266 results about "Virtual synchrony" patented technology

The invention relates to a virtual synchronous generator control method based on self-adapting moment inertia. The output of a grid-connected inverter in distributed generation is connected with an AC bus of a filter capacitor Cf which is in parallel connection with the grid-connected inverter through a filter inductor Lf; sampling is performed to obtain the output power, the voltage and the current of an output interface of an inverter; the output power, the voltage and the current are transmitted to a VSG (virtual synchronous generator) algorithm; the calculated terminal voltage of a VSG stator is sent to be controlled by a voltage external loop; the voltage external loop adopts a PI controller to stably load the voltage; the current of the filter capacitor is sent to be controlled by a voltage internal loop; the voltage internal loop adopts a PI controller to increase the response speed; a control signal is outputted by a voltage-current dual-closed loop to the grid-connected inverter; the moment inertia in the virtual synchronous generator in the control method can be changed in a self-adapted manner according to the change capacity of the system frequency. Through the adoption of the virtual synchronous generator control method disclosed by the invention, the transient state process of the system is reduced; a great deal of harmonic waves in the system is offset; the stability of frequency and the stability of voltage can be improved; the adaptability and the power supply quality of a micro-electrical network are improved; the problem that in a conventional method, the output frequency is reduced, is solved.

This invention discloses a system and method to operate a doubly-fed induction generator (DFIG) as a grid-friendly virtual synchronous generator (VSG). It comprises a DFIG modeled as a virtual differential gear that links a rotor shaft driven by a prime mover, a virtual stator shaft coupled with a virtual synchronous generator G and a virtual slip shaft coupled with a virtual synchronous motor M, and a variable frequency drive that behaves as a virtual synchronous motor-generator set to regulate the speed of the virtual synchronous motor M so that the speed of the virtual stator shaft, i.e., the speed of the virtual synchronous generator G, is within a narrow band around the grid frequency even when the rotor shah: speed changes. As a result, a grid-connected DFIG can be controlled to behave like a virtual synchronous generator without using a PLL.

The invention discloses a multiprocessor System and synchronous engine device thereof. the synchronous engine includes: a plurality of storage queues, wherein one of the queues stores all synchronization primitives from one of the processors; a plurality of scheduling modules, selecting the synchronization primitives for execution from the plurality of storage queues and then according to the type of the synchronization primitive transmitting the selected synchronization primitives to corresponding processing modules for processing, scheduling modules corresponding in a one-to-one relationship with the storage queues; a plurality of processing modules, receiving the transmitted synchronization primitives to execute different functions; a virtual synchronous memory structure module, using small memory space and mapping main memory spaces of all processors into a synchronization memory structure to realize the function of all synchronization primitives through a control logic; a main memory port, communicating with virtual synchronous memory structure module to read and write the main memory of all processors, and initiate an interrupt request to processors; a configuration register, storing various configuration information required by processing modules.

The invention discloses an overrunning virtual synchronous generator (VSG+) method with rotary inertia and damping self-optimization-trending. The method comprises the following steps: step one, a mechanical equation and an electromagnetic equation of a virtual synchronous generator (VSG) are established; step two, the rotary inertia J and damping D in a VSG model are increased as |delta f| is increased, wherein delta f is an absolute value of a difference between a power network rated frequency and the actual frequency of the VSG; and step three, according to self-adjustment of the rotary inertia J and the damping D, closed-loop control is performed on the |delta f|, and finally, grid connection of a distributed photovoltaic power generation system is realized. According to the VSG+ method with the rotary inertia and damping self-optimization-trending, provided by the invention, the rotary inertia J and the damping D in the VSG are adaptively adjusted as the |delta f| changes, the rotary inertia J and the damping D after adjustment then perform feedback regulation on the |delta f|, and finally, zero impact during grid connection of photovoltaic inverters is realized, such that the acceptance capability of a power network for the distributed photovoltaic power generation system is improved.

The invention discloses a grid connection method of an MMC-type light direct-current power transmission system. A virtual synchronization control method is combined with an MMC so that switching of operation modes of the MMC-type light direct-current power transmission system can be carried out, a special synchronization control circuit is needless, the system can be automatically synchronized with a power grid before grid connection, pre-synchronization time is short, the system can accurately follow frequency of the power grid after grid connection, and friendly grid connection is achieved.

