harmonic control circuit is positioned between the output pin of the transistor and the output end fundamental wave impedance matching circuit; the parasitic compensation circuit is positioned in the output end harmonic control circuit, and comprises at least two sections of stepped impedance microstrips which are connected in series; and short-circuit points and/or open circuit points with secondary to quintuple harmonic frequency are formed at the tail ends of the stepped impedance microstrips. The inverse class-F power amplifier provided by the invention can effectively reduce the influence of parasitic components on a harmonic control circuit, so the working efficiency of the power amplifier can be improved.

The invention discloses a method for designing an LCL (Logical Connection Layer) filter by uniformly controlling photovoltaic grid connection and active power filtering. The method comprises the following steps of: (1) determining the total inductance value LT of the LCL filter; (2) determining the filtering capacitance value Cf of the LCL filter; and (3) determining the resonance frequency fres of the LCL filter. According to the method, the LCL filter is designed on the basis of uniform control over a photovoltaic grid-connected system and active power filtering by using power grid accessing current which is provided with fundamental waves and resonant waves under the comprehensive consideration of the restraint conditions of the control applications of the fundamental waves and the resonant waves; and as proved by verification, the LCL filter can be used for effectively restraining switching frequency and higher-order harmonics, a satisfied photovoltaic grid connection effect can be achieved in combination with modeling control, and idle work required by a power grid is compensated properly.

The invention relates to an island microgrid multi-inverter control system with an active filtering function and a working method thereof. The island microgrid multi-inverter control system comprises a plurality of parallelly-connected inverters and linear and nonlinear loads. The working method includes the steps of harmonic extraction, active harmonic control, power droop control and voltage and current control. The island microgrid multi-inverter control system provides energy to the loads; if harmonic distortion rate of voltage and current of a microgrid common bus is overlarge, the inverters start an auxiliary function of active filtering; if the harmonic distortion rate of voltage and current of the microgrid common bus is within a reasonable range, the inverters cut off the auxiliary function of active filtering; start and cut-off of the active filtering auxiliary function of the inverters are completed seamlessly. The island microgrid multi-inverter control system has the active filtering function, so that harmonic current distortion rate and harmonic voltage distortion rate of the island microgrid common bus are lowered, and stability of voltage of a microgrid is guaranteed; spare capacity of active filtering equipment of the microgrid is reduced, and designing cost of a microgrid system is lowered.

A controller applies a pattern of pulses to switching elements within a multi-level controller to effectuate control of the fundamental voltage magnitude and phase associated with the converter, as well as providing harmonic minimization of the 5^th and 7^th level harmonics. The controller combines a first pattern of pulses with a second pattern of pulses phase shifted by an amount based on the desired fundamental voltage magnitude to create a third pattern of pulses. The controller applies a phase shift to the third pattern of pulses based on the desired fundamental voltage phase. The controller supplies switching control waveforms to active components within the multi-level controller based on the phase shifted third pattern of pulses such that the desired fundamental voltage magnitude and phase is generated and selected harmonics are minimized.

The invention discloses a broadband highly efficient continuous inverse class-F power amplifier and a design method of the continuous inverse class-F power amplifier. The power amplifier comprises five high-low impedance transmission line type input matching circuits, six high-low impedance transmission line type output matching circuits, an adjustable input feed network and a broadband output feed network. Based on the improved simple real frequency technique matching algorithm with harmonic control, the input and output impedance of the power amplifier is subjected to broadband matching, and the high-efficiency working of the broadband highly efficient continuous inverse class-F power amplifier is realized. The design method improves the efficiency, while the defect that the dielectric constant of a baseplate material in the general low-pass filter prototype design method is limited is avoided, and the continuous inverse class-F power amplifier which can be applied to plates with the higher dielectric constant is provided. Under the application background of high-efficiency broadband power amplifiers and aiming at the comprehensive demands of the broadband high-efficiency design method, the broadband highly efficient continuous inverse class-F power amplifier has the advantages of being simple in structure, compact in size and wide in applicability.

A novel circuit scheme and control includes a plurality of identical DC-DC converters with an optimal modulation/harmonic controller and a load balancing portion or process in an integral and systematic design methodology. The modulation/harmonic controller can be configured to control the individual modules in an optimal and coordinated way in the time domain so as to substantially reduce or eliminate a large amount of high-frequency input current harmonics, thus reducing EMI, weight, and size and increasing redundancy. The load balancing portion or process can balance the loads on the converters in real time or offline.

