【作者】 张东升；

【导师】 苏宝库；

【作者基本信息】 哈尔滨工业大学 ， 控制科学与工程， 2009， 博士

【摘要】 电力电子装置的广泛应用在给电能的变换及应用带来方便的同时,也给电力系统带来了严重的谐波和无功污染。为此,研究具有高功率因数和低输入电流畸变率(Total Harmonic Distortion, THD)的绿色无污染的PWM整流装置已成为电力电子应用技术中的一个重大研究课题。VIENNA整流器(三相三电平三开关boost整流器)具有功率因数高,输入电流THD低,开关器件少,开关应力低,可靠性高等特征,对该整流器控制问题的研究具有重要的理论意义和工程价值。首先,针对VIENNA整流器,提出了一种改进PODRCC方法。该调制方法引入了负载反馈机制,有效解决了轻载和空载输出电压不可控的问题。利用状态空间法,给出了VIENNA整流器在abc静止坐标系、αβ两相静止坐标系和dq两相旋转坐标系下的数学模型。通过对同相双载波补偿控制(PDDRCC)和反相双载波补偿控制(PODRCC)两种方法进行分析,得出PODRCC方法更易于实现且可靠性高。上述内容为后续研究奠定了基础。其次,提出了一种基于改进型ANF的三相EPLL控制策略,并用BF-PSO算法对控制器参数进行优化设计。BF-PSO算法将粒子群优化(PSO)算法作为一个变异算子引入细菌觅食(BF)优化算法,以此提高优化算法的搜索能力、搜索精度和搜索速度。在此基础上,提出了一种基于BF-PSO优化的改进型自适应陷波滤波器(ANF),解决了较大扰动和噪声情况下获取单相系统同步电压信息问题,并利用均值理论对其稳定性进行了分析。针对传统的三相锁相环(PLL)难以处理输入电压不平衡问题,提出了基于改进型自ANF的三相增强型锁相环(EPLL),对输入电压畸变条件下的EPLL非线性模型进行了推导,并用Lyapunov第二法对该模型稳定性和跟踪能力进行分析。然后,提出了基于模糊比例谐振(FLPR)控制的电流解耦控制算法,提高VIENNA整流器输入电流的跟踪特性。对VIENNA整流器的电流解耦控制方法进行分析,得出在αβ坐标系下可实现VIENNA整流器电流控制的解耦。将基于内模原理的比例谐振控制算法应用到电流跟踪控制环节中,实现了VIENNA整流器的电流无误差跟踪控制。为了增强控制系统的鲁棒性和抗干扰能力,设计了一个模糊调整器,可根据系统误差实时地调整比例谐振控制器参数,以取得良好的稳态精度与动态响应速度。再次,提出基于BF-PSO的分数阶控制器,提高了VIENNA整流器直流电压控制精度。将BF-PSO算法引入到控制器参数的求解当中,解决了分数阶控制器参数难以设计问题。然后将所提方法应用到VIENNA整流器直流母线电压控制中,提高了控制精度,并增强了系统的稳定性。同时,针对三电平变换器固有的电容中点电压波动问题,设计了基于BF-PSO算法的限幅比例因子的中点电压控制器,实现了中点电压的高精度平衡调节,并减少了中点平衡调节对电流THD的影响。最后,根据VIENNA整流器的性能指标和功能要求,给出了系统的总体设计方案,搭建了基于DSP 2812的控制平台和功率单元。在此基础上,应用前文所提方法设计了VIENNA整流器电压外环、电流内环以及中点平衡的控制器,并加以实现。系统实验结果表明,各项指标达到了设计要求,验证了所提控制策略的可行性和有效性。更多还原

【Abstract】 Prevailing of power electronics brings convenience to energy conversion and utilization on one hand and also causes harmonics and reactive power problems on the other hand. Therefore the study on green and clean PWM rectifier with high power factor and low input current distortion has become an important issue for the technology of power electronics application. VIENNA rectifier, i.e. three-level three-switch boost rectifier is prevailing due to its merits such as high power factor , low Total Harmonic Distortion (THD) of input current, few switch devices, low switch stress and high reliability. And research on the controlling of VIENNA rectifier has important theory significance and engineering merit.First, an improved Disposition Opposition Double Ramp Comparison Control (PDDRCC) method is proposed for the control of VIENNA rectifier. This modulation method effectively solves the problem of output voltage is not controllable with light load and no-load by the introduction of feedback mechanism to it. With state space method mathematic models of the rectifier are established on static coordinate system, two-phase static coordinate system and two-phase rotating coordinate system respectively. Analysis of Phase Disposition Double Ramp Comparison Control (PDDRCC) and PODRCC methods show that PODRCC method is easier to achieve and attains higher reliability. This is the foundation of the following researches.Second, an Enhanced Phase Locked Loop (EPLL) control strategy based on improved Adaptive Notch Filtering (ANF) is proposed, controller parameters are optimized using BF-PSO algorithm. In this method, particle swarm optimization (PSO) algorithm is introduced to Bacterial Foraging (BF) optimization algorithm as a mutation operator to enhance the global searching ability of optimization algorithm, obtaining a new BF-PSO hybrid optimization algorithm. On this basis, an improved adaptive notch filter based on BF-PSO hybrid optimization algorithm is given to solve the problem of obtaining synchronization voltage information of single-phase system under larger disturbances and noise. Then the stability of the improved adaptive notch filter is analyzed according to mean theory. Aiming at the input voltage imbalance of traditional three-phase PLL, three-phase EPLL is proposed based on improved ANF. The nonlinear model of EPLL is deduced under the condition of input voltage distortion. Then the stability and tracking ability of the model is analyzed according to Lyapunov’s second method.Third, a current decoupling method is proposed based on Fuzzy Logic Proportional Resonant (FLPR), which can improve the tracking characteristics of the input current of VIENNA rectifier. Through the analysis of the current decoupling control method of VIENNA rectifier, it can be obtained that the current control of the rectifier can be decoupled successfully on two-phase static coordinate system. A proportional resonant controller based on internal model theory is used in current tracking control of the rectifier, by which the zero error tracking control of the VIENNA rectifier is realized. In order to improve the robustness and anti-interference ability of the control system a fuzzy regulator is designed, which regulates the parameters of the generalized integral controller real-timely according to system error, and validates the proposed method through simulation.Four, fractional order controller is proposed based on BF-PSO algorithm to improve the DC voltage control precision of VIENNA rectifier. The BF-PSO algorithm is introduced to solve the problem of parameters design fractional order controller. Furthermore, the method is used to control the DC bus voltage of the VIENNA rectifier, with enhanced control accuracy and system stability. Moreover, aiming at the inherent problem of capacitor neutral-point voltage fluctuation in three-phase converters, a neutral-point potential controller is designed based on BF-PSO amplitude limit factor, which can attain the balance adjustment of the neutral-point potential with high precision and reduce the effect of the adjustment on current THD.At last, a general design scheme is given according to the performance index and functional requirements of VIENNA rectifier. The power unit and control configuration based on DSP2812 is established. Based on this, outer voltage loop, internal current loop and balancing neutral-point potential controller is designed according to the proposed methods and realized. Experimental results show that the performance indexes meet the design requirements and the proposed control strategy is viable and efficiency.更多还原