159results about How to "Improve frequency stability" patented technology

The invention relates to a shared energy storage virtual inertia compensation control method for wind power cluster collection, and belongs to the technical field of power system control. In order to solve the problem of insufficient cooperative control of a wind power system and an energy storage system in the prior art, a dynamic model is established by obtaining operation parameters, and the dynamic model comprises a wind turbine generator active power control model and an energy storage system charging and discharging model; designing a virtual inertia control strategy, and introducing virtual inertia control to simulate inertia response characteristics of the synchronous generator; shared energy storage coordination control is carried out, and a strategy is designed by using an MPC method according to an inertia demand and an SOC state; establishing a frequency dynamic response model and calculating inertia response time as a virtual inertia control start-stop condition; and optimizing controller parameters and designing locking logic by adopting an intelligent algorithm. The method can improve the system performance and efficiency, enhance the frequency stability, improve the energy utilization efficiency of the energy storage system, optimize the system performance, and improve the system stability and reliability.

A self-adaptive control technology for rotational inertia and damping coefficient of an optical storage VSG system comprises a grid-connected system overall structure which is provided with an energy storage device, takes photovoltaic as a source end and is controlled by a grid-connected inverter virtual synchronous machine, and the grid-connected system overall structure is formed by electrically connecting a photovoltaic array, the energy storage device, an inverter, a DC / DC (Direct Current / Direct Current), a converter and a filter; the energy storage device is additionally arranged at a direct current bus of the system, the energy storage device and the photovoltaic array form a common direct current bus structure, the inverter is controlled by a virtual synchronous machine, inertial response and frequency adjustment are provided for the optical storage power generation system, and the power shortage between the photovoltaic array and the photovoltaic inverter is made up by adding the energy storage device; and the frequency deviation and the frequency change rate are introduced into VSG parameters, and the inertia and damping parameters of the VSG system are adaptively adjusted, so that the frequency stability of the micro-grid during power sudden change is improved, and the direct-current measurement energy storage power balance is met.

The invention discloses an adaptive virtual inertia control method for an inverter based on an Andronov-Hopf oscillator, and relates to the technical field of network-forming inverter control. The invention aims to solve the problem that the stability and reliability of a power system can be damaged by control based on an oscillator. According to the invention, the difference between the output current of the inverter and the reference current is obtained, and the difference passes through an inertia link to obtain an input current error signal of the oscillator; the difference between the active power reference value and the actual value of the inverter is obtained, and the difference is subjected to active-frequency control with self-adaptive virtual inertia to obtain the angular frequency of the oscillator; the reactive power reference value and the actual value of the inverter are subtracted, and the difference value is subjected to reactive-voltage control with a PI controller to obtain the voltage amplitude of an oscillator; the voltage generated by the Andronov-Hopf oscillator is calculated through the Andronov-Hopf oscillator, the voltage passes through the integrator to obtain SVPWM reference voltage, the three-phase voltage source inverter is modulated, and grid-connected control is achieved.

The invention belongs to the technical field of wireless communication, and discloses a communication and perception integrated system applied to speed measurement and distance measurement, which comprises a transmitting end, a transmission end, a communication receiving end and a perception receiving end, the method comprises the following steps: firstly, combining a bilinear frequency modulation signal with a probabilistic shaping 64-order quadrature amplitude modulation signal PS-64QAM; and then, based on a photon-assisted technology, constructing a terahertz frequency band communication sensing integrated system, and simultaneously realizing distance measurement, speed measurement and communication functions. According to the communication and sensing integrated system applied to speed measurement and distance measurement, PS64QAM-DLFM terahertz sensing integrated signals are generated through the time division multiplexing technology and the photon-assisted technology, the system has the high-speed communication function, the high-precision distance measurement function and the speed measurement function with a certain capacity at the same time, the sensing aspect is benefited from the bilinear frequency modulation technology, and the speed measurement accuracy is improved. Accurate measurement of the distance of a high-speed moving target is realized, and the problem of fuzzy distance and speed combined measurement in a sensing integrated system is solved.