The invention discloses a voltage control type virtual synchronizing method of a double-feed wind power generator set. Through simulating inertia and a frequency-modulating and voltage-modulating characteristic of a synchronizer, the set can be different from a characteristic of no electric grid frequency change response in a traditional current control type, thereby possessing capability of supporting voltage and frequency of a weak power grid based on the voltage control type through virtual inertia. The method provides and realizes a VCT-DFIC virtual synchronous control structure of which an inner ring is controlled by an improved double-feed generator stator voltage rotor current double-closed-loop structure based on adaptive stator virtual impedance and transmission line sag voltage feedforward compensation in a control manner which includes crossed control between stator voltage and rotor current and furthermore an outer ring is controlled by a virtual synchronous realizing algorithm. The method realizes output power control in VCT-DFIG grid integration operation in a weak grid condition with any actual impedance and effective decoupling, and furthermore a designed control structure realizes higher inertia and frequency supporting capability of the double-feed generator.

The invention discloses a method, a device and a system for controlling photovoltaic grid connection on the basis of a virtual synchronous machine. A photovoltaic grid connection system on the basis of the virtual synchronous machine comprises a photovoltaic cell panel, a DC/DC converter and a DC/AC inverter. The photovoltaic cell panel is connected with direct-current bus, one end of the DC/DC converter is connected with the direct-current bus, the other end of the DC/DC converter is connected with an energy storage cell, the direct-current bus is connected with a direct-current side of the DC/AC inverter, and an alternating-current side of the DC/AC inverter is connected into a transformer. The method, the device and the system have the advantage that the problem that an existing photovoltaic grid connection system is incapable of simultaneously controlling photovoltaic array terminal voltages and implementing functions of an existing virtual synchronous machine can be solved by the aid of the method.

The invention discloses a control method for a virtual synchronous generator capable of being adapted to imbalanced power grid and load conditions. The control method comprises the following steps that 1) an active ring simulates the mechanical characteristics of a speed controller and a rotor to obtain an output positive sequence voltage frequency and a phase position instruction; 2) a reactive ring simulates a n excitation controller to obtain an output positive sequence voltage amplitude value instruction; 3) a voltage-control and virtual synchronous impedance ring simulates the electrical characteristics of a stator; 4) positive and negative sequence current rings carry out accurate tracking on the positive and negative sequence current instructions respectively, and eliminates the negative sequence current output; and 5) a modulation signal is obtained by the combination of the positive and negative sequence current rings, and then the modulation signal is subjected to PWM to obtain a switching signal. Compared with the prior art, the output active power fluctuation and frequency fluctuation caused by imbalance of the power grid can be eliminated; and in addition, it is ensured that the output current of the virtual synchronous generator is balanced constantly, so that overhigh electrical stress of a certain bridge arm of the inverter can be avoided.

The invention discloses a virtual impedance voltage converter-based control method of a virtual synchronous motor. Output voltage and current of a voltage converter is controlled to have the characteristic of a synchronous motor through electric and mechanical main parts of the virtual synchronous motor, wherein the electric part comprises a novel virtual impedance simulation algorithm, a conventional converter current inner ring and a modulation strategy and the mechanical part comprises a power calculating module, a rotor mechanical equation and a virtual damping module. The virtual impedance voltage converter-based control method of the virtual synchronous motor can be used for simulating winding impedance without introducing a differential term of current output by the converter, so that the influence on impedance simulation by an extra low pass filter is overcome, and the current inner ring control of a parallel converter is not sacrificed, and therefore, alternating current is controlled, and the converter has the capacity of preventing current fluctuation, overcurrent and even impact without quick current inner ring control. A silent pole motor and a non-salient pole motor can be simultaneously simulated.

