52results about How to "Phase coincidence" patented technology

The invention discloses multichannel radar amplitude and phase automatic correcting method and device. The method comprises the following steps of: before a radar system works, respectively feeding the same radio frequency test signal into various receiving channels of a multichannel radar system by a feed source to obtain the phase characteristic and the amplitude characteristic of various receiving channels; calculating a phase difference and an amplitude specific value between other channel signals and a reference signal by using one of channel signals as a reference signal; and then enabling the radar system to work, carrying out automatic correction on target echoes of all the channels by utilizing the obtained phase difference and the amplitude specific value so as to ensure the consistency of all the channels on amplitudes and phases. When a transmission frequency point is changed or a radar working environment is changed, the amplitude and phase characteristics of the receiving channels are unavoidably changed; and the invention can accurately and conveniently measure and correct the change of the amplitude and phase characteristic and ensure the consistency of all the channels, thereby expanding the working frequency range and the environmental adaptability of radar and improving the maintainability of the radar.

The invention discloses a method for compensating delay and frequency response characteristics of multi-output channel sound system and system implementation thereof. The method comprises the following steps that firstly, phase difference between channels of a multi-channel output device is measured, so that the situation that the multi-channel output device itself is in the state of synchronously outputting signals is ensured; then the delay of the signals which are output by the multi-channel output device and pass through a signal processing system, a loudspeaker box and a space transmission routine to reach a specific audition area is estimated through a delay estimation method, and delay compensation is conducted on the channels by comparing delay difference between the channels; finally, an FIR frequency response compensating filter is designed and achieved according to actually detected frequency response curves of a signal transmission routine, and the part above the low and medium frequency in the frequency response curves of the multiple channels is compensated into a straight line through the filter as far as possible. By means of the method, when sound waves transmitted out of each loudspeaker box reach the audition area, the phases of the sound waves are basically the same, and the frequency response characteristics of the channels are basically the same.

The invention provides a flexible island grid-connection control device and method for smart power grids. The device comprises flexible inversion units, single-phase electric power detection units, GPS phase detection units, an island grid-connection detection unit, a communication unit and a master control unit. Each flexible inversion unit comprises an angle form differential voltage topological circuit and a star connection type inverter circuit. Each single-phase electric power detection unit is connected with the output end of the corresponding star connection type inverter circuit and a PCC nodal point. Each GPS phase detection unit is connected to the output end of the corresponding star connection type inverter circuit and a PCC nodal point. The input end of the island grid-connection detection unit is connected to the output ends of the single-phase electric power detection units at the PCC nodal points and the output ends of the GPS phase detection units at the PCC nodal points. The output end of the island grid-connection detection unit is connected with the input end of the master control unit. According to the flexible island grid-connection control device, the flexible inversion units composed of novel topological structures can make a micro power grid and a main power grid conduct flexible grid-connection and conduct switching of islanding modes, so that impact of the micro power grid on the circuits is reduced.

A liquid crystal panel ( 2 ) includes scanning signal lines ( 31 ) for supplying scanning signals to gate electrodes ( 20 ) of TFTs ( 14 ), and data signal lines ( 32 ) for supplying data signals to data electrodes ( 24 ) of TFTs. The liquid crystal panel further includes auxiliary capacitive electrode pads ( 27 a) for use in forming auxiliary capacitance and an auxiliary capacitive lines ( 33 ) so as not to generate a capacitive bond with the scanning signal lines. The liquid crystal panel is driven at a rewriting frequency of a screen of not more than 30 Hz. As a result, the liquid crystal panel can be driven at a low consumption power while maintaining a desirable display quality of the liquid crystal panel.

A photovoltaic micro-network-system off-grid / grid-connected control method based on inverse droop control relates to the off-grid / grid-connected switching field. By using traditional droop control, an output current of an inverter can not be directly controlled; under a grid connected state, quality of electric energy injecting into a power grid is uncontrollable; and a grid connected current wave shape can not reach an ideal state. By using the method of the invention, the above problems are solved. Under the off-grid and grid-connected states, an uniform current type controller is adopted. An off-grid constant power output module is used for driving a switch tube T0 so that output power of a preceding-stage converter is equal to input power of a backward-stage inverter. An off-grid inversion voltage output module is used for driving a full-bridge inversion circuit so as to stabilize a direct current bus voltage and output a sine alternating current voltage. A grid-connected power maximization output module is used for driving the switch tube T0 so as to realize maximum power output of the inverter. A grid-connected current output module is used for driving the full-bridge inversion circuit so as to stabilize the direct current bus voltage and make an output current unit power factor be in a grid-connected state. The method is used for off-grid and grid-connected seamless switching of the inverter.

