In order to improve the steady state performance,dynamic response and power factor of traditional power factor correction(PFC)digital control method and reduce the harmonic distortion of input current,a double closed ...In order to improve the steady state performance,dynamic response and power factor of traditional power factor correction(PFC)digital control method and reduce the harmonic distortion of input current,a double closed loop active power factorcorrection(APFC)control method with feed-forward is proposed.Firstly,the small signal model of Boost PFC control systemis built and the system transfer function is deduced,and then the parameters of the main device with Boost topology is estimated.By means of the feed-forward,the system can quickly respond to the change in input voltage.Furthermore,the use ofvoltage loop and current loop can achieve input current and output voltage regulation Simulink modeling shows that this methodcan effectively control the output voltage in case of input voltage largely fluctuating,improve the system dynamic response abilityand input power factor,and reduce the input current harmonic distortion展开更多
Dual-point composition control for a high-purity ideal heat integrated distillation column (HIDiC) is addressed in this work. Three measures are suggested and combined for overcoming process inherent nonlinearities:(1...Dual-point composition control for a high-purity ideal heat integrated distillation column (HIDiC) is addressed in this work. Three measures are suggested and combined for overcoming process inherent nonlinearities:(1) variable scaling; (2) multi-model representation of process dynamics and (3) feedforward compensation. These strategies can offer the developed control systems with several distinct advantages: (1) capability of dealing with severe disturbances; (2) tight tuning of controller parameters and (3) high robustness with respect to variation of operating conditions. Simulation results demonstrate the effectiveness of the proposed methodology.展开更多
The objective of this study is the simulation of the fuzzy control of a double-fed induction wind generator (DFIG) and oriented stator flux using MATLAB/S[MULINK. The system consists of a horizontal wind turbine, co...The objective of this study is the simulation of the fuzzy control of a double-fed induction wind generator (DFIG) and oriented stator flux using MATLAB/S[MULINK. The system consists of a horizontal wind turbine, coupled to a DFIG and driven by a feed consisting of two three+phase PWM converters in double bridge in order to maximize the delivered power at different wind speeds. We used a traditional regulator and a fuzzy controller. A model of the wind speed and the wind turbine is presented followed by the modeling of double-fed asynchronous generator DFIG controlled by fuzzy logic is performed according to two scenarios: with and without MPPT.展开更多
This paper presents the control ofa WECS (wind energy conversion system), equipped with a DFIG (doubly fed induction generator), for maximum power generation and power quality improvement simultaneously. The propo...This paper presents the control ofa WECS (wind energy conversion system), equipped with a DFIG (doubly fed induction generator), for maximum power generation and power quality improvement simultaneously. The proposed control algorithm is applied to a DFIG whose stator is directly connected to the grid and the rotor is connected to the grid through a back-to-back AC-DC-AC PWM (pulse width modulation) converter. The RSC (rotor side converter) is controlled in such a way to extract a maximum power, for a wide range of wind speed. The GSC (grid side converter) is controlled in order to filter harmonic currents of a nonlinear load coupled at the PCC (point of common coupling) and ensure smooth DC bus voltage. Simulation results show that the wind turbine can operate at its optimum energy for a wide range of wind speed and power quality improvement is achieved.展开更多
The power of the toroidal field (TF) coil in HL-2A is supplied with two 80 MVA motor generators (MGs) together through a diode rectifier. The TF system is designed to obtain the parameters as follows: the highest...The power of the toroidal field (TF) coil in HL-2A is supplied with two 80 MVA motor generators (MGs) together through a diode rectifier. The TF system is designed to obtain the parameters as follows: the highest toroidal filed of 2.8 T, the biggest coil current of 45 kA, the fiat top time of 3-5 s. So the released energy of each MG set for one pulse discharge mast be more than 500 MJ.展开更多
