63results about How to "Reduce frequency deviation" patented technology

The invention discloses a high-energy-efficiency low-jitter single loop clock data recovery circuit. The circuit comprises an 1/N rate Bang-Bang phase discriminator with a 1:N demultiplexer function, a voltage-current converter, a loop filter and a multi-phase clock generator. An orthogonal clock signal generated by an orthogonal voltage control oscillator in the multi-phase clock generator is synthesized into a needed (N+2) phase recovery clock signal through a cascaded digital phase interpolator. And then the 1/N rate Bang-Bang phase discriminator receives input data and a phase clock signal, detects a phase relationship between the two to generate a lead/lag voltage signal and recovers N paths of parallel 1/N rate data signals. Then, the lead/lag voltage signal is converted into a current signal through the voltage-current converter. A current passes through loop filter filtering and then controls an output clock frequency and a phase relationship of the multi-phase clock generator so as to reduce a frequency deviation so that phase locking of a clock data recovery loop is reached. Jitter performance of the clock data recovery loop is effectively improved.

The invention discloses an active power control method for wind power plant participated power grid frequency modulation. Wind turbine units are divided into a critical unit, a low air speed unit and a high air speed unit according to the operating conditions of the wind turbine units; the active dispatching power is modified according to the real-time frequency deviation and the active power adjustable value of the wind power plant to obtain active power modification values of the wind power plant participated power grid frequency modulation; and then the active power modification values are allocated to each wind turbine unit of each type according to the types of the wind turbine units to enable the wind turbine units of each type to participate in the frequency modulation based on a certain sequence. According to the active power control method, the wind power plant is taken as the object and the wind power plant participates in the power grid frequency modulation within a certain frequency deviation; the active power control method considers the reasonable distribution of the frequency modulation amount among the units according to the different operating conditions of the units and the active adjustable amount of the wind turbine units; and therefore, the wind power plant can make response rapidly, and the power grid frequency deviation can be reduced to the greatest extent.

The invention relates to a multi-domain electric power system load frequency control method with wind storage. The method comprises the following steps of S1, constructing a multi-domain electric power system and establishing a mathematic model of an electric generator; S2, establishing a state model containing an uncertain item; S3, designing a sliding mode surface; S4, designing a sliding mode load frequency controller; S5, carrying out interval division on an electric power system load and providing different control strategies aiming at loads in different intervals. Compared to the prior art, by using the method of the invention, an energy storage subsystem is participated in system frequency adjusting, and the uncertain item of a parameter in an interconnection system and a control channel time delay problem of an energy storage system are considered. According to an interval of a system load disturbance change, the different control strategies are provided, and the method possesses advantages that a system frequency offset and system overshoot are low; a time terminal is adjusted and electric power system stability is high. Compared to a system with energy storage under traditional PI control, by using the method of the invention, a capacity of energy storage equipment is reduced and investments of the electric power system are decreased.

The invention relates to a multi-area power system load frequency control method. A power system comprises a plurality of areas interconnected by connecting lines; and each area comprises a conventional generator, a super capacitor, a battery energy storage system and a wind generator. The multi-area power system load frequency control method is characterized by comprising the step of: according to a control interval in which a value of an ACE (Area Control Error) is positioned, enabling output power of a frequency regulating device to be correspondingly regulated, and enabling a system frequency error to be kept in a normal range. Compared with the prior art, according to the multi-area power system load frequency control method disclosed by the invention, different control strategies are adopted according to the control interval of the ACE. The control strategies effectively reduce a system frequency error, improve stability of the power system and reduce cost of power grid construction.

The present invention relates to a load-frequency control method of a multi-domain time-lag electric power system with high wind energy permeability. The method comprises the following steps: S1, establishing a time-lag electric power system with multiple domains, and establishing the mathematics model of each generation system; S2, establishing state models with uncertain items corresponding to each domain according to the mathematics model of a generator; S3, designing an integration type sliding mode surface [Sigma]I (t) according to the state models with uncertain items; S4, designing the sliding mode load frequency controller according to the integration type sliding mode surface [Sigma]I (t); and S5, taking a controller ui(t) obtained in the step S4 as a controlling instruction, and optimizing the load frequency offset of the electric system. Compared with the prior art, a wind driven generator participates the regulation of the system frequency to tightly cooperate the wind power generation with the traditional fire power generation, and the increment of the output power of each generator is evenly reduced to ensure the power supply and demand balance of each area and effectively reduce the frequency offset of each area.