The invention discloses a method for measuring phase of a power transmission and distribution line, which comprises the following steps of suspending a set of three-phase short circuit grounding wire on both of two side lines on a outlet line knife switch or a cable head of a transformer station to be measured; supposing two sides of the line as an A transformer station and a B transformer station; supposing each phase on the A side and the B side of the line as A phase, B phase and C phase; supposing the B transformer station as a known system phase, the phase of the A transformer station as a to-be-measured phase; performing the testing work in the A transformer station; detaching the three-phase short circuit grounding wire of the A transformer station on the line; orderly detaching grounding conducting wires of the B transformer station on the line; remotely measuring resistance, namely measuring the phase under the condition that the two ends of the line are not electrified; ensuring that the phase of the line is matched with that of the system; and remotely measuring the insulating resistance value between the conducting wire and the ground.

The invention provides a phase-locked loop circuit, a system with multiple phase-locked loops and an output phase synchronization method thereof. The invention includes a frequency divider for frequency division of an output signal, a sampler which samples the frequency-divided signal based on the output signal to obtain a feedback signal to ensure that the phase of the feedback signal is consistent with the phase of the output signal, a phase frequency detector which determines the phase difference between the feedback signal output by the sampler and the input crystal oscillator signal to generate a pulse signal, a charge pump which generates tuning voltages based on the pulse signal, and a voltage controlled oscillator which adjusts the frequency of the output signal based on the tuningvoltages. In the invention, a sampling method is adopted to realize the phase consistency of the feedback signal and the output signal of the phase-locked loop circuits. Thus the phase consistency between the output signal and the input crystal oscillator signal is greatly improved. Besides, in the system with multiple phase-locked loops, the phase of the output signals of all phase-locked loop circuits is ensured to be consistent so as to improve the system performance.

The invention provides a distributed power supply grid connection control method, in which voltage recovery control, frequency recovery control and phase recovery control are added into droop control, thereby realizing the stable transition of a distributed power supply from island operation to grid connection operation, and ensuring the stable and efficient grid connection of the distributed power supply. The grid connection control method can keep the voltage amplitudes, frequencies and phases on two sides of a distributed power supply grid connection switch PCC essentially consistent, furthermore realize the stable transition of the distributed power supply from island operation to grid connection operation, and guarantee the stable and efficient grid connection of the distributed power supply.

Provided are a power amplification device which is provided with a function of preventing deviation of the amplitude and phase of an output signal having amplified envelope variation from expected values, and a transmission device and a communication device both using the power amplification device. The power amplification device comprises a variable phase shifter circuit (10) which phase-shifts an input signal; first and second adder circuits (11a), (11b) which generate first and second constant envelope signals; first and second amplifier circuits (12a), (12b); first and second amplitude detection circuits (13a), (13b) which detect amplitudes; a first amplitude control circuit (20) which varies the amplitudes of first and second constant envelope vector generation signals; an output adder circuit (14) which performs vector addition of first and second amplified signals to generate the output signal; a phase shift control circuit (30) which controls the phase shift amount of the variable phase shifter circuit; a gain control circuit (40) which controls the gains of the first and second adder circuits; and a second amplitude control circuit (50) which varies the amplitudes of the first and second constant envelope vector generation signals.

The invention provides a distributed receiving array channel error calibration method based on a microwave photon stable-phase transmission link. The method comprises the following steps that firstly, a correction signal is modulated to an optical domain through a directly modulated laser, then the signal is divided into n optical carrier microwave signals through optical fibers with equal length, a photoelectric detector at each unit position of a receiving end converts the optical microwave signals into equal-phase electric signals and transmits the electric signals to a receiving antenna array so that relative stability of signal phases at all receiving end positions can be ensured; and finally (n+1) paths of equiphase calibration signals enter a receiver from all receiving channels and reference channels, and data analysis and time delay and amplitude phase estimation are carried out at a signal processing terminal. A microwave photon stable-phase transmission link is used for transmitting a calibration signal in a long distance, and it is guaranteed that the amplitude and the phase of the calibration signal fed into a front end of a distributed receiving array channel are kept consistent; and the received calibration signal is processed, and the relative amplitude, phase and time delay error among the channels are estimated.

