69results about "Proportional-integral algorithms" patented technology

A variable speed system for use in systems, such as, for example, wind turbines, is described. The system comprises a wound rotor induction generator, a torque controller and a proportional integral derivative (PID) pitch controller. The torque controller controls generator torque using field oriented control, and the PID controller performs pitch regulation based on generator rotor speed.

A variable speed wind turbine having a passive grid side rectifier using scalar power control and dependent pitch control is disclosed. The variable speed turbine may include an electrical generator to provide power for a power grid and a power conversion system coupled to the electrical generator. The power conversion system may include at least one passive grid side rectifier. The power conversion system may provide power to the electrical generator using the passive grid side rectifier. The variable speed wind turbine may also use scalar power control to provide more precise control of electrical quantities on the power grid. The variable speed wind turbine may further use dependent pitch control to improve responsiveness of the wind turbine.

A variable speed wind turbine having a passive grid side rectifier using scalar power control and dependent pitch control is disclosed. The variable speed turbine may include an electrical generator to provide power for a power grid and a power conversion system coupled to the electrical generator. The power conversion system may include at least one passive grid side rectifier. The power conversion system may provide power to the electrical generator using the passive grid side rectifier. The variable speed wind turbine may also use scaler power control to provide more precise control of electrical quantities on the power grid. The variable speed wind turbine may further use dependent pitch control to improve responsiveness of the wind turbine.

The present invention relates to a method and a system for operating a Wind Turbine (WTG), which WTG comprises a rotor comprising at least two blades, which blades are pitch regulated, where the rotor is connected to a shaft, which shaft is supported by bearings, and which shaft drives at least one generator, where the WTG uses a load regulation system for regulating the individual pitch of at least two blades. The object of the invention is to compensate for asymmetric load on the rotor in a wind turbine, a second object is to reduce wearing at shaft bearings in the wind turbine, and a third object is to increase the power production of a wind turbine. This can be achieved if the load regulation system measures the actual rotor load by at least one displacement sensor, which displacement sensor is measuring the bending of the main shaft, where the load regulation system based on the shaft bending regulates the individual pitch of the blades for compensating asymmetric load at the rotor.

A wind turbine includes a rotor having one or more rotor blades, a pitch system for controlling the pitch angle of the one or more rotor blades, the pitch system having at least one pitch actuator, a pitch controller for generating pitch actuator control signals and sensor elements for establishing values of pitch performance parameters, and a compensation controller to compensate for disparities between the pitch actuator control signals and the values of pitch performance parameters, according to a control algorithm. The compensation controller is arranged to adjust parameters of the control algorithm of the compensation controller in dependency of the disparities.

A rotational speed controlling device for a wind turbine is provided. The controlling device includes a first input node for receiving a first signal, indicative of an actual rotational speed of the rotor, a second input node for receiving a second signal, indicative of a reference rotational speed for the rotor, a detection unit for detecting a defective operational state in which the wind turbine is impeded to export electrical power to an electricity network, a control unit for providing a reference signal for a characteristic operational parameter of the wind turbine based on the first signal and the second signal, and a pulse generator adapted to send a kick pulse to an integral control element of the control unit in response to the detection of the defective operational state. The characteristic operational parameter is indicative of the rotational speed of the rotor.

The invention provides a whole plant water turbine speed regulation systems health state evaluation and optimization method. The whole plant water turbine speed regulation systems intelligent analysisplatform obtains characteristic parameters of all parts of the whole plant water turbine speed regulation systems through an industrial ethernet, the characteristic parameters of same components of different water turbine speed regulation systems in the whole plant are compared and calculated, a health state indexes of all the components of each set of water turbine speed regulation system are corrected, so that the health state of each set of water turbine speed regulation system can be evaluated more accurately and timely. The whole plant water turbine speed regulation systems intelligent analysis platform obtains information of water heads, active power, guide vane opening degrees and a vibration swing degree of whole plant water turbine generator sets through the industrial ethernet,a comprehensive characteristic curve of the water head, the active power, the guide vane opening degree and a electric operation limit of each water turbine generator set are founded through long-timeoperation data accumulation and analysis, and an ultra-limiting region of the vibration swing degree is identified, so as to optimize a power regulation and primary frequency modulation of the waterturbine speed regulation systems, thus the overload of the sets is avoided, meanwhile, the ultra-limiting region of the vibration swing degree is avoided.

A control method and a wind turbine for adaptively adjusting the operation of the wind turbine to maintain maximum power production during degraded conditions. The control system has an estimator module that determines a scaling factor based on the current set of control signals and at least the current set of measurement of the operating parameters. The scaling factor is transmitted to a control module which scales at least one aerodynamic property of the rotor based on this scaling factor. The control module further determines the ideal settings for the control signals based on the scaled aerodynamic properties. The present control method scales the aerodynamic properties to provide a better representation of the actual degraded aerodynamic properties.