A 2-micron large-energy solid two-way amplifier based on a single-frequency pulse optical fiber preceding stage can make full use of the small signal amplification capacity of optical fiber laser and the energy extraction capacity of solid laser, and meanwhile the problem that energy is difficult to improve due to the stimulated Brillouin scattering effect in an optical fiber is solved. And high-stability, high-repetition-frequency and large-energy single-frequency pulse laser output can be realized. The all-fiber cascade amplifier comprises an all-fiber cascade amplifier and a solid two-way amplifier, according to the all-fiber cascade amplifier, a continuous narrow-linewidth fiber laser is adopted as a seed source, continuous light is modulated into pulse light through an acousto-optic modulator, and the waveform, the pulse width and the repetition frequency of output pulse laser are adjusted; the modulated pulse light adopts a main oscillation power amplification structure and is preliminarily amplified by a polarization maintaining optical fiber amplifier; the solid-state amplifier adopts a two-way amplification structure, and further high-efficiency amplification is realized through solid-state two-way amplification. The whole laser system is compact in structure, stable, adjustable in parameter and capable of meeting application requirements of different scenes.

The invention relates to the technical field of power system automation, and particularly discloses a Bayesian optimization setting method for virtual inertia control parameters of a wind turbine generator, and the method comprises the following steps: constructing a disturbed performance index after a power system suffers from an expected fault; constructing a virtual inertia configuration optimization model of the new energy power system by taking the disturbed performance index as an optimization objective function; introducing a constraint condition into a target function in a penalty function form, and converting the virtual inertia configuration optimization model of the new energy power system into an unconstrained optimization model; and iteratively solving an optimal solution of the unconstrained optimization model by adopting a Bayesian optimization algorithm based on a Gaussian process. The method has the advantages that by optimizing the virtual inertia control parameters of the new energy unit, the power angle stability and the frequency stability of the new energy power system under anticipated faults such as an alternating current fault and generator off-grid are improved, and safe and stable operation of the novel power system with new energy as a main body is powerfully guaranteed.

The invention discloses a network construction type fan frequency support control method, device and equipment and a medium, and the method comprises the steps: after obtaining disturbance information, determining an active power reference value of a virtual synchronous machine based on the disturbance information and a frequency response model of a network side converter, and then obtaining a power reference value of a fan side converter based on the disturbance information; the grid-side converter adjusts the fan according to the active power reference value of the virtual synchronous machine, and the machine-side converter adjusts the fan according to the power reference value of the machine-side converter; therefore, when the system is disturbed, the grid-side converter slows down the disturbance degree under the direct voltage control and the virtual synchronous control, and then in order to eliminate the disturbance, the machine-side converter adjusts the active power output instruction of the fan according to the disturbed information, so that the frequency stability of the system is effectively improved.

The invention discloses a model library-based spaceflight radio frequency signal quality multi-domain evaluation and compensation method, and belongs to the technical field of wireless communication. The implementation method comprises the steps of determining signal system parameters based on various CCSDS standards and a spaceflight protocol system, extracting related parameters of spaceflight standards in a time-frequency domain, generating standard time-frequency domain radio frequency signals, converting the standard time-frequency domain radio frequency signals into a related domain, a modulation domain, an energy domain and a polarization domain, and establishing spaceflight radio frequency signal sub-model libraries of the domains; obtaining a time-frequency domain measured signal through a receiver, integrating time domain information and frequency domain information, and constructing a time-frequency domain sub-evaluation model; constructing a multi-domain comprehensive evaluation model by adopting a parallel data transmission mode and a weight data processing method; calculating the weight of the evaluation result of each domain through an entropy weight method, and obtaining a comprehensive quality evaluation result of the spacecraft radio frequency signal; and based on the distortion coefficient, a robust signal equalization algorithm is adopted to process the signal, the influence of the distortion effect on the signal quality is compensated, and the robustness and the anti-interference capability of signal transmission are improved.

