45results about How to "Achieving Maximum Power Tracking" patented technology

The invention discloses a variable speed constant frequency wind power generation system integrated with an energy storing device and control methods. A variable pitch draught fan is connected with a variable pump through a coupler, the variable pump, a one-way valve A, a two-position two-way electromagnetic directional valve B, a variable motor and an oil filter are sequentially connected through hydraulic pipelines to form a loop-locked main hydraulic speed regulation loop, the variable motor is connected with a power generator or an electromotor through a clutch A, the energy storing device comprises a pump or a motor and a high-pressure gas storage tank, and the power generator or the electromotor is connected with the pump or the motor through a clutch B. A wind generating set and the energy storing device are integrated, the displacement of the variable pump and the displacement of the variable motor are independently regulated, maximum power tracing of a wind turbine can be achieved, it can be guaranteed that the output rotating speed of the variable motor is constant, the output frequency of the power generator is stable, different control methods are adopted for different types of wind power, the influences of the time and climate change on wind power generation are effectively avoided, the wind energy utilization rate is greatly increased, and wind electricity quality is improved.

The invention discloses a hybrid modulation strategy based power balance control method for a cascade H-bridge inverter and aims to solve a problem of incapability of stable operation of a system due to input power imbalance of a photovoltaic battery panel on a DC side of the photovoltaic inverter. The method includes steps of 1, master DC side voltage control used for realizing maximal power point voltage tracking by H-bridge unit DC side voltages and obtaining a system active current command value; 2, grid side current decoupling control capable realizing independent control of active current and reactive current and generating inverter total modulation wave voltage; 3, inter-unit power balance control including determining the correct switching states of each H-bridge unit so as to realize the power balance control among the H-bridge units and the maximal power tracking of the H-bridge units through DC side voltage error ranking of the H-bridge units. The method can be suitable for different kinds of working conditions. By adopting the method, stable operation of the cascade H-bridge photovoltaic inverter in a comparatively large range and system power generation capacity can be guaranteed.

The invention relates to a self-adaptation sliding mode control strategy for a permanent magnet synchronous wind power generation system. The self-adaptation sliding mode control strategy is technically characterized in that mathematic models of various components of a wind power generation system power generator side are established; an interfered PMSG model with uncertain parameters is established; a Terminal sliding mode surface is constructed; a rotation speed self-adaptation Terminal sliding mode controller is constructed; and a current self-adaptation Terminal sliding mode controller is constructed. On the basis of influences from inherent nonlinearity, uncertainty, outside interference and other factors of the permanent magnet synchronous wind power system, the Terminal sliding mode control theory and the self-adaptation technology are combined, the self-adaptation Terminal sliding mode control strategy is formed, maximum power tracing for a permanent magnet synchronous draught fan is achieved, the maximum wind energy below the rated wind speed can be captured, vibration can be effectively restrained, and good self-adaptability and robustness are achieved.

The invention discloses a solar grid-connected inverter with a maximum power point tracking (MPPT) system. The solar grid-connected inverter comprises a cabinet-type container box body (22) of a metal structure, a door lock (18) and a door (19). Working state indicating lights (17) and an LCD (Liquid Crystal Display) screen (21) are arranged on the surface of the door (19), and a cooling fan (20) is arranged on the lateral face of the box body. The solar grid-connected inverter is characterized in that all unit circuits are arranged in the cabinet container box body of the metal structure, a photovoltaic grid-connected system which takes a DSP (Digital Signal Processing) microprocessor (12) as a main control chip has rapid operational capability and rich peripheral resources so as to provide a favorable platform for the entire control system, and an MPPT control algorithm which has the tacking object of making a load acquire maximum power is adopted to realize the tracking of a maximum power point.

The invention provides a modularized photovoltaic energy storage system, wherein the output ends of energy storage cell units are connected with direct current bus input ends of half-bridge modules to form multiple energy storage cells; the alternating current output sides of the multiple energy storage units are connected in series and then connected with electric reactors in series to form a one-phase half-bridge arm; two half-bridge arms are connected in series to form a one-phase overall bridge arm, and three bridge arms form three-phase bridge arms in the manner; the upper ends of the three bridge arms are connected to form the direct current bus positive end of the photovoltaic energy storage system; the lower ends of the three bridge arms are connected to form the direct current bus negative end of the photovoltaic energy storage system; the connecting points of the upper bridge arm and the lower bridge arm of the three-phase bridge arms, namely the three middle points of the three bridge arms are led out to form an alternating current port of the photovoltaic energy storage system; and the output positive end and the output negative end of a photovoltaic group string are connected with the direct current bus negative end and the direct current bus negative end of the photovoltaic energy storage system for transmitting voltage. The modularized photovoltaic energy storage system is based on a modularized multi-level structure; the modularized photovoltaic energy storage system is provided with the alternating current port, the direct current port and the cell port, so that the modularized photovoltaic energy storage system can be connected with a photovoltaic module, an energy storage cell and an alternating current power grid at the same time.

The invention discloses a piezoelectric expandable energy collection interface circuit based on MPPT. The piezoelectric expandable energy collection interface circuit comprises expandable piezoelectric transducers, expandable peak detection switches, an LC resonant inductor, a rectifying circuit, a rectifying capacitor, a DC-DC conversion chip and an energy storage capacitor, wherein the number ofthe expandable peak detection switches corresponds to the number of the piezoelectric transducers, and the maximum power point tracking (MPPT) module is composed of a peak voltage tracking circuit and a hysteresis voltage comparator. The expandable piezoelectric transducers, the expandable peak detection switches, the LC resonant inductor, the rectifying circuit and the rectifying capacitor forman expandable series synchronous switch inductor energy collection interface circuit. The maximum power point tracking (MPPT) module detects peak open-circuit voltage of the piezoelectric transducersand voltage at two ends of the rectifying capacitor during normal operation of the expandable series synchronous switch inductance energy collection interface circuit, and keeps the voltage of the rectifying capacitor near the maximum output power by controlling the DC-DC conversion chip. The circuit can be completely self-powered, so that the energy collection efficiency is greatly improved.

