SS型Buck-WPT(Buck-wireless power transfer)系统由Buck电路和基本的SS型无线电能传输电路组成。该电路系统因为结构和控制方式简单、控制效果明显等优点在感应式无线电能传输方面得到广泛应用。但该电路的动态特性并不能满足一些时变...SS型Buck-WPT(Buck-wireless power transfer)系统由Buck电路和基本的SS型无线电能传输电路组成。该电路系统因为结构和控制方式简单、控制效果明显等优点在感应式无线电能传输方面得到广泛应用。但该电路的动态特性并不能满足一些时变系统对快速性的较高要求。例如,系统在启动时会存在较强震荡和较大超调,系统负载改变时稳定状态会发生改变且存在明显抖动,系统极限空载时原边谐振电流会增大,且该电流值远超出安全工作范围。本文提出了一种基于可控电感的SS型Buck-WPT系统。首先,分析了电感值可调的方法并在COMSOL中建立仿真模型验证其电感值可控的特性。其次,对SS型Buck-WPT系统进行数学建模,将SS型WPT系统作为Buck电路的特殊负载,推导SS型Buck-WPT系统状态空间方程。研究其三维空间内相轨迹的降维描述方法,将该系统用二维相轨迹描述系统运行过程。然后,通过分析启动阶段相轨迹运行规律,改进前级Buck电路。将传统Buck电路中的电感换成可控电感,运用其电感值可调的控制系统开通阶段的运行轨迹,使系统在1个开关周期内无超调快速进入稳态。当系统负载改变时,系统的输出电压会改变,且是不断抖动来回反复的过程,利用PI算法对系统进行恒流控制。通过可控电感控制系统相轨迹,使副边输出能无抖动快速进入稳态,保证输出电压不变。针对SS型谐振网络的Buck-WPT系统中出现空载大电流的问题,提出了将可控电感串联接入原边谐振网络的方法。实时检测原边谐振电流值,该值超过正常工作范围,感值就快速增大,减小原边谐振电流,达到空载时维持原边谐振电流安全值以下。最后,验证上述方法在优化SS型Buck-WPT系统动态特性的有效性,在Simulink中搭建仿真电路。该方法能减小工作条件改变时带来的系统抖动,且在不改变系统响应速度前提下减小超调,优化系�展开更多
Linear induction motors are superior to rotary induction motors in direct drive systems because they can generate direct forward thrust force independent of mechanical transmission.However,due to the large air gap and...Linear induction motors are superior to rotary induction motors in direct drive systems because they can generate direct forward thrust force independent of mechanical transmission.However,due to the large air gap and cut-open magnetic circuit,their efficiency and power factor are quite low,which limit their application in high power drive systems.To attempt this challenge,this work presents a system-level optimization method for a single-sided linear induction motor drive system.Not only the motor but also the control system is included in the analysis.A system-level optimization method is employed to gain optimal steady-state and dynamic performances.To validate the effectiveness of the proposed optimization method,experimental results on a linear induction motor drive are presented and discussed.展开更多
The hysteresis control combined with PWM control non-inverting buck-boost was proposed to improve the light load efficiency and power density.The constant inductor current control(CICC)was established to mitigate the ...The hysteresis control combined with PWM control non-inverting buck-boost was proposed to improve the light load efficiency and power density.The constant inductor current control(CICC)was established to mitigate the dependence on the external components and device variation and make smooth transition between hysteresis control loop and pulse width modulation(PWM)control loop.The small signal model was deduced for the buck and boost operation mode.The inductor current slope control(ICSC)was proposed to implement the automatic mode transition between buck and boost mode in one switching cycle.The results show that the converter prototype has good dynamic response capability,achieving 94%efficiency and 95%peak efficiency at full 10 A load current.展开更多
An analog implementation of a novel fixed-frequency quasi-sliding-mode controller for single-inductor dual-output（SIDO） buck converter in pseudo-continuous conduction mode（PCCM） with a self-adaptive freewheeling c...An analog implementation of a novel fixed-frequency quasi-sliding-mode controller for single-inductor dual-output（SIDO） buck converter in pseudo-continuous conduction mode（PCCM） with a self-adaptive freewheeling current level（SFCL） is presented.Both small and large signal variations around the operation point are considered to achieve better transient response so as to reduce the cross-regulation of this SIDO buck converter.Moreover,an internal integral loop is added to suppress the steady-state regulation error introduced by conventional PWM-based sliding mode controllers.Instead of keeping it as a constant value,the free-wheeling current level varies according to the load condition to maintain high power efficiency and less cross-regulation at the same time.To verify the feasibility of the proposed controller,an SIDO buck converter with two regulated output voltages,1.8 V and 3.3 V,is designed and fabricated in HEJIAN 0.35 m CMOS process.Simulation and experiment results show that the transient time of this SIDO buck converter drops to 10 s while the cross-regulation is reduced to 0.057 mV/mA,when its first load changes from 50 to 100 mA.展开更多