The invention provides BCZT-BNT-based lead-free composite energy storage ceramic with high breakdown strength and a preparation method of the BCZT-BNT-based lead-free composite energy storage ceramic, and belongs to the field of dielectric energy storage ceramic materials. The general formula of the chemical composition is (1-x) [0.25 (Bi < 0.5 > Na < 0.5 >) TiO < 3 >-0.75 Ba < 0.85 > Ca < 0.15 > Zr < 0.1 > Ti < 0.9 > O < 3 >]-xBaZrO < 3 >, and x is the mole number and ranges from 0.05 to 0.20. According to the preparation method disclosed by the invention, chemical component disorder is induced by doping modification on an atomic scale, and a high-dynamic-polarity nano micro-region (PNRs) is formed, so that the nano micro-region has an obvious dielectric relaxation behavior and a slender ferroelectric hysteresis loop (P-E ring), and the energy storage ceramic material with high energy storage density and energy storage efficiency, ultrahigh breakdown strength and excellent frequency stability is obtained.

The invention discloses an optimal unit combination method and device considering inertia-frequency change rate spatial distribution characteristics, and the method comprises the steps: expanding a conventional DC power flow model to a node behind the internal reactance of a generator; inertial response process models of different nodes are constructed, and the injection power and phase angle change coupling relation of the generator nodes and the load nodes at the moment after disturbance is analyzed; establishing an inertia-frequency change rate spatial distribution model according to the characteristics of different nodes; and combining the inertia-frequency change rate spatial distribution model established in the previous step, comprehensively considering spatial characteristics and inertia distribution conditions of the power grid topology, and constructing an optimal unit combinatorial scheduling model based on meeting power grid node frequency security constraints and steady-state constraints. According to the invention, the frequency stability of the system after major disturbance is improved.

The invention relates to the technical field of unit control, in particular to a control method, system and equipment based on lithium battery energy storage and a medium, and the method comprises the steps: obtaining power grid characteristic parameters, and determining a target transfer function expected to be realized; constructing a power grid frequency response model based on lithium battery energy storage, and solving a target transfer function according to the power grid frequency response model under the condition that a set power grid system frequency response index and frequency adjustment time are used as constraint conditions; deducing a frequency modulation transfer function of the energy storage system according to the target transfer function and the synchronous machine transfer function; and obtaining a control instruction of the energy storage system by using the transfer function, and responding to the power grid according to the control instruction. The method effectively solves the problems of stability and reliability of the lithium battery energy storage system in control.

The invention discloses a shared energy storage frequency adjusting method and system based on deep reinforcement learning. The frequency regulation method comprises the following steps that an LFC model of multiple microgrids is established, frequency response and power balance under physical constraints and frequency modulation constraints of the multiple microgrids are simulated according to the LFC model, and the multiple microgrids comprise a shared energy storage system; establishing an objective function satisfying the power balance in consideration of the frequency response and the cost; and establishing a frequency modulation framework based on intelligent power generation control of the DRL, generating a control instruction meeting the target function according to the state information of the LFC model based on a Markov decision, and executing the control instruction by the frequency modulation framework to perform frequency modulation. The method is specially used for the micro-grid with the shared energy storage system, aims to improve the performance and economical efficiency of frequency regulation through an intelligent optimization algorithm, and has the characteristics of cost reduction and high efficiency.

The invention discloses a lead-free energy storage ceramic laminated material, and belongs to the technical field of dielectric energy storage. The lead-free energy storage ceramic laminated material is formed by sequentially laminating lead-free energy storage ceramic with a texture structure and lead-free energy storage ceramic with a non-texture structure, and preferably, the material comprises at least three layers; when the lead-free energy storage ceramic with the texture structure is positioned on the middle layer, the lead-free energy storage ceramic with the non-texture structure is positioned on the two sides of the middle layer; when the lead-free energy storage ceramic with the non-texture structure is located on the middle layer, the lead-free energy storage ceramic with the texture structure is located on the two sides of the middle layer. Based on the structural design of at least three layers, the non-textured ceramic is selected as the high-voltage-resistant layer, the textured ceramic is selected as the high-polarization layer, the lead-free ceramic laminated material with excellent energy storage performance is obtained, and the lead-free ceramic laminated material has wide application prospects in the fields of power electronics and pulse power.