The invention discloses a fault protection and ride-through control system and method for a virtual synchronous machine. The fault protection and ride-through control method for the virtual synchronous machine comprises the following steps of measuring the three-phase voltage and current on the inverter output side, and calculating the active power according to an instantaneous power theory; if an asymmetric voltage drop fault occurs, extracting the voltage positive sequence component of the power grid to obtain a switching signal, and calculating the correction amount when the active power and the reactive power need to be output; if the voltage drop depth of the power grid exceeds a preset value, obtaining a supporting voltage through a power system stabilizer; and performing calculation and regulation through an active equation, a reactive equation, a torque inertia equation, and an electromagnetic torque equation to obtain the amplitude value and the phase angle setting value of the output voltage, and performing PWM modulation. According to the fault protection and ride-through control system and method, an energy storage unit is adopted for performing voltage-stabilizing control; and the direct bus voltage is stabilized while it is ensured that overcurrent does not occur, so that huge voltage fluctuation is avoided, and the performance degradation of the system is prevented.

The invention provides an augmented reality-based virtual synchronization display method and system. The method comprises the steps of: S1, acquiring first feature point information in a preset reality scene image and inputting the first feature point information into a simultaneous localization and mapping module to create a three-dimensional virtual scene; S2, performing movement tracking on a user and obtaining first movement state information in the reality scene of the user; S3, setting second movement state information in the reality scene of all virtual models, except for a first client virtual model corresponding to a first client, in the three-dimensional virtual scene; S4, displaying all the virtual models, except for the first client virtual model, in the three-dimensional virtual scene in the reality scene; S5, synchronizing the first movement state information and the second movement state information to a plurality of clients. The SLAM technology-based movement tracking and three-dimensional virtual scene modeling reinforce the interaction between players and virtual objects in the real world and improve the user experience effect.

The invention provides a control method and a device for connecting wind power to a flexible HVDC transmission system. Firstly, the actual frequency of an AC grid at a receiving end, the actual frequency of an AC bus bar at a wind farm side, the actual voltage at a DC side of a receiving end converter station are obtained, and the reference voltage at the DC side of the receiving end converter station is determined. Then, the voltage of DC line, the frequency of AC bus and the active power of wind farm are controlled separately, which has high reliability, short frequency modulation response time and good frequency modulation effect. Virtual synchronous machine droop control is adopted in the sending-end converter station, which improves the response speed of frequency regulation and shortens the time of frequency modulation. The frequency of the alternating current bus on the wind farm side is controlled by fixed frequency control or frequency conversion control, The active power of wind farm is controlled by virtual inertia, which makes the increased or decreased power released or supplemented in time when the flexible HVDC system provides frequency modulation for the receiving AC network, and reduces the risk of HVDC line voltage exceeding the limit, and greatly improves the reliability of HVDC system.

This invention discloses a controller and method to reconfigure the inertia, damping and fault ride-through capability of a virtual synchronous machine (VSM). The virtual inertia is reconfigured via adding a low-pass filter to the torque (equivalently, active power) signal of the VSM and the virtual damping is reconfigured via adding a virtual damper between the VSM voltage and the output voltage sent to the PWM conversion, instead of adjusting the inertia and the damping in the swing equation. The function of the virtual damper is to scale the existing converter-side inductance or to insert the desired inductance into the VSM, which increases the damping. Moreover, the fault ride-through capability of the VSM can be reconfigured to achieve the given fault-current level via reconfiguring the damping and the inertia properly.

The invention discloses a photovoltaic power generation system virtual synchronous machine control method, control device, converter and system. The direct current side, connected with a photovoltaicmodule, of a photovoltaic inverter is connected to energy storage equipment and an energy storage converter; the voltage and current of the photovoltaic module are collected, a maximum power point tracking algorithm is carried out, a direct current voltage target value is obtained, and the energy storage converter is controlled to operate in a constant output direct current voltage mode accordingto the direct current voltage target value; direct current power output by the photovoltaic module is multiplied by the conversion efficiency of the photovoltaic inverter, the SOC optimal regulation power components of the energy storage equipment are superposed as an active power command of the photovoltaic inverter, and the photovoltaic inverter is controlled to operate in a virtual synchronousmachine mode according to the active power command. The application requirement can be met just by needing relatively small battery capacity, so that the maximum power generation capacity of a photovoltaic panel is guaranteed, the available rate and service life of the battery are optimized, and simultaneously, power support is provided for a power grid.