The invention provides an alternating-current to direct-current converter and a control circuit thereof. The control circuit comprises a power control circuit and a square wave generator, wherein the power control circuit is used for comparing an input current sensing signal generated by one input current of the alternating-current to direct-current converter with a frequency modulation control signal generated by a power level control input, and the frequency modulation control signal is also used for the output power control of the alternating-current to direct-current converter and the harmonic control of the input current; and the square wave generator is connected to the power control circuit and generates a driving signal for driving the switching circuit of the alternating-current to direct-current converter according to the frequency modulation control signal, the frequency of the driving signal changes with the frequency modulation control signal, therefore the harmonic noise of the input current of the alternating-current to direct-current converter is eliminated, the switching frequency of a switch is adjusted and the output power of the alternating-current to direct-current converter is adjusted at the same time.

The invention discloses a fully active harmonic control device combining the full compensation and fractionated compensation of a plurality of machines. A full compensation unit is used for compensating for high-band harmonics comprising high-frequency ripple current injected into a power grid by a low-band power unit. A fractionated compensation unit is used for compensating for harmonics of given low bands. The multiple running of power units of compensation groups of the same band improves harmonic compensation accuracy. The switching frequency and compensating capacity of the power unit are inversely proportional, so the finite compensating capacity of the power unit can be maximized by the compensation scheme. By the device, current detection is performed at both a power grid side and a load side, a master controller is used for the operation and distribution of compensation command current, and each slave controller is used for closed loop control over the compensating current of the power unit. The device can compensate for the harmonics of given orders and higher harmonics, and simultaneously has quick response, relatively higher compensation accuracy, high feasibility and high practical value.

The invention is applicable to the field of radio frequency communication, and provides a harmonic power amplifying circuit with high efficiency and a wide bandwidth and a radio frequency power amplifier. The circuit comprises an input matching network, a transistor and an output matching network; a grid electrode of the transistor is connected with an output end of the input matching network, a drain electrode of the transistor is connected with an input end of the output matching network, and a source electrode of the transistor is grounded; the output matching network causes a lower sideband of the harmonic power amplifying circuit to work in a continuous inverse F amplification mode and causes an upper sideband of the harmonic power amplifying circuit to work in a continuous F amplification mode; and the output matching network and a parasitic network of the transistor form a low pass filter. According to the harmonic power amplifying circuit provided by the invention, due to the transition from the continuous inverse F power amplifier working mode to the continuous F power amplifier working mode, the efficiency of a continuous harmonic control power amplifier is effectively improved to be higher than 60%, a relative bandwidth is improved to be higher than 80%, and the harmonic impedance is simple to match and easy to realize.

The invention discloses a unit module of a telescopic soft body robot. Each unit module comprises a steering driving mechanism, a wrist joint moving mechanism, a driving cable assembly and a communication cable assembly, wherein the steering driving mechanism realizes the extension degrees of freedom of the unit modules, and the wrist joint moving mechanism realizes twisting and bending of the unit modules, so that each unit module has five degrees of freedom and excellent flexibility; and the driving cable assembly and the communication cable assembly relieve loads of the unit modules, and meanwhile, realize the signal transfer and the electric driving guarantee. The unit module of the telescopic soft body robot can realize improvement of the loading capacity of single module and the linear displacement increasing function of single module, realizes extension or bending in any direction of the steering mechanism through harmonic control of four driving ropes, and increases the working space of the robot; and in addition, multiple modules are connected with a reconstructed mechanical arm configuration in sequence to adapt to corresponding control under different environments.

The invention discloses an inverse E-type radio frequency power amplifier suitable for 5G. The inverse E-type radio frequency power amplifier comprises an input circuit, an input matching and stabilizing network, a filter bias circuit, a transistor, a harmonic control network with parasitic compensation, a fundamental wave matching circuit and an output circuit, wherein the harmonic control network comprises a first microstrip line, a second microstrip line, a third microstrip line and a fourth microstrip line; the input matching and stabilizing network is used for matching source impedance to50 ohms and ensuring that the transistor can stably work in a working frequency band; and the filter bias circuit is used for accessing drain bias voltage and grid bias voltage. The inverse E-type radio frequency power amplifier has the advantages that parasitic parameters of the drain electrode pin of the transistor can be compensated; and on the premise of ensuring good switching characteristics of the inverse E-type radio frequency power amplifier, the influence of higher harmonics is reduced, and the drain voltage and the drain current of the transistor cannot be overlapped and distortedin low-frequency and high-frequency working environments, and the working efficiency is high, and the output performance is good, and the drain peak voltage and the drain peak current of the transistor are low, and the transistor is not easy to break down.