The present invention discloses a preferred method of a water turbine adjustment system control parameter to carry out preferred selection of a PID control parameter in a water turbine adjustment system. A model is established according to the water turbine adjustment system, then a target function with a PID controller control parameter as a preferred variation is established according to a simulation system, and the preferred method designed by the invention is used to solve the target function to obtain an optimal PID control parameter. According to the preferred method of the water turbine adjustment system control parameter, a novel heuristic optimization algorithm is used to optimize the target function, a better target function value can be searched, and an obtained solution represents a better PID control parameter. According to the better PID control parameter, the frequency deviation of the water turbine adjustment system is small, the adjustment speed is fast, a system response curve is smooth, and the system adjustment quality is high.

The invention relates to a method for designing a frequency controller of an independent micro-grid. The method comprises the following steps of: establishing a mathematical model of a power generation system of the independent micro-grid, wherein the independent micro-grid comprises a photovoltaic power generation system and a diesel engine system hybrid power supply system; establishing a photovoltaic system mathematical model; establishing a diesel engine mathematical model comprising load disturbance; and designing an interference observer and a sliding mode controller. The output power of a diesel engine generator is regulated to reduce micro-grid frequency deviation caused by a load change and the power fluctuation of a photovoltaic system. By a designed sliding mode load frequency compensation controller, the micro-grid frequency deviation can be reduced, the maximal power output of the photovoltaic system is ensured, and the utilization rates of renewable energy sources are increased.

The invention discloses a multi-domain new energy interconnection electric power system and a design method thereof. The multi-domain new energy interconnection electric power system includes three subsidiary electric systems. Each subsidiary electric system includes a turbine and a cell, a first area subsidiary electric system uses a non-reheating type steam turbine, and the second and third subsidiary electric systems use reheating type steam turbines respectively. The frequency control is optimized by means of a slip form control method which is a typical non-linear control method, and using the slip form control method, each area is integrally modeled and is subjected to decentralised control, the response speed is fast, and the robustness is good. By means of the smooth output power of an energy-storage module, the frequency offset of the system can be finally reduced.

The invention discloses an optimal selection method for new energy mixed system control parameters, and is used for carrying out optimal selection on PID control parameters in a new energy mixed system. A model is established according to the new energy mixed system; and then an objective function with PID controller input and output parameters as state variables is established according to a simulation system; and optimal PID control parameters are obtained by means of solving the objective function through utilization of the optimal selection method designed in the invention. The optimal selection method for new energy mixed system control parameters of the invention employs a novel heuristic optimization algorithm to optimize the objective function, and better objective function values can be searched, so that obtained solutions represent better PID control parameters. The better PID control parameters enable the frequency offset of the new energy mixed system to be smaller, the adjusting speed to be faster, the system response curve to be more smooth and the system adjusting quality to be higher.

The invention provides a detection control flow of special equipment for an electronic detonator. The equipment is connected with the electronic detonator through a lead. The equipment executes a process of new detonator detection to determine that a new detonator is successfully connected to the equipment; a current detection process is executed to detect electrical properties of the new detonator, so as to determine whether a wire current increment caused by the detonator is within an allowed scope of a detonator working current; an identity code detection process is executed to determine whether an identity code form and identity code information of the new detonator are qualified; a function detection process is executed; one or more processes of a detonator self-detection process, a clock frequency detection process and a detonator cipher detection process are executed to detect detonator functions. According to the technical scheme, determination of detonator eligibility is realized; the detection to the detonator of the scheme is more complete, so as to further ensure security, reliability and accuracy of the detonator product during usage, and raise detection efficiency.