A transfer press machine which can accurately and promptly check interference and can be easily handled is provided. The transfer press machine includes an interference check device including: a data-conversion constituent element storage section which stores a press-side data-conversion constituent element and a transfer-side data-conversion constituent element in a state of being placed in virtual space to have the same relative positional relationship as in real space; a virtual press operation control section which causes the press-side data-conversion constituent element to perform a virtual press operation in the virtual space according to a press motion; a virtual transfer operation control section which causes the transfer-side data-conversion constituent element to perform a virtual transfer operation in the virtual space according to a transfer motion; a virtual synchronization timing information generation-output section which generates and outputs virtual synchronization timing information, and a virtual interference determination section which determines whether or not interference occurs between the press-side data-conversion constituent element and the transfer-side data-conversion constituent element during a transfer press cycle.

The invention discloses a fuzzy-control-based virtual synchronous motor's virtual inertia adaptive regulation method and a frequency control method. The method comprises the following steps: targeted to the micro source of a currently available micro power grid utilizing the virtual synchronous motor control technology for inversion output, using the output frequency error and the error variation rate of the micro source as the fuzzy output; and based on a two-dimensional fuzzy principle, dynamically adjusting the virtual inertia time constant. The invention further provides a frequency control method, comprising: in combination of the mechanical equation of a virtual synchronous motor, adjusting the output frequency of the virtual synchronous motor to strike a balance between the frequency support and dynamic response in its involvement in the concrete frequency adjusting process, to reduce load switching and the frequency fluctuation rising from micro source grid connecting and to ensure the stable frequency and rapid response of the micro power grid under the islanding state.

The invention provides a method for conducting virtual simulation on a breaker assembly robot. The method comprises the steps that relevant information of a breaker assembly production line is collected to be guided into preset model software, a physical model of the breaker assembly production line is built, and the assembly time and sequences of all components are determined; according to assembly information, logical models of all mechanical assembly devices in breaker assembly are designed based on a Petri network; a mechanical arm three-dimensional model, adapting to the breaker assemblyinformation, of the assembly robot is built, and motion parameters of mechanical arms are calculated to build a motion model; and the motion parameters are subjected to motion simulation, reasonability of model parameters is ensured, and finally a breaker assembly model and the mechanical arm model are introduced into a unity3d scene to achieve virtual motion of the breaker assembly robot. According to the method, the motion parameters of the mechanical arms are solved based on inverse kinematics, through the Petri network, the logical relationship is built, and a virtual assembly system is built for motion simulation of the breaker assembly robot to achieve synchronous-interaction-type display of reality and virtuality.

The invention discloses a control structure and method for a virtual synchronous machine of a voltage source converter based high voltage direct current (VSC-HVDC) system. The control structure comprises a VSC virtual synchronous machine, wherein the VSC virtual synchronous machine is connected with a power grid through a grid-connected gateway KS. The control system of the control structure comprises an active power regulation module, a reactive power regulation module, a mechanical module and an electrical module. By inertia and impedance characteristics of a VSC simulation synchronous power generator and functions of frequency regulation and voltage regulation, the stability of an AC power system is improved, and seamless switching of grid-connected and island modes is achieved. The method comprises a DC voltage control method and an active power control method, can be used for all VSC applications in the VSC-HVDC system and has the function of coordinated control on a DC voltage, and the running reliability of a DC system is improved.

The invention relates to a control method of a microgrid bidirectional converter based on a virtual synchronous machine and stability analysis thereof. An integrator is added in a damping link of a rotor motion equation, and an angular frequency deviation value is fed back and compensated, so that the error-free control of alternating current subnet frequency in a microgrid off-grid mode is achieved. In consideration of the bidirectional transmission characteristic of the converter, a control target is switched into a direct-current voltage from an alternating-current frequency in real time bychanging a virtual mechanical active power reference value given mode, and stable control of direct-current bus voltage is achieved. By establishing a power inner ring and a voltage/frequency outer ring small signal model, transfer functions of the converter in a frequency control mode and a direct current voltage control mode are respectively solved, and stability analysis is performed. The control method of the microgrid bidirectional converter based on a virtual synchronous machine and the stability analysis thereof can well achieve the frequency error-free adjustment of the frequency andthe stable control of the direct current voltage under the off-grid mode.