The invention relates to a sensing system based on a surface acoustic wave oscillator. The sensing system comprises two resonators, two oscillating circuits, a temperature controller, a fluid pipeline, a frequency mixer, an amplification function comparator and a frequency divider, the temperature controller, the resonators and the oscillating circuits are arranged on the fluid pipeline, the two resonators are located on the upper side and the lower side of the temperature controller respectively, and the two oscillating circuits are located on the upper side and the lower side of the two resonators respectively; the temperature controller transmits heat to the resonators on the upper side and the lower side through the fluid pipeline, the resonators adjust resonant frequencies according to temperature changes and output different frequencies to the adjacent oscillating circuits, and the two oscillating circuits are connected with the frequency mixer. The mixer outputs a difference frequency signal to the amplification function comparator, and the amplification function comparator outputs a square wave signal to the frequency divider.

The invention discloses a parameter adaptive control method and device for frequency modulation participation of a network construction type wind power plant. The method comprises the following steps: respectively establishing an inertia adaptive curve model and a droop adaptive curve model of each wind turbine generator set; distributing a corresponding cooperative control coefficient for each droop adaptive curve model to obtain a droop adaptive curve cooperative control model of each wind turbine generator set; in the frequency modulation process from power disturbance to maximum frequency deviation of the system, the inertia coefficient and the droop coefficient of each wind turbine generator set are respectively changed according to the corresponding inertia adaptive curve model and the corresponding droop adaptive curve cooperative control model; in the frequency modulation recovery process after the system has the maximum frequency deviation, the inertia coefficient of each wind turbine generator set is maintained at the set minimum inertia coefficient, and the droop coefficient of each wind turbine generator set continues to change according to the corresponding droop adaptive curve cooperative control model; therefore, cooperative control of each wind power set in the wind power plant participating in system frequency modulation is completed.

The present disclosure provides an electrostatic MEMS resonator with low dynamic resistance, comprising: a first resonance unit, which is a ring structure; a first support unit, one end of which is connected to the first resonance unit, and the other end is connected to the first base; wherein the length of the first support unit is equal to one quarter of the resonance wavelength of the electrostatic MEMS resonator; a pair of electrodes, comprising: a first electrode and a second electrode, the first electrode is located on the inner side of the first resonance unit, and the second electrode is located on the outer side of the first resonance unit; wherein the first electrode and the second electrode are respectively spaced apart from the first resonance unit by a first gap layer. The present disclosure also provides an electrostatic MEMS resonator array with low dynamic resistance.

The invention provides a frequency inertia cooperative control method and device for a distributed new energy cluster, and relates to the technical field of power grids. According to the method, the frequency deviation and the frequency change rate of each monitoring point are obtained by analyzing the power grid operation data, then the active power adjustment amount of each monitoring point is determined, and power distribution is performed on the active power adjustment amount in combination with each function group in the distributed new energy cluster. And a cooperative control scheme of the quick response group, the continuous support group and the standby group is determined, active power adjustment is performed on the distributed new energy cluster, and frequency inertia support is realized. Through cooperative control of the active power of the distributed new energy cluster, active output of the photovoltaic unit, the wind power unit and the energy storage unit is cooperatively changed, frequency inertia support of the power grid is realized, and the frequency stability of the power grid is improved.

The invention discloses a high-proportion power electronic system networking converter demand evaluation method, which comprises the following steps: expressing a dynamic relationship between active power and frequency after a system is disturbed through a synchronous machine rotor motion equation to obtain an active power-frequency dynamic model, and obtaining system equivalent inertia according to the model; establishing a system frequency dynamic response model, and calculating to obtain the minimum inertia requirement of the system considering the frequency shift rate and the maximum frequency deviation constraint; the equivalent inertia of the system is expressed by adopting the weighted average of each inertia source, and the comprehensive inertia of the system is increased by increasing the number of the network-forming converters so as to meet or exceed the minimum inertia requirement of the system. The method has the beneficial effects that the requirements of the network construction type converter under different power system conditions can be accurately evaluated, and the system can still be kept stable when subjected to frequency disturbance.