The invention discloses an improved additional frequency control method suitable for a double-fed wind-driven generator set to participate in system frequency adjustment in a short-circuit fault in the field of new energy technology. In view of the conventional additional frequency control of a DFIG unit is only suitable for frequency fluctuation caused by a sudden load change and makes it difficult to satisfy the frequency adjustment in the whole process from the occurrence of the short-circuit fault to the elimination of the fault, the wind-driven generator set uses MPPT control when the power grid is in normal operation, and uses the conventional additional frequency control in response to a system frequency change, and improves the transient stability of the system frequency when the system has a load fluctuation. When a transmission line has a fault, according to the change law of the system frequency in the whole process from the occurrence of the short-circuit fault to the elimination of the fault, the parameters in the conventional additional frequency control of the DFIG unit are corrected, so that the output of the DFIG unit is quickly adjusted according to the system frequency change, thereby maintaining the effective inertia damping characteristics of the DFIG unit in the whole process and improving the dynamic response characteristics of the system frequency.

The invention discloses an AHP (analytic hierarchy process) and GA (genetic algorithm)-based parameter optimization method applied to the participation of an energy storage device in power grid frequency modulation. The method includes the following steps that: the energy storage device and a controller thereof are added into a regional frequency modulation model; the analytic hierarchy process is utilized to determine the weight of the factors of the controller that influence a control effect, so that a fitness function can be obtained; the genetic algorithm is utilized to optimize control parameters, so that optimized parameters can be obtained; and the optimized parameters are screened according to the fitness function, optimized individuals are obtained; and the optimized individuals are transported to the energy storage device to control the output power of the energy storage device. According to the AHP (analytic hierarchy process) and GA (genetic algorithm)-based parameter optimization method applied to the participation of the energy storage device in power grid frequency modulation of the invention, an energy storage device assisted AGC frequency modulation mode is adopted, and therefore, frequency modulation performance can be effectively improved, frequency disturbance can be suppressed effectively, the frequency deviation of a system can be effectively reduced, and adjustment time can be shortened; and the analytic hierarchy process and genetic algorithm are adopted to set the parameters of the controller, so that high accuracy and high flexibility can be realized.

The invention relates to a multi-photovoltaic solar-diesel hybrid system coordination control method based on a disturbance observer. A solar-diesel hybrid system comprises a diesel power generation system and a multi-photovoltaic system which contains a center reference command and a local reference command, a loading value in the system is estimated by the disturbance observer, changed values of loads in a hybrid power system are applied to setting of output power reference values of various photovoltaic systems, the photovoltaic output power can be timely adjusted according to changes of the loads, and frequency deviation can be reduced. Effects of the method are compared with those of a multi-photovoltaic power supply system with photovoltaic systems which are not coordinated and totally use maximum power to perform tracing control, a simulation result proves that the method can reduce the frequency deviation of the solar-diesel hybrid system, and each photovoltaic system can obtain high power output.

The invention discloses a control method and system of a cooking device, and the cooking device. The control method of the cooking device comprises the following steps of gradually reducing resonancefrequency of a resonant module from a range upper limit to a range lower limit in a preset frequency detection range; detecting real-time voltage of the resonant module; determining the optimal resonant working frequency of an ultrasonic resonator according to the real-time voltage; and performing ultrasonic cooking according to the optimal resonant working frequency. Through the control method ofthe cooking device disclosed by the invention, the ultrasonic resonator can be located in the optimal working state, and the working efficiency of the ultrasonic resonator is improved. The optimal resonant working frequency is searched in the relatively small frequency detection range, thereby avoiding the large noise produced when the optimal resonant working frequency is searched; and the control method has the advantage of small noise when the optimal resonant working frequency is searched, and the influence on a user by the noise is effectively reduced.