A method for controlling load reduction for a wind turbine rotor with rotor blades comprising an aerodynamic active element responsive to a control signal for modifying its setting is provided. The loads acting on the rotor blades in relation to the rotor's azimuth are detected and individual control signals based on a PI control system are established. Each individual control signal is a complex number containing an amplitude defining the degree of modification of the respective setting and an angle defining the phase of the modification of the respective setting with respect to the rotor's azimuth. The angle of the complex number is corrected by a phase correction factor. The elements are provided with the individual control signals. The input to the PI-control system is a complex load vector.

The present invention relates to a control system for thrust-limiting of wind turbines, which wind turbine comprises at least one tower, which tower carries at least one nacelle which nacelle comprises a rotating shaft, which shaft is rotated by one or more blades, which blades at pitch regulated by a pitch control system. It is the object of the present invention to reduce mechanical load and stress of a wind turbine. A further object is to reduce the maximal load on tower of a wind turbine. The thrust-limiting control system performs control of the pitch angle, which thrust-limiting control system performs regulation of the pitch angle based on at least a first input from a wind estimator and a second input from a turbulence estimator. By thrust-limiting control, reduction in the maximum mechanical load on a tower, or maybe also a nacelle, can be achieved by a relatively high percentage of the load in a way where it has only very limited influence on the power production of the wind turbine.

The invention relates to a wind turbine comprising a rotor including one or more rotor blades, a pitch system for controlling the pitch angle of said one or more rotor blades, said pitch system comprises at least one pitch actuator, a pitch controller for generating pitch actuator control signals and sensor elements for establishing values of pitch performance parameters, and a compensation controller to compensate for disparities between said pitch actuator control signals and said values of pitch performance parameters, according to a control algorithm. The the compensation controller is arranged to adjust parameters of the control algorithm of said compensation controller in dependency of said disparities. Furthermore the invention relates to a method for compensating for disparities in a wind turbine rotor blade pitch system and use of a method.

The invention discloses a variable-pitch control method based on fuzzy feedforward and fuzzy-PI. The variable-pitch control method comprises fuzzy feedforward control and fuzzy-PI control. A proper feedforward compensation angle is provided according to the interference of the fuzzy feedforward control with the wind speed, and the feedforward compensation angle pluses an output pitch angle of the fuzzy-PI control to serve as the reference value of the pitch angle; and according to the fuzzy-PI control, the fuzzy-PI control is double-mode control composed of the fuzzy control and the PI control; and when the power change range is large, the fuzzy control is adopted, and when the power change range is small, the PI control is smoothly switched to through a nonlinear function. By the adoption of the variable-pitch control method based on the fuzzy feedforward and the fuzzy-PI, the problem that only PID control is used in a strong-nonlinearity wind power system and consequently the satisfactory control effect cannot be achieved is solved, the design difficulty of a controller is lowered, the dynamic-static feature of the system is improved, the output power of an electric generator can be quickly stabilized to be near the rated value, and the impact of wind-power integration on a grid is reduced.

The invention discloses a wind power generation maximum output power tracking method and system based on rotation speed control. The method comprises the steps that a power given value is obtained according to the current rotation speed and the reference rotation speed; the feedforward power is determined according to the current rotation speed; the power given value is added to the feedforward power to obtain the power given value before amplitude limiting, and dynamic amplitude limiting is conducted to obtain the power given value after amplitude limiting; the output power of a wind driven generator is subtracted from the power given value after amplitude limiting, and a current given value is obtained through PI control; and the output current of the wind driven generator is subtracted from the current given value, and a control signal used for controlling the wind driven generator to generate power is obtained through PI control. The system comprises a rotation speed outer loop unit, a feedforward power searching unit, a power given unit, a power given amplitude limiting unit, a power inner loop unit and a current inner loop unit. By the adoption of the wind power generation maximum output power tracking method and system, the sensibility of external parameters containing wind speed measurement and a maximum power curve can be tracked with the maximum power, and the maximum power point can be tracked rapidly and accurately.

A method for operating a wind turbine and / or a wind farm for feeding electric power into an electrical supply grid, wherein an output power, in particular an active and / or reactive power, is regulated by means of at least one power regulation module of a regulation and / or control device, said method comprising the following steps: presetting a power regulation input value, determining a power regulation output value from the power regulation input value, and outputting a power regulation output value.In accordance with the present embodiments, provision is made for the power regulation module to have a P regulator and an I regulator and to have an I-component limiter, wherein a first working value of the power regulation input value is processed in the P regulator to give a P component, a second working value of the power regulation input value is processed in the I regulator to give an I component, and a third working value of the power regulation input value is processed in the I-component limiter to give a limited I component, and the power regulation output value with the limited I component and the P component is determined.

Aiming at the variable propeller pitch control problem of a wind power generation system, the invention provides a variable propeller pitch control method based on proportion-extreme learning machinesteady state estimation. According to the variable propeller pitch control method based on the proportion-extreme learning machine steady state estimation, firstly, steady-state output of a PI controller of a wind generation set under various wind speeds is leaned through an ELM, and then variable propeller control of the wind generation set is performed adopting a method of combining the trainedELM and a proportional controller. By means of the variable propeller pitch control method based on the proportion-extreme learning machine steady state estimation, the defect of lag of traditional PIvariable propeller pitch control can be improved, and the stability of the output power of the wind generation set is facilitated.