In this work, the authors propose the study of a wind speed variable based on the DFAM (double fed asynchronous machine). The model of the turbine is drawn from the classical equations describing the operation of a ...In this work, the authors propose the study of a wind speed variable based on the DFAM (double fed asynchronous machine). The model of the turbine is drawn from the classical equations describing the operation of a variable wind speed. The torque generated by the turbine is applied to the DFAM directly connected on the network side and the stator via a bidirectional converter side rotor. This configuration allows velocity variations of ±30% around the synchronous speed and the converter is then sized to one third of the rated power of the machine. The DFAM is controlled by a control vector ensuring operation of the wind turbine power coefficient maximum.展开更多
基金National Natural Science Foundation of China(No.61261029)
文摘In order to improve the steady state performance,dynamic response and power factor of traditional power factor correction(PFC)digital control method and reduce the harmonic distortion of input current,a double closed loop active power factorcorrection(APFC)control method with feed-forward is proposed.Firstly,the small signal model of Boost PFC control systemis built and the system transfer function is deduced,and then the parameters of the main device with Boost topology is estimated.By means of the feed-forward,the system can quickly respond to the change in input voltage.Furthermore,the use ofvoltage loop and current loop can achieve input current and output voltage regulation Simulink modeling shows that this methodcan effectively control the output voltage in case of input voltage largely fluctuating,improve the system dynamic response abilityand input power factor,and reduce the input current harmonic distortion
基金Supported by the New-Energy and Industry Technology Development Organization (NEDO) through the Energy Conservation Center of Japan.
文摘Dual-point composition control for a high-purity ideal heat integrated distillation column (HIDiC) is addressed in this work. Three measures are suggested and combined for overcoming process inherent nonlinearities:(1) variable scaling; (2) multi-model representation of process dynamics and (3) feedforward compensation. These strategies can offer the developed control systems with several distinct advantages: (1) capability of dealing with severe disturbances; (2) tight tuning of controller parameters and (3) high robustness with respect to variation of operating conditions. Simulation results demonstrate the effectiveness of the proposed methodology.
文摘The objective of this study is the simulation of the fuzzy control of a double-fed induction wind generator (DFIG) and oriented stator flux using MATLAB/S[MULINK. The system consists of a horizontal wind turbine, coupled to a DFIG and driven by a feed consisting of two three+phase PWM converters in double bridge in order to maximize the delivered power at different wind speeds. We used a traditional regulator and a fuzzy controller. A model of the wind speed and the wind turbine is presented followed by the modeling of double-fed asynchronous generator DFIG controlled by fuzzy logic is performed according to two scenarios: with and without MPPT.
文摘This paper presents the control ofa WECS (wind energy conversion system), equipped with a DFIG (doubly fed induction generator), for maximum power generation and power quality improvement simultaneously. The proposed control algorithm is applied to a DFIG whose stator is directly connected to the grid and the rotor is connected to the grid through a back-to-back AC-DC-AC PWM (pulse width modulation) converter. The RSC (rotor side converter) is controlled in such a way to extract a maximum power, for a wide range of wind speed. The GSC (grid side converter) is controlled in order to filter harmonic currents of a nonlinear load coupled at the PCC (point of common coupling) and ensure smooth DC bus voltage. Simulation results show that the wind turbine can operate at its optimum energy for a wide range of wind speed and power quality improvement is achieved.
文摘The power of the toroidal field (TF) coil in HL-2A is supplied with two 80 MVA motor generators (MGs) together through a diode rectifier. The TF system is designed to obtain the parameters as follows: the highest toroidal filed of 2.8 T, the biggest coil current of 45 kA, the fiat top time of 3-5 s. So the released energy of each MG set for one pulse discharge mast be more than 500 MJ.
文摘In this work, the authors propose the study of a wind speed variable based on the DFAM (double fed asynchronous machine). The model of the turbine is drawn from the classical equations describing the operation of a variable wind speed. The torque generated by the turbine is applied to the DFAM directly connected on the network side and the stator via a bidirectional converter side rotor. This configuration allows velocity variations of ±30% around the synchronous speed and the converter is then sized to one third of the rated power of the machine. The DFAM is controlled by a control vector ensuring operation of the wind turbine power coefficient maximum.