The invention discloses a leading type control method and system applied to a driving magnetic suspension system. The leading type control method comprises the following steps that a displacement signal is measured; differential operation is carried out on displacement to obtain a speed signal; and a PID control, an adaptive control and a sliding mode variable structure control are introduced, thelocated stage of a guide rail is judged according to a value of the speed signal, and the strength of three control algorithms is changed to form different characteristic leading control strategies by adjusting factor coefficients of the three control algorithms in an online mode. In an initial operation stage, a stable operation stage and a disturbance affected operation stage, effective controlis carried out according to the characteristic showed by the system; a "soft switching" mode is adopted to avoid the instability caused by the switch in the transition period; and the period and thephase position of the input signal are ensured to be identical completely, so that a control signal undergoes no jump switching under the absolute synchronization.

The present invention provides a calendar mechanism which can easily and reliably cause first and second date indicators to coincide in rotation phase, and an analog timepiece equipped therewith. The calendar mechanism of the analog timepiece includes a first date indicator (40) including a first date character indication portion which indicates the ones column of the date, a first date indicator gear portion, and a drive cam portion which defines an endless ring-shaped cam face; a drive cam lever (60) which includes a driven lever portion (63) whose one end portion abuts against the drive cam portion, and an operating lever portion (62) which includes a first fan-shaped gear portion at the leading end portion, the operating lever portion being pivoted in accordance with the driven lever portion; and a second date indicator (50) which, being rotatable, includes a second date character indication portion (53) which indicates the tens column of the date, and a second fan-shaped gear portion (52) meshing with the first fan-shaped gear portion. The first fan-shaped gear portion and second fan-shaped gear portion have specified teeth (68, 58) which are brought into selective meshing engagement in a condition in which the first date indicator and second date indicator coincide in rotation phase.

The invention discloses a control method for an auxiliary power supply system. The method is applied to each parallel inverter and comprises controlling the inverter in a power drop mode after startup; judging whether a received mode control command is a current sharing command or a non-current sharing command; if the command is the current sharing command, controlling the output voltage of the inverter in a synchronous modulation manner so that carriers of all the inverters in the auxiliary power supply system are maintained at the same phase; if the command is the non-current sharing command, calculating the phase shift time coefficient, utilizing the phase shift time coefficient to adjust the phase of the output voltage when the output voltage of the current inverter is controlled according to the synchronous modulation mode to reduce the phase difference of the carriers of the inverters in the auxiliary power supply system. By means of the scheme, the switching loop current of theauxiliary power system is effectively reduced. A control system and device for the auxiliary power supply system is further disclosed, and corresponding technical effects are achieved.

When a distortion of an output waveform of an alternating-current generator is improved, an output voltage control apparatus of a generator, which has versatility, is obtained. The generator (1) includes a generator winding (2) and an excitation winding (3) wound around a stator side, a field winding (5) wound around a rotor (4), and a rectifier (12) for rectifying a current generated by the excitation winding (3) and supplying the rectified current to the field winding (5), the output voltage control apparatus includes a field current drive means (20) for comparing an output voltage generated to the generator winding (2) with a reference wave whose distortion ratio is 0% and flowing a field current to the field winding (5) by adjusting a drive timing of a PWM signal output by a drive unit (24) based on a result of the comparison.

The invention relates to a phase calibration structure of a magnetic resonance radio frequency power amplifier. The magnetic resonance radio frequency power amplifier comprises power amplification modules of N power amplifier tubes and a power synthesis module, wherein the power synthesis module is used for power amplification and synthesis of N input signals. The phase calibration structure is characterized by comprising N phase shifters, N phase discriminators and N directional couplers; each input signal of N input signals is connected with one phase shifter and then connected with an input end of one power amplifier tube in one power amplification module, an output end of the power amplification tube is connected with an input end of one directional coupler, and an output end of the directional coupler is connected with one phase discriminator and then connected with a phase shifter input end corresponding to the signal; besides, output ends of all the power amplifier tubes are connected with the power synthesis module. The phase calibration structure has the advantages as follows: the phase difference generated by the power amplifier tubes is automatically compensated, phases of the output signals are consistent, and the optimum synthesis efficiency is realized.

