34results about How to "Achieving Maximum Power Point Tracking" patented technology

The invention provides a photovoltaic micro inverter. The inverter comprises a boost module and an inversion module. The boost module comprises a preceding stage DC-DC converter and an after stage DC-DC converter. A photovoltaic array (PV), the preceding stage DC-DC converter, the after stage DC-DC converter and the inversion module are sequentially connected in series. The preceding stage DC-DC converter achieves maximum power point tracking and voltage lifting through a first Boost circuit and a second Boost circuit, the after stage DC-DC converter is responsible for further lifting the voltage so that the power grid grade can be reached, and the maximum power point tracking is achieved while the step-up ratio is larger than 10. According to the photovoltaic micro inverter, the circuit characteristic that switching loss is small is fully utilized, the high-frequency characteristic of a switched-capacitor circuit is played, and the size and output ripples of a filter can be effectively reduced.

The invention discloses a maximum power point tracking controller for a three-phase photovoltaic power generation system. The controller mainly comprises a BOOST type DC/DC converting circuit, a three-phase inversion circuit, a control circuit and a power circuit. The technical scheme includes that a variable-structure fuzzy control method is applied to MPPT (maximum power point tracking) of photovoltaic power generation so that tracking precision can be improved, and the method can effectively realize maximum power point tracking when illumination and temperature vary. By means of variable-structure fuzzy control, different fuzzy sub-controllers are designed according to different working conditions, the discourse domain range, control rules, parameters and the like of the fuzzy sub-controllers are different, the fuzzy sub-controllers form a variable-structure fuzzy controller, and accordingly one fuzzy sub-controller constantly enables the system to achieve the optimal control quality in system running.

The invention discloses a high-efficiency wide-load-range three-phase micro-inverter and a control method thereof. The high-efficiency wide-load-range three-phase micro-inverter includes a front stage DC-DC converting module used for transmitting electric energy output by a photovoltaic assembly and tracking the maximum power point of the photovoltaic assembly; a middle-stage quasi-third harmonic injection circuit used for injecting AC current meeting power grid connection condition obtained through combination of inverted six-pulse DC current output by the front-stage circuit and quasi-triangular wave output by said circuit; a rear-stage bridge-type inverting circuit, filtering circuit and power grid used for performing inversion on current output by a power optimizing module, filtering the current obtained through combination of the inverted current and the quasi-triangular wave output by the quasi-third harmonic circuit through the filtering circuit and injecting the current into the power grid. The invention also discloses methods for analyzing and designing the quasi-third harmonic injection circuit and extracting ad controlling quasi-third harmonic wave injection current reference signals. The three-phase micro-inverter has characteristics of being simple in structure, high in converting efficiency and small in size.

The invention discloses a piezoelectric vibration energy collection system capable of tracing maximum power point. In the piezoelectric vibration energy collection system, a self-power supply SSHI-type AC-DC rectifier is used for converting an alternating current output from a piezoelectric transducer into a direct current, the direct current is output to a first capacitor, a hysteresis comparisoncontrol and working power supply selection circuit is used for controlling whether a PWM wave generation and working mode selection circuit enters a working condition or not, the PWM wave generationand working mode selection circuit is used for controlling a working mode of the dual-switch Buck-Boost type DC-DC converter, the first capacitor is controlled to be discharged when the dual-switch Buck-Boost type DC-DC converter enters the working condition, a second capacitor is charged, a voltage loaded onto the first capacitor is maintained around an optimal value, and tracing of maximum powerpoint is achieved. The piezoelectric vibration energy collection system has the advantage of relatively high vibration energy collection efficiency.

The invention discloses a maximum power tracking control method for a photovoltaic system under partial shading. The method mainly comprises the steps of an initialization strategy, a constraint mechanism, fitness calculation, horizontal crisscross, vertical crisscross, global optimization saving and the like. A vertical and horizontal crisscross algorithm adopted by the method is a current novelintelligent optimization algorithm, and compared with particle swarm optimization (PSO), a genetic algorithm (GA) and other intelligent optimization algorithms, the vertical and horizontal crisscrossalgorithm achieves the high-dimensional non-convex multi-peak optimization purpose and has the advantages of high solution precision, high convergence speed and the like. The algorithm achieves the optimization iteration process of a population through the horizontal crisscross, the vertical crisscross and a competition operator, and finally the optimal solution is obtained.

The invention discloses a power control method of a wave power generation device based on Fourier analysis and an improved grey wolf algorithm. On the basis of reserving the most essential characteristic of a grey wolf optimization algorithm, a brand new elite wolf searching policy and a wolf pack integral unfolding policy are added, and an encirclement ring formingpolicy, a wolf pack prey searching mode and a wolf pack structure are optimized, so that the improved grey wolf algorithm can be prevented from falling into local optimum as a result of hydrodynamic force nonlinearity of a floater.A Fourier analysis method is introduced to decompose ocean incident waves and respond to moving parts of a motor, the corresponding optimum motor control parameters are solved for wave components within a floater capturing frequency range by means of the improved grey wolf algorithm, and the carried power is captured to the maximum extent, so that maximum power point tracing is achieved.

