67results 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 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.

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 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.

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.

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 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.