文摘SS型Buck-WPT(Buck-wireless power transfer)系统由Buck电路和基本的SS型无线电能传输电路组成。该电路系统因为结构和控制方式简单、控制效果明显等优点在感应式无线电能传输方面得到广泛应用。但该电路的动态特性并不能满足一些时变系统对快速性的较高要求。例如,系统在启动时会存在较强震荡和较大超调,系统负载改变时稳定状态会发生改变且存在明显抖动,系统极限空载时原边谐振电流会增大,且该电流值远超出安全工作范围。本文提出了一种基于可控电感的SS型Buck-WPT系统。首先,分析了电感值可调的方法并在COMSOL中建立仿真模型验证其电感值可控的特性。其次,对SS型Buck-WPT系统进行数学建模,将SS型WPT系统作为Buck电路的特殊负载,推导SS型Buck-WPT系统状态空间方程。研究其三维空间内相轨迹的降维描述方法,将该系统用二维相轨迹描述系统运行过程。然后,通过分析启动阶段相轨迹运行规律,改进前级Buck电路。将传统Buck电路中的电感换成可控电感,运用其电感值可调的控制系统开通阶段的运行轨迹,使系统在1个开关周期内无超调快速进入稳态。当系统负载改变时,系统的输出电压会改变,且是不断抖动来回反复的过程,利用PI算法对系统进行恒流控制。通过可控电感控制系统相轨迹,使副边输出能无抖动快速进入稳态,保证输出电压不变。针对SS型谐振网络的Buck-WPT系统中出现空载大电流的问题,提出了将可控电感串联接入原边谐振网络的方法。实时检测原边谐振电流值,该值超过正常工作范围,感值就快速增大,减小原边谐振电流,达到空载时维持原边谐振电流安全值以下。最后,验证上述方法在优化SS型Buck-WPT系统动态特性的有效性,在Simulink中搭建仿真电路。该方法能减小工作条件改变时带来的系统抖动,且在不改变系统响应速度前提下减小超调,优化系�
文摘Linear induction motors are superior to rotary induction motors in direct drive systems because they can generate direct forward thrust force independent of mechanical transmission.However,due to the large air gap and cut-open magnetic circuit,their efficiency and power factor are quite low,which limit their application in high power drive systems.To attempt this challenge,this work presents a system-level optimization method for a single-sided linear induction motor drive system.Not only the motor but also the control system is included in the analysis.A system-level optimization method is employed to gain optimal steady-state and dynamic performances.To validate the effectiveness of the proposed optimization method,experimental results on a linear induction motor drive are presented and discussed.
文摘The hysteresis control combined with PWM control non-inverting buck-boost was proposed to improve the light load efficiency and power density.The constant inductor current control(CICC)was established to mitigate the dependence on the external components and device variation and make smooth transition between hysteresis control loop and pulse width modulation(PWM)control loop.The small signal model was deduced for the buck and boost operation mode.The inductor current slope control(ICSC)was proposed to implement the automatic mode transition between buck and boost mode in one switching cycle.The results show that the converter prototype has good dynamic response capability,achieving 94%efficiency and 95%peak efficiency at full 10 A load current.
基金Project supported by the National Natural Science Foundation of China (No.60906012)the Analog Devices,Inc.(ADI)
文摘An analog implementation of a novel fixed-frequency quasi-sliding-mode controller for single-inductor dual-output（SIDO） buck converter in pseudo-continuous conduction mode（PCCM） with a self-adaptive freewheeling current level（SFCL） is presented.Both small and large signal variations around the operation point are considered to achieve better transient response so as to reduce the cross-regulation of this SIDO buck converter.Moreover,an internal integral loop is added to suppress the steady-state regulation error introduced by conventional PWM-based sliding mode controllers.Instead of keeping it as a constant value,the free-wheeling current level varies according to the load condition to maintain high power efficiency and less cross-regulation at the same time.To verify the feasibility of the proposed controller,an SIDO buck converter with two regulated output voltages,1.8 V and 3.3 V,is designed and fabricated in HEJIAN 0.35 m CMOS process.Simulation and experiment results show that the transient time of this SIDO buck converter drops to 10 s while the cross-regulation is reduced to 0.057 mV/mA,when its first load changes from 50 to 100 mA.