The invention provides a photovoltaic mini inverter. The inverter comprises a boost module and an inversion module; the boost module comprises a preceding DC-DC converter and a post DC-DC converter; and a photovoltaic array (PV), the preceding DC-DC converter, the post DC-DC converter and an the inversion module are connected in series successively. The preceding DC-DC converter uses a Sepic circuit to track the maximal power point and increase the voltage, the post DC-DC converter further increases the voltage to a power grid level, and the maximal power point is tracked while the boosting ratio is greater than 10. The characteristic of low switching loss of the circuit is utilized fully, high-frequency characteristic of a switched capacitor circuit is used, and the size and output ripple of a filter can be reduced effectively.

The invention discloses a power control method of a wave power generation device based on an improved bee colony algorithm. The method comprises the following steps of Step 1, solving the linear motorelectromagnetic force control parameters capable of changing the average output power of the wave power generation device; Step 2, improving the artificial bee colony algorithm by a criss-cross algorithm; and Step 3, applying the artificial bee colony algorithm improved through the step 2 to the maximum power point tracking control of the wave power generation device; and obtaining the optimal motor electromagnetic force control parameter of the wave power generation device under different wave frequencies, so that the average output power of the wave power generation device reaches the maximum value, and the maximum power point tracking is realized. The advantages of high convergence speed and high global searching capability of a CABC algorithm are utilized; the optimal linear motor electromagnetic force control parameters of the wave power generation device at different wave frequencies can be fast obtained; the condition that Rg, kc and kl trap in local optimum is avoided; the average output power of the wave power generation device reaches a possibly great value; and the maximum power point tracking is realized.

The invention discloses a high-energy-efficiency dual-input inverter suitable for a distributed photovoltaic grid-connected system, belonging to the technical field of power electronic converters. Theconverter consists of two DC input sources (VP - VN), two inverter arms (P - N), two integrated Boost circuits (Boost P - Boost N), two filter inductors (LP - LN), two low frequency switching transistors (SP - SN), a DC bus capacitor (CBus) and a power grid (vG). The control circuit of the inverter includes Boost- P, Boost- N, the inverter controller and PWM modulation unit. The invention can simultaneously realize the maximum power point tracking of two DC input sources VP and VN and the control of the output grid-connected current. The two inverter bridge arms of the present invention bothcontain diodes in reverse series, without the risk of the bridge arm going through. The invention generates a plurality of levels at the midpoint of the bridge arm, facilitating the reduction of switching losses and filter volumes. Only a small part of the energy of the invention needs to be processed by two Boost circuits, and most of the energy can be directly transferred to a power network by an inverter, thus reducing the number of power conversion stages, and the system efficiency is high.

The invention discloses a flyback grid-connected inverter with a low frequency ripple suppression function. The main circuit topology of the inverter includes an input DC power supply, an input capacitor, an input diode, an active decoupling circuit, an isolation transformer, a primary switching tube, a secondary diode, a secondary switching tube, an output filter circuit and a power grid. The output pulsating power is completely transferred to the decoupling capacitor by additionally arranging the active decoupling circuit on the basis of the traditional single-stage flyback grid-connected inverter structure so as to realize the suppression of the low frequency ripple of the input current and achieve the purpose of eliminating the high-capacity and short-life electrolytic capacitor.

The invention discloses a series photovoltaic optimization system and a control method thereof. The input end of each series photovoltaic optimizer is connected with the output of a corresponding photovoltaic panel in parallel, the output end of each series photovoltaic optimizer is connected with the output end of the corresponding photovoltaic panel in series, and the series photovoltaic optimizers enable each photovoltaic panel to realize the maximum power output through a mode of converting the unmatched energy from parallel connection into series connection, thereby effectively solving aproblem that the generating capacity of the system is reduced duo to the unmatched photovoltaic panels in a string. In addition, the series photovoltaic optimizers only convert the unmatched energy, so that the optimizers have the advantages of low power, low loss, small amount of generated heat and low cost.

Provided in the invention is a photovoltaic micro inverter comprising a boost module and an inversion module. The boost module consists of a pre-stage DC-DC converter and post-stage DC-DC converter. A photovoltaic array, the pre-stage DC-DC converter, the post-stage DC-DC converter, and the inversion module are connected in series. The pre-stage DC-DC converter includes an input capacitor C1, a boost circuit, and an output capacitor C2; the input capacitor C1 and the boost circuit are connected in parallel; and the boost circuit and the output capacitor C2 are connected in parallel. According to the invention, with full utilization of the circuit characteristic of low switch losses and the high-frequency characteristic of the switch capacitor circuit, the size and output ripple of the filter can be reduced effectively.

Disclosed is solar power-generation equipment which can have high available power by forming multilayer packages, each of which includes a power pump and a solar module. The solar power-generation equipment comprises: multiple solar module packages connected in series to each other and stacked in multiple layers; and at least one capacitor corresponding to each of the solar module packages. At least one of the solar module packages has: a solar module for supplying power to a load terminal; and a power pump for providing lifting power to the solar module. The solar module outputs power in which the lifting power provided from the power pump is reflected.