The invention discloses an antenna array element of a vertically integrated filter. The antenna array element includes a dual polarized cavity filter and a dual polarized radiating element integratedon top of the dual polarized cavity filter; the dual polarized cavity filter is composed of a plurality of dual polarized resonance cavities which are connected in order from bottom to top, and a coupling window is arranged between the adjacent dual polarized resonance cavities. The invention also discloses a millimeter wave antenna array and a millimeter wave communication device. The element integrates the radiating element and the filter in a vertical direction, has the advantages of compact structure and small space occupation, and more importantly, ensures that the phases and amplitudes of signals transmitted by each array element in the antenna array are substantially the same.

Alternately arrange 2m stator rings in the axial direction, where m is a natural number greater than or equal to 2 (m=2 in the embodiment), each stator ring is formed with a plurality of teeth (31b-34b) and connects the teeth to each other 2m-1 slots (41, 42, 43) are formed between 2m stator rings, and the windings (36, 37, 38) in each slot (41, 42, 43) will be accommodated in the return path The windings (36, 37, 38) in the slots (41, 42, 43) at a distance of m are connected in series so that the excitation directions are opposite, so that the phases of the magnetic flux passing through the teeth (31b-34b) of each stator ring are respectively staggered by 360 ° / 2m, it is possible to abolish the winding portion (transition portion) that does not contribute to the torque, and since the magnetic circuit of each phase is shared through the return path (31a to 34a), a thin and high-output salient pole motor can be obtained, and Since the magnetic circuit of the wave winding motor is formed, the output torque can be increased compared with the salient pole concentrated winding motor.

The invention discloses an interference-resistant antenna unit capable of improving amplitude phase consistency. The interference-resistant antenna unit comprises a metal isolation surrounding frame,a microstrip antenna, a power division phase-shift feeding plate, an antenna lining plate and a coaxial connector, wherein the metal isolation surrounding frame is a metal frame of which the top is opened and the circumference is closed, the microstrip antenna is arranged in the metal frame, a gap is reserved between the circumference of the microstrip antenna and an inner wall of the metal frame,the top of the microstrip antenna is lower than the top of the metal frame, the power division phase-shift feeding plate is arranged at an inner side of the bottom of the metal frame, the antenna lining plate is arranged at an outer side of the bottom of the metal frame, and the coaxial connector is used for feeding the microstrip antenna by the power division phase-shift feeding plate. By the interference-resistant antenna unit, the performance index of the amplitude phase consistency of each antenna unit is effectively improved, the interference-resistant performance is obviously improved,and the requirement of system stable positioning of an interference-resistant array antenna under a three-interference system is met. The invention also provides the interference-resistant array antenna.

A mobile communication base station based on a metamaterial antenna comprises a content access module, a radio remote module, a software radio configuration module and the metamaterial antenna. The content access module receives contents of communication signals of various systems provided by various information sources; the radio remote module is used for converting the communication signals of the various systems between analog radio-frequency signals and baseband signals and processing redundancy in the radio-frequency signals; the software radio configuration module carries out corresponding configuration on the communication signals of the various systems processed by the radio remote module for the metamaterial antenna; the metamaterial antenna converts electrical signals into electromagnetic waves or allows the electromagnetic wave to be converted into the electrical signals. Therefore, consistency of analog discrete components of the mobile communication base station is kept, and consistency of the amplitude and the phase of the signals is guaranteed; the size of a product becomes small, the weight of the product is reduced, and thus miniaturization, a light-weight trend and integration of the whole mobile communication base station are achieved.

The invention discloses a treatment device based on laser with wavelength of 940 nm. The treatment device is characterized by comprising a laser device, a cooling system and a probe handle, wherein the laser device is used for emitting the laser with the wavelength of 940 nm and is connected with the probe handle through a transmission optical fiber; the cooling system is used for providing a cooling working medium and is connected with the probe handle through a cooling working medium conveying pipeline; the laser with the wavelength of 940 nm emitted by the laser device has relatively good tissue penetrability; absorption of hemoglobin to the laser is increased, absorption of melanin and the like to the laser is reduced, treatment of vascular skin diseases such as fat and thick type port-wine stains with relatively large lesion blood vessels and face angiotelectasis with relatively small lesion blood vessels is realized, and the treatment device is relatively good in treatment effectand relatively good in universality; and meanwhile, a mode of coupling refrigerant surface spray cooling with cold air cooling is adopted, so that thermal injury to epidermis and dermis is effectively avoided.