The invention discloses a cooking device control method, a cooking device control system and a cooking device, wherein the cooking device control method comprises the steps of controlling the resonantfrequency to be increased to the first frequency from the pre-set frequency, so that the optimal resonant working frequency of an ultrasonic oscillator can be searched in the range from the pre-set frequency to the first frequency, wherein the first frequency is less than the upper limit value of a pre-set frequency detection interval; if the first frequency is the optimal resonant working frequency of the ultrasonic oscillator, controlling the resonant frequency to be increased to the second frequency from the first frequency, so that the optimal resonant working frequency of the ultrasonicoscillator can be searched in the range from the first frequency to the second frequency; and, performing ultrasonic cooking at the optimal resonant working frequency, wherein the second frequency isgreater than the first frequency, and less than the upper limit value of the pre-set frequency detection interval. By means of the cooking device control method in the invention, the ultrasonic oscillator can be in the optimal working state; furthermore, the noise is relatively low when the optimal resonant working frequency is searched; and influences of the noise on a user are effectively reduced.

The invention discloses a wind-light fuel cell microgrid frequency control method based on robust firefly particle swarm hybrid optimization. The method comprises the following steps of step 1, distributed power supply modeling, 1.1 a wind/light/fuel cell/diesel generator model; 1.2, an energy storage system model, extra electric energy generated in a non-peak period or when the solar energy intensity and the wind speed are higher can be stored in energy storage equipment such as a flywheel, a battery or a super capacitor, and the stored electric power can be reused in a peak load period or ina period that wind energy and photovoltaic power generation are not enough; step 2, constructing a microgrid model for frequency control; and step 3, carrying out FFPSO hybrid optimization PID control. According to the method, frequency deviation of the microgrid under different operation conditions (such as wind speed change and load demand change) is minimized.

The invention relates to a frequency adjustment method and device for a crystal oscillator, a storage medium and electronic equipment. The frequency adjustment method comprises the following steps: acquiring current frequency offset estimation; carrying out smoothing processing on the current frequency offset estimation to obtain smoothed frequency offset estimation; smoothing the variance of thecurrent frequency offset estimation to obtain a smoothed frequency offset estimation variance; and determining a frequency offset adjustment amount according to the smoothed frequency offset estimation and the smoothed frequency offset estimation variance. Therefore, under different frequency offset estimation conditions, the frequency offset of the crystal oscillator can be steadily and effectively controlled within a small range, and the throughput rate and the performance of the system are improved.

Utilizing surface wave device in SH type with its electrode made from aluminum, which is difficult to induce deviation of frequency characteristic caused by deviation of film thick of electrode, the invention provides elastic surface wave device with large electromechanical coupling factor k2 and large reflection coefficient. An electrode constituted from aluminum is formed on crystal base plate with Eulerian angle being as 0 degree, 90-150 degree, 90 minus or plus 5 degree. Normalized film thick H/ lambda is in region 0.04-0.18. The electrode possesses fork finger electrode and reflector, and their metal coating ratio is in region 0.53-0.37.

The invention discloses a wireless communication equipment frequency matching method, a wireless communication equipment frequency matching module and a wireless communication equipment frequency matching system. The method comprises the following steps: determining a plurality of to-be-matched frequency points of two pieces of interactive equipment; controlling one piece of interactive equipment to transmit a request signal to the other piece of interactive equipment at each to-be-matched frequency point; if one piece of interactive equipment receives a response signal fed back by other piece of interactive equipment, recording a frequency point corresponding to the response signal; and determining the frequency for communication of the two pieces of interactive equipment according to the recorded frequency point. According to the invention, the frequency deviation of transmitting and receiving signals of the two pieces of communication interactive equipment can be reduced and the communication effect can be improved.

The invention discloses a wind farm blackstart frequency control method based on virtual inertia, comprising the steps: 10), using a wind farm as a blackstart power source when a system is powered off; 20), powering a wind farm side bus through a diesel generator; 30), powering an auxiliary unit system of a permanent magnet direct-driven wind turbine unit; 40), in a start phase, introducing a system frequency deviation at a turbine side converter control process by using tracking curve switching virtual inertia control method; 50), switching the current main frequency control method to the additional power outer ring virtual inertia control method to respond to the frequency by using a coefficient conversion-based method for main frequency control method smooth switching; 60), starting an opposite thermal power plant auxiliary unit; 70), stating a high-capacity thermal power generating unit to restore a grid to the outside. This method enables frequency stability of an isolated system in the blackstart process of a wind farm to be improved.