The invention discloses a rotating speed control method for ensuring stability of inertia response control of a large wind generation set. The rotating speed control method comprises the following steps that (1) the power grid frequency is detected by a wind generation set converter; (2) a wind generation set main control system controls a dead zone according to the power grid frequency and inertia response and judges whether the wind generation set enters into an inertia response control mode or not; (3) if yes, the wind generation set simulates the inertia response effect by releasing rotational kinetic energy stored by a wind generation set impeller and a power generator; (4) when the situation that the power grid frequency is restored within a dead zone range is judged or the situationthat the wind generation set is in the critical ability of inertia support is judged by the wind generation set, the rotating speed of the wind generation set begins to restore, and a constant rotating speed restoring control method is adopted; and (5) when the situation that the wind generation set is restored to the state that the output power is within the range of 90%-110% of the theoreticalpower of variable speed and variable pitch control operation is judged, the wind generation set enters into a switching control mode with a smooth and continuous accelerated speed. The rotating speedcontrol method for ensuring the stability of inertia response control of the large wind generation set solves the problems of secondary impact of a power grid and shutdown of the wind generation set due to the unsteady rotating speed of the wind generation set.

The invention discloses a power limiting control method for a variable speed constant frequency wind turbine generator and capable of reducing the variable pitch frequency. According to the method, a rotation speed critical decrease variable is introduced into a variable pitch controller, characteristics of a wind turbine are fully utilized, the unbalanced power is adjusted through kinetic energy of a wind wheel preferably, the action mechanism of a variable pitch system is optimized, and the problem that a variable pitch mechanism acts frequently in the high-air-speed stage is effectively solved. According to the method, by changing the decrease action value of the variable pitch system, the unbalanced kinetic energy is released or absorbed through the wind wheel of the wind turbine preferably, the action frequency and action amplitude of the variable pitch system can be effectively reduced on the premise that the target power output of the wind turbine is met, and accordingly the mechanical fatigue of the variable pitch system is relieved, and the service life of the variable pitch system is prolonged.

The present invention relates to a method for controlling a wind turbine, the wind turbine comprises a rotor connected to a generator, and a rotational speed controller configured to control a speed of the rotor in response to a generator speed reference, and a power controller to control an electric power production, the method comprises the step for receiving a boost command to request a power boost event, so to increase the electrical power production, and imposing a dead band with a dead zone value limit to the rotational speed controller, and wherein the dead band imposes a zero signal to be send to the rotational speed controller, when a speed error is within the dead zone value limit and wherein the dead band imposes an error signal to be send to the rotational speed controller, when a speed error is greater than the dead zone value limit, the error signal being a function of the speed error and the dead zone value limit. The invention also relates to a wind power plant comprising a power plant controller and at least one wind turbine with a control system according to the above mentioned method.

The invention provides a fan variable pitch control method and system based on a PI algorithm. The fan variable pitch control method comprises the steps that a shear wind speed is filtered out by feedforward control, and a wind speed measurement error is supplemented; wind speed change is input into a variable pitch controller as an interference value, and a difference value between collected real-time power of a generator and rated power of the generator is sent to the variable pitch controller; the variable pitch controller of a fan adopts the PI algorithm, a pitch angle can be quickly and accurately adjusted when the wind speed changes frequently and disturbance of fan blades is large, so that the fan blades are prevented from shaking due to uneven stress, the fan can be maintained in the rated generator power state, and the steady and dynamic performance of a fan variable pitch system can be effectively controlled. The response time of the fan variable pitch control system is shortened, the rapidity of the system is improved, the output power of a fan unit is stabilized, and the power generation efficiency of the fan unit is improved.

The invention provides a gas flow control method and device of dual-fuel engine. The method comprises the following steps: acquiring current revolving speed information and current power information of the engine and current open degree of a gas flow control valve; inquiring required open degree of the gas flow control valve in an MAP chart according to the current revolving speed information and the current power information; controlling through proportional integral according to the current open degree and the required open degree, and outputting a driving control signal so as to control the engine to run under the required open degree of the gas flow control valve, wherein the MAP chart is a relation chart of the revolving speed of the engine and the required open degree of the gas flow control valve. The method can effectively improve emission level of the engine on the premise of relatively low modification, application and maintenance costs.

A rotational speed controlling device for a wind turbine is provided. The controlling device includes a first input node for receiving a first signal, indicative of an actual rotational speed of the rotor, a second input node for receiving a second signal, indicative of a reference rotational speed for the rotor, a detection unit for detecting a defective operational state in which the wind turbine is impeded to export electrical power to an electricity network, a control unit for providing a reference signal for a characteristic operational parameter of the wind turbine based on the first signal and the second signal, and a pulse generator adapted to send a kick pulse to an integral control element of the control unit in response to the detection of the defective operational state. The characteristic operational parameter is indicative of the rotational speed of the rotor.

The present invention is a method for controlling a wave-energy-converter system, wherein the gains of a control law having a proportional component are optimally determined in terms of the harvest of energy, and are robust with respect to uncertainties in the dynamics of the wave-energy-converter system. The harvest of energy is maximized for the worst case described by the uncertainties, by solving a semidefinite-positive optimization problem.