The invention discloses an AC constant current source system, comprising: an AC / DC rectification module, a DC / AC inverter module, an energy conversion module, a current detection module, a voltage detection module, and a digital control module. The digital control module is based on the AC / DC The port voltage of the rectifier module, the port voltage and output current of the transducer module control the DC / AC inverter module, and the high-voltage and low-current power output by the DC / AC inverter module is converted into a low-voltage and high-current power supply by the transducer module. The module outputs AC constant current. The invention adjusts the output current of the transducer module through the error control method, keeps the output AC current consistent with the target current amplitude, frequency and phase, and the system has a short operating cycle, precise control, strong real-time performance, good reliability and high efficiency, and the AC constant The current source is multi-level adjustable, suitable for various occasions such as low-voltage electrical appliance testing and other AC constant current source power supply.

The invention provides an electrified railway cophase power supply scheme based on uncontrolled rectification and step wave synthesis inversion, and belongs to electrified railway cophase power supply schemes. [System]: An input end of a phase-shifting transformer is electrically connected with a three-phase high-voltage alternating current, an output end of the phase-shifting transformer is connected with a three-phase uncontrolled rectifier, and the three-phase uncontrolled rectifier is connected with a single-phase inverter through a filtering capacitor; a DC accumulator is connected between the filtering capacitor and the single-phase inverter, and the DC accumulator provides interfaces for accessing other energies; and output ends of the single-phase inverter are respectively connected with an uplink overhead line system and a downlink overhead line system. [Method]: An inversion side performs step wave synthesis modulation, and phase information of all traction substation is provided by a GPS synchronous clock; the uplink and downlink overhead line systems are in a parallel operation state; and a proper number of energy storage batteries are disposed in a DC filtering link, residual regenerated energy when a small probability event that brake power is greater than traction power occurs is cached, and interfaces for introducing the other energies are provided. [Advantages]: the scheme has the advantage of mutual standby, and capacity investment is saved.

The embodiment of the invention discloses an ultra-wideband odd-path power divider. The ultra-wideband odd-path power divider comprises a microstrip line, wherein the microstrip line comprises an impedance conversion line and a first microstrip lead to a (2n+1)th microstrip lead, the input end of the impedance conversion line is used as an input port of the microstrip line, the output end of the impedance conversion line is connected with the input end of each microstrip lead, and the output end of one microstrip lead is used as an output port of the microstrip line; the ith microstrip lead and the jth microstrip lead have the same and symmetrical line structure, and the chamfer angle of the ith microstrip lead is equal to the chamfer angle of the jth microstrip lead; the length of the pthmicrostrip lead is less than that of the qth microstrip lead. In the embodiment of the invention, the symmetrically arranged microstrip leads are provided with the equal chamfer angles, so that the electromagnetic wave amplitude of each microstrip lead can be compensated at the output end of the impedance conversion line; and by lengthening the multiple paths of microstrip leads, phase compensation can be performed on the multiple paths of microstrip leads, so that the phases of the microstrip leads tend to be consistent.

A bidirectional homologous coherent microwave optical fiber phase-stabilized transmission method, the bidirectional homologous coherent microwave optical fiber phase-stabilized transmission system using the method includes a front-end device and a back-end device; the front-end device and the back-end device are connected by a dual-core optical fiber , to transmit uplink and downlink optical signals respectively; a phase-stable reference reference source is set in the front-end equipment, and the phase-stable reference reference source generates a phase-stable reference reference electrical signal, and the phase-stable reference reference electrical signal is modulated into a phase-stable reference reference optical signal, which is passed through the front-end The dual-core optical fiber between the equipment and the back-end equipment is transmitted to the back-end equipment, and then returns through the original path of the dual-core optical fiber to become the uplink and downlink phase-shifted information optical signals; the uplink and downlink phase-shifted information optical signals are demodulated into uplink and downlink The phase difference generated by the phase comparison between the phase-shifting information electrical signal and the phase-stable reference electrical signal is converted into an uplink and downlink phase-shifting control signal, and the phase-stabilization control is performed on the uplink and downlink optical signals transmitted in the dual-core optical fiber, thereby realizing bidirectional synchronization. Phase-stable transmission of source coherent microwave fibers.