The invention discloses a wind power generation maximum power tracking method of a speedless sensor. The method comprises the steps of: 1) obtaining maximum wind power through an experiment to capture a relation curve with the rotating speed of a motor; 2) performing the modeling analysis for the electromagnetic torque of a generator; 3) analyzing a transmission chain model in a maximum power tracking state; 4) determining a relation between an optimal output power and synchronous speed of an induction motor, and building a lookup table; and 5) designing an adaptive controller for a system. The method can realize the maximum power tracking of a wind driven generator in low wind speed without measuring the rotating speed of the wind driven generator, the wind magnitude and the direction. As the magnitude and the direction of wind are difficult to be invariable under the influence of various factors, the accurate measuring process is complex, and the system cost is increased. Therefore, the method effectively solves the measuring difficulties in the measurement of wind magnitude and direction in a conventional wind power generation system, and reduces the system cost to a certain extent.

A solar battery array variable step-size MPPT control circuit and a control method, the method comprising a current sampling circuit, an MPPT control circuit, a hysteresis loop comparison circuit, and a step-size switching circuit. The current sampling circuit is used to collect the output current of the solar cell array, and the MPPT control circuit is used to realize the tracking of the maximum power point; the hysteresis comparison circuit is used to increase the anti-interference ability of the step switching circuit; the step switching circuit is used for MPPT tracking step switch. The circuit realizes that when the current of the solar cell array is small, the maximum power point is tracked with a larger step size, and when the current of the solar cell array is large, the maximum power point is tracked with a smaller step size, which improves the maximum power point of the solar cell array Tracking accuracy.

The embodiment of the present invention relates to the technical field of photovoltaic cell manufacturing, and discloses a photovoltaic system and a maximum power tracking method thereof. The photovoltaic system includes: a plurality of photovoltaic cells, and the photovoltaic cells are used to collect solar energy to generate direct current; Both are used to send electrical parameters to the cloud server, and the electrical parameters include at least the first output parameter of the photovoltaic cell and the second output parameter of the optimizer; the cloud server, the cloud server is used to receive the electrical parameters, and according to the electrical parameters Calculate the characteristic physical quantities used to adjust the output power of the photovoltaic cells, and the cloud server is also used to send the characteristic physical quantities to the optimizer; the optimizer is also used to receive the characteristic physical quantities, and adjust the output power of the photovoltaic cells according to the characteristic physical quantities, so as to realize the photovoltaic cell's output power. Maximum power tracking. The photovoltaic system and the maximum power tracking method thereof provided by the invention can realize efficient maximum power tracking of photovoltaic cells, and improve the accuracy and efficiency of calculating the maximum power of photovoltaic cells.

The invention discloses a tidal energy control system, which comprises a tidal energy power generation device, a hardware circuit topology and a control module, and is characterized in that the hardware circuit topology comprises an uncontrolled rectification circuit and a Boost converter circuit, and the Boost converter circuit is connected in parallel with a hybrid semiconductor parallel device; the control module comprises a variable step frequency adaptive filtering controller, a maximum power tracking controller and a high-performance prediction controller. Maximum power point capturing of output power is achieved through a self-adaptive maximum power control strategy, and meanwhile smooth processing is conducted on tidal energy output power on the premise that power is not lost too much; the high-efficiency, low-harmonic-content and high-power-factor operation of the power converter is realized by establishing a cost function containing device loss, harmonic content and power factors through a high-performance predictive control method. Therefore, the tidal power generation device can meet high-performance and high-stability power supply requirements in the island, coast or offshore power generation process.

The invention discloses a photovoltaic cell multiple-peak maximum power tracing method and system based on a particle swarm. The data values of voltage and current output by a photovoltaic cell underthe partial shaded condition are obtained, particles are initialized to a possible voltage value, the maximum power point of the particles is iteratively continually updated, a historical optimal position and a global optimal position of an individual are looked for, therefore, the multi-peak maximum power point obtained under the complicated partial shaded condition is determined, and after a corresponding ending condition is reached, searching of the maximum power point is ended. Compared with a traditional maximum power tracing method, the maximum power tracing method can prevent searchingfrom trapping in local optimum, the tracing precision and speed are ensured, oscillation loss generated in the tracing process is reduced, and the method more conforms to reality.

The invention discloses a method and a system for realizing an optimal value of charging current of a storage battery in an off-network charging system. The method comprises the following steps: A, selecting an initial output current reference value, outputting operation results by a digital regulator, feeding the operation results into a pulse width regulator to generate a control signal, and obtaining an actual output current value by current feedback; B, calculating the change direction of the current according to the actual output current value and the initial output circuit reference value, calculating and updating the current disturbance direction results of next MPPT (maximum power point tracking) by combining the current disturbance direction of this MPPT; C, updating the output current reference value at fixed step length according to the calculated current disturbance direction results of next MPPT, and obtaining maximal charging current by repeatedly updating. According to the method and the system for realizing the optimal value of the charging current of the storage battery in the off-network charging system, measurement for voltage and current signals is cancelled, so that the maximum power tracking of a PV (photovoltaic) component can be realized by only needing to measure the charging current of the storage battery, and therefore, the hardware cost is lowered, and the requirements of processor performances are lowered.