The invention relates to the technical field of oscillators, and discloses a low-noise broadband voltage-controlled oscillator based on a cross coupling differential structure, which comprises a resonant cavity, a differential negative resistance circuit and a current bias circuit, and is characterized in that the resonant cavity adopts an LC resonant structure and is used for determining frequency selection and phase characteristics of the low-noise broadband voltage-controlled oscillator; the differential negative resistance circuit adopts a cross coupling differential pair structure formed by two bipolar junction transistors and is used for providing enough gain and positive feedback so as to generate a negative resistance effect; the current bias circuit uses a bipolar junction transistor to construct a bias circuit structure and is used for providing stable bias current and ensuring that the bipolar junction transistor in the differential negative resistance circuit works in an amplification region.

The invention relates to the technical field of power systems, and discloses a half-wavelength controllable tuning method under the background of a dual-carbon and novel power system. Comprising the following steps: system evaluation and demand analysis: collecting power grid information and fusing dual carbon and novel power system demands to determine a tuning target and key parameters; designing a half-wavelength tuning strategy, determining tuning parameters by using a particle swarm optimization algorithm, formulating the strategy, and performing simulation optimization; selecting and configuring half-wavelength controllable equipment, evaluating performance indexes, selecting equipment, and reasonably configuring, installing and debugging; system integration and communication network construction: integrating equipment and constructing a reliable communication network to ensure information transmission; tuning implementation and monitoring are carried out, a control system is developed to send instructions, data are collected and analyzed to evaluate performance, and optimization is fed back according to results. According to the invention, the stability and adaptability of the power grid are enhanced, the intelligent development is promoted, the resource configuration and structure are optimized, the safety and sustainable development are guaranteed, and the challenges of dual-carbon and novel power systems can be effectively handled.

The utility model provides an air-ground cooperative positioning rescue system in the technical field of rescue equipment. The air-ground cooperative positioning rescue system comprises a positioning terminal, a searching terminal, a rescue terminal and an unmanned aerial vehicle, the positioning terminal comprises a first control module and a first GPS positioning module. The search terminal comprises a second control module and a second GPS positioning module; the rescue terminal comprises a third control module, an LED status lamp, an OLED screen, an LTE communication module and an LTE power supply module. One end of the first control module is connected with the first GPS positioning module, and the other end of the first control module is connected with the second control module; the second GPS positioning module is connected with the second control module; the third control module is connected with the second control module, the LED status lamp, the OLED screen and the LTE communication module. The LTE power supply module is connected with the LTE communication module; and the search terminal is arranged on the unmanned aerial vehicle. The positioning rescue device has the advantage that the positioning rescue efficiency is greatly improved.

The invention discloses a power system inertia distribution optimization method and device based on node inertia and a medium. The method comprises the following steps: setting basic parameters; taking minimization of system inertia total cost as a target, and considering upper and lower limit constraints of an equivalent inertia constant of the new energy grid-connected converter, a system frequency change rate constraint and a system inertia space distribution constraint to construct an optimization model M1; solving the optimization model M1 to obtain the total inertia cost of the system; taking maximization of the overall inertia level of the system as a target, and considering upper and lower limit constraints of an equivalent inertia constant of the new energy grid-connected converter, a system frequency change rate constraint, a system inertia space distribution constraint and a system inertia total cost constraint to construct an optimization model M2; and solving the optimization model M2, and outputting the value of the equivalent inertia constant of the new energy grid-connected converter. According to the method, the frequency change rate constraint and the inertia space distribution constraint are considered, efficient solution of inertia distribution optimization of the power system is realized, and the method can be used for improving the frequency stability of the power system.