In order to solve the problem of low reliability of parallel operation of generator sets in the prior art, the present invention provides a phase synchronization method for parallel operation of multiple generator sets. The generator set includes an engine generator, a rectifier unit, an inverter unit and an output filter. It also includes a main control unit and a throttle control unit; it also includes a current sampling unit, a voltage sampling unit and a voltage zero-crossing unit, and the output ends of the output filtering unit are respectively connected with the current sampling unit, the voltage sampling unit and the voltage zero-crossing unit. In this application, the actual output current of the generator set, the value of the output voltage, and the time difference between the actual zero-crossing point of the output voltage and the software zero-crossing point are collected, and compared with the preset value in the main control unit of the generator set, the period of the output voltage is adjusted. The value and voltage amplitude, the phase of synchronous output voltage, the power distribution of different units in parallel, improve the reliability of parallel operation of generator sets, and improve the efficiency and economy of unit operation.

The invention discloses an intermediate-frequency sine-wave alternating-current power supply parallel operation system and a control system thereof. The parallel operation system comprises an intermediate-frequency sine-wave power supply host and a plurality of intermediate-frequency sine-wave power supply slaves, wherein the intermediate frequency sine wave power supply host and all the intermediate frequency sine wave power supply slaves are respectively provided with a parallel operation input interface and a parallel operation output interface. The parallel operation output interface of the intermediate frequency sine wave power supply host is connected with the parallel operation input interface of the first intermediate frequency sine wave power supply slave; the parallel operation output interface of the first intermediate-frequency sine-wave power supply slave is connected with the parallel operation input interface of the second intermediate-frequency sine-wave power supply slave, and so on, the parallel operation output interface of the (N-1) th intermediate-frequency sine-wave power supply slave is connected with the parallel operation input interface of the Nth intermediate-frequency sine-wave power supply slave, wherein the N is the total number of the intermediate-frequency sine-wave power supply slaves and is greater than 1. According to the parallel operation system, an interface corresponding to each slave does not need to be added for a host structure, so that the problem of capacity expansion limitation in the prior art is solved.

The invention discloses a control method for an auxiliary power supply system. The method is applied to each parallel inverter and comprises controlling the inverter in a power drop mode after startup; judging whether a received mode control command is a current sharing command or a non-current sharing command; if the command is the current sharing command, controlling the output voltage of the inverter in a synchronous modulation manner so that carriers of all the inverters in the auxiliary power supply system are maintained at the same phase; if the command is the non-current sharing command, calculating the phase shift time coefficient, utilizing the phase shift time coefficient to adjust the phase of the output voltage when the output voltage of the current inverter is controlled according to the synchronous modulation mode to reduce the phase difference of the carriers of the inverters in the auxiliary power supply system. By means of the scheme, the switching loop current of theauxiliary power system is effectively reduced. A control system and device for the auxiliary power supply system is further disclosed, and corresponding technical effects are achieved.

The invention relates to series connection and parallel connection methods of a series motor stator winding. By using the methods, internal series connection and parallel connection of upper and lower submersible motor stator windings can be cleverly realized; the number of turns of each corresponding stator, a size of each phase current and phases are completely consistent and generated stator magnetic potential waves are the same so that mechanical properties of two motors are consistent and load distribution is balance. The series-connected lower motor has no individual outgoing cable so that a radial space size of the upper motor is not occupied and a radial size of the motor can be reduced maximumly.

A photovoltaic micro-network-system off-grid / grid-connected control method based on inverse droop control relates to the off-grid / grid-connected switching field. By using traditional droop control, an output current of an inverter can not be directly controlled; under a grid connected state, quality of electric energy injecting into a power grid is uncontrollable; and a grid connected current wave shape can not reach an ideal state. By using the method of the invention, the above problems are solved. Under the off-grid and grid-connected states, an uniform current type controller is adopted. An off-grid constant power output module is used for driving a switch tube T0 so that output power of a preceding-stage converter is equal to input power of a backward-stage inverter. An off-grid inversion voltage output module is used for driving a full-bridge inversion circuit so as to stabilize a direct current bus voltage and output a sine alternating current voltage. A grid-connected power maximization output module is used for driving the switch tube T0 so as to realize maximum power output of the inverter. A grid-connected current output module is used for driving the full-bridge inversion circuit so as to stabilize the direct current bus voltage and make an output current unit power factor be in a grid-connected state. The method is used for off-grid and grid-connected seamless switching of the inverter.