The invention discloses a test circuit of a dynamic reactive power compensation and harmonic control device and a test method thereof. A static var generator (SVG) is used as a device for testing a test object, wherein a power main inlet wire is connected with a miniature test bus; the SVG is connected with the miniature test bus after being connected the test object in parallel; a SVG branch current transformer and a test object branch current transformer are sequentially connected in series with circuits of the SVG and the test object; a SVG branch grid-connected circuit breaker and a test object grid-connected circuit breaker are also connected in series with the SVG and the test object; and the tripping outlets of the SVG branch grid-connected circuit breaker and test object grid-connected circuit breaker are in parallel connection. The test circuit not only can be used for effectively testing the dynamic adjustment function, filter function and output capacity continuous change function of the tested reactive power compensation device, but also can be used for achieving full-capacity test, temperature rise test and negative sequence compensation capability test of a large-capacity dynamic reactive power compensation device in a system with small power capacity.

The invention relates to the field of stable operation of three-phase PWM converters, in particular to a three-phase PWM converter in a voltage unbalance condition and an optimal control method of the three-phase PWM converter, and aims at effectively solving the problem of secondary fluctuations of a negative sequence component of AC side current and active power of the three-phase PWM converter in the voltage unbalance condition. The three-phase PWM converter comprises a three-phase full-bridge rectifier circuit and a power compensation circuit. The converter is based on harmonic detection and proportional-integral and harmonic control principles and is applied to a mathematical model of the three-phase PWM converter in an alpha-beta coordinate system free of phase detection for control; the controller comprises an AC controller and a DC controller; and elimination of the secondary fluctuations of negative sequence current and the active power is achieved through control on positive and negative sequence current of an AC side, the AC side current and DC voltage.

The invention provides a broadband Doherty power amplifier with continuous inverse class F and class J mixed. The broadband Doherty power amplifier comprises a broadband Wilkinson power divider, a phase compensation line, a carrier power amplification circuit, a peak power amplification circuit and a broadband post-matching circuit. The carrier power amplification circuit comprises a carrier broadband input matching circuit, a carrier amplifier transistor and an impedance converter; the peak power amplification circuit comprises a peak broadband input matching circuit, a peak amplifier transistor, a peak harmonic control/suppression network, a peak fundamental wave tuning network and a reverse phase compensation line; and the broadband post-matching circuit comprises a carrier harmonic control network and a post-matching tuning network. The carrier amplifier works in a continuous inverse class F mode when input power is saturated, works in a class J mode when input power is back-off by 6dB, and the peak amplifier works in a continuous inverse class F mode when input power is saturated and does not work when input power is back-off by 6dB.

The invention discloses an improved broadband self-adaption resonance control method for an active power filter. The method comprises the steps that the three-phase voltage of a common coupling point is collected, and a phase-locked loop is used to acquire the voltage frequency fpll and the phase theta; a harmonic detection module extracts the harmonic signal command of nonlinear load current iL; the harmonic signal command is added to an output active current command acquired through a direct current voltage controller; subtracting the command and an output current feedback signal to acquire the input error signal of a current controller; the current controller composed of a harmonic controller and a PI controller is used to acquire the output control amount; and the output control amount, the common coupling point voltage feed forward amount and the filter capacitor current feedback amount through an active damping module are added to acquire a PWM wave modulation instruction signal.

Circuits and methods related to power amplifier efficiency based on multi-harmonic approximation. In some embodiments, an output network circuit can be provided for multi-harmonic control of a radio-frequency (RF) power amplifier. The output network circuit can include an impedance matching network configured for a fundamental frequency of the power amplifier. The output network circuit can further include a broadband harmonic trap in communication with the impedance matching network. The broadband harmonic trap can be configured to substantially trap a plurality of harmonics associated with the fundamental frequency. The output network circuit can further include a dipole network in communication with the broadband harmonic trap. The dipole network can be configured to tune reactances resulting from the operation of the broadband harmonic trap.