The invention provides a moss growth-based virtual inertia and damping control method for a grid-forming fan, and the method comprises the steps: determining a frequency deviation value based on the power grid real-time frequency of a power grid system where the grid-forming fan is located and a preset frequency reference value, and determining a frequency change rate based on the power grid real-time frequency; inputting the frequency deviation value, the frequency change rate, a preset virtual inertia initial value and a virtual damping initial value into a network controller pre-constructed based on moss growth; determining a target damping coefficient, a target virtual rotational inertia coefficient and a target proportionality coefficient of a power tracking curve of the power grid system based on a network controller; based on the target proportionality coefficient, determining a first reference value of active power input of the grid-forming type fan and a second reference value of active power input of an energy storage system in the power grid system; and based on the first reference value, the second reference value, the target damping coefficient and the target virtual rotational inertia coefficient, the virtual inertia and damping of the net-forming type fan are controlled, and dynamic adjustment of the inertia and the damping coefficient is achieved.

The invention discloses a high-proportion new energy power grid frequency rotational inertia control method and system. The method comprises the following steps: establishing a virtual rotor motion equation controlled by a new energy grid-connected converter VSG; obtaining an active-frequency droop equation; deriving a mathematical model of the output voltage of the new energy grid-connected converter VSG control system under a dq two-phase coordinate system; calculating the output power of the VSG when the new energy grid-connected converter VSG control system stably operates; an energy composition function is adopted to analyze a transient energy change process when the frequency of the new energy grid-connected converter VSG is adjusted; a novel self-adaptive virtual inertia is obtained; a high-proportion new energy power grid frequency rotational inertia control equation used for reducing the oscillation frequency during frequency adjustment of the new energy grid-connected converter VSG is obtained, and adjustment of the new energy power grid frequency is achieved. According to the invention, a novel VSG control strategy is adopted, the VSG control strategy is improved, the frequency change rate is introduced to represent the virtual inertia, and the adjustment deviation and the adjustment time during the frequency adjustment of the new energy grid-connected converter VSG are reduced.

The invention relates to a satellite-borne clock control method, device and system based on model prediction. The method comprises the following steps: performing state estimation according to a pre-constructed high-precision clock model and historical clock error data to obtain a clock state at each moment in a prediction interval; constructing a quadratic form cost function according to the clock state of each moment in the prediction interval and the weight matrix, minimizing the quadratic form cost function by adopting a rolling optimization method, outputting a control quantity of the current control moment, and optimizing the control quantity by utilizing a differential control quantity and a differential coefficient to obtain an optimal control quantity; obtaining a to-be-adjusted clock error sequence according to clock error data corresponding to a future moment in the prediction interval, performing phase adjustment on the to-be-adjusted clock error sequence according to the optimal control quantity of the current control moment and a time interval of two adjacent clock errors to obtain an adjusted clock error sequence, and iteratively updating the clock error sequence according to a time sequence to realize satellite-borne clock control. By adopting the method, the performance of the satellite-borne secondary frequency standard can be enhanced.

The invention relates to a sending end frequency active support coordination control method for wind power through a high-voltage direct-current delivery system, and belongs to the field of frequency stabilization of large-scale wind power through the high-voltage direct-current delivery system. The method comprises the following steps: firstly, according to unbalanced power caused by power regulation margins and disturbance of various frequency modulation resources, analyzing high-voltage direct current system sending end system frequency support requirements in different scenes; secondly, providing a wind power plant multi-time scale frequency modulation control strategy based on the doubly-fed wind turbine generator and a doubly-fed wind turbine generator and high-voltage direct current system frequency support coordination control strategy considering a frequency modulation dead zone; finally, key control parameters in the control link of the doubly-fed wind turbine generator and the high-voltage direct-current system are designed according to the power regulation margin of the synchronous generator set and the wind power plant, so that inertia support and primary frequency modulation effects can be adaptively switched according to different scenes; the quick response capability of the doubly-fed wind turbine generator and the high-voltage direct-current system is exerted, and meanwhile, the power adjusting capability of each unit is fully utilized.

The invention discloses a double-frequency constant-temperature crystal oscillator and a manufacturing method thereof, and relates to the technical field of crystal oscillators, and the double-frequency constant-temperature crystal oscillator comprises a ceramic base and a ceramic bottom plate which are integrally formed by adopting an LTCC (Low Temperature Co-Fired Ceramic) process; the high-frequency quartz crystal and the low-frequency quartz crystal are respectively arranged in independent closed cavities, and unified heating and accurate temperature control are realized through the high-heat-conduction diamond copper substrate, the metalized heat conduction holes and the partitioned temperature sensing chips; the two paths of signals are output through independent interconnection paths, and the crosstalk is lower than-50dBm. According to the invention, the dual-frequency high-stability low-noise output is realized under the similar volume, and the requirements of a flight control system on a high-integration-level and high-reliability frequency source are met.

The invention discloses a distributed new energy frequency support system based on power grid inertia and frequency modulation demand, and relates to the technical field of power systems, and the system comprises the steps: analyzing the load state of an AC power distribution network, and obtaining a power distribution network state reference characteristic value; analyzing the inertia of the alternating-current power distribution network to obtain an inertia characteristic value; analyzing the fluctuation state of the alternating-current power distribution network, and obtaining a state characteristic value of the power distribution network in combination with the inertia characteristic value; combining the power distribution network state reference characteristic value and the power distribution network state characteristic value, and performing comprehensive analysis to obtain a frequency support characteristic value; based on the frequency support characteristic value, comparing to obtain a primary frequency modulation control scheme of the AC power distribution network; and analyzing the application state of the primary frequency modulation control scheme of the AC power distribution network, and comparing to obtain a secondary frequency modulation control scheme of the AC power distribution network. According to the distributed new energy frequency support system based on the power grid inertia and the frequency modulation demand, the problems of power grid frequency fluctuation and insufficient inertia can be better solved, and safe operation of a power system is ensured.

The invention provides a pulse laser calibration-based high-precision laser ranging system and method. The system comprises a ranging light path and a calibration light path, in the distance measurement light path, an arbitrary waveform generator performs frequency modulation on a laser signal of a semiconductor laser, the laser signal is divided into two beams through an optical fiber coupler, the two beams are respectively incident to a distance measurement unit and a calibration light path, and the distance measurement unit transmits the laser signal to a target for distance measurement; in the calibration light path, a pulse laser emits frequency calibration laser, the frequency calibration laser is transmitted to a second optical fiber coupler, and the frequency calibration laser is coupled with the laser signal to obtain a frequency mixing light signal; and the processor obtains a distance measurement result based on the distance measurement signal, determines a change curve of the laser signal frequency along with time based on the frequency calibration laser, obtains a non-linear quantity of frequency modulation, and calibrates the distance measurement result based on the non-linear quantity of frequency modulation. The pulse laser is used for calibrating the output frequency of the semiconductor laser, the distance measurement result is corrected, and the distance measurement precision is improved.

The invention discloses a frequency modulation capability-considered DC frequency coordination control method, system and device, and the method comprises the steps: calculating the frequency modulation capability coefficient of each DC power transmission system participating in the frequency modulation of a sending-end AC system based on the operation state of each DC power transmission system and the equivalent parameter of a DC receiving-end AC system; based on the frequency modulation capability coefficient and the frequency of the sending end AC system, calculating the frequency modulation auxiliary power of each DC power transmission system of which the sending end is commonly connected to the same sending end AC system; adding the frequency modulation auxiliary power and each initial power to obtain alternative power of each direct current power transmission system; and determining the actual power of each direct-current power transmission system according to the comparison result of the alternative power of each direct-current power transmission system and the minimum operation power limit value and the maximum operation power limit value of each direct-current power transmission system. According to the technical scheme, the problems that the frequency modulation capability of multiple direct-current power transmission systems is not fully played and a certain direct-current receiving end alternating-current system excessively participates in frequency modulation in the prior art can be solved.