The giant magnetostrictive rotary ultrasonic processing system(GMUPS)with a loosely-coupled contactless power transfer(LCCPT)has emerged as a high-performance technique for the processing of hard and brittle materials...The giant magnetostrictive rotary ultrasonic processing system(GMUPS)with a loosely-coupled contactless power transfer(LCCPT)has emerged as a high-performance technique for the processing of hard and brittle materials,owing to its high power density.A capacitive compensation is required to achieve the highest energy efficiency of GMUPS to provide sufficient vibration amplitude when it works in the resonance state.In this study,an accurate model of the optimal compensation capacitance is derived from a new electromechanical equivalent circuit model of the GMUPS with LCCPT,which consists of an equivalent mechanical circuit and an electrical circuit.The phase lag angle between the mechanical and electrical circuits is established,taking into account the non-negligible loss in energy conversion of giant magnetostrictive material at ultrasonic frequency.The change of system impedance characteristics and the effectiveness of the system compensation method under load are analyzed.Both idle vibration experiments and machining tests are conducted to verify the developed model.The results show that the GMUPS with optimal compensation capacitance can achieve the maximum idle vibration amplitude and smallest cutting force.In addition,the effects of magnetic conductive material and driving voltages on the phase lag angle are also evaluated.展开更多
This paper presents a modelling and parameter identification of through-hole type contactless slipring systems for transferring electrical power for wind turbine pitch control. An equivalent circuit model has been dev...This paper presents a modelling and parameter identification of through-hole type contactless slipring systems for transferring electrical power for wind turbine pitch control. An equivalent circuit model has been developed from the physical structure and dimensions of the contactless slipring using the duality rules, which is very different form traditional transformer. The circuit inductances are determined by the derived expressions from the system reluctances. In particular, the equivalent resistance representing the core loss of the slipring has been determined using phasor diagram of exciting current. FEM (Finite Element Method) models and practical prototypes are developed for testing and verifycations. Both simulation and experimental results have shown that the developed model gives truthful values for numerical calculations in order to obtain the equivalent electric circuit. The effect of fringing flux around the air gap on mutual inductance and the ways of correcting its effects are analysed. The obtained values have shown that the developed models and derived equations are with high accuracy as compared to the FEM simulation and experimental results.展开更多
针对多负载移动式非接触感应电能传输(inductive contactless power transfer,ICPT)系统的设计与控制进行研究,分析LCL电路的输出特性和阻抗特性,当其电感之比等于1时,其谐振频率与负载无关,满足多负载ICPT的要求;介绍多负载移动式ICPT...针对多负载移动式非接触感应电能传输(inductive contactless power transfer,ICPT)系统的设计与控制进行研究,分析LCL电路的输出特性和阻抗特性,当其电感之比等于1时,其谐振频率与负载无关,满足多负载ICPT的要求;介绍多负载移动式ICPT系统的结构,并建立其等效电路模型,通过对等效模型的分析,提出原副边独立控制的控制策略和补偿电路设计原则,补偿电路要能够实现谐振频率与负载无关,以实现负载可变;分析LCL补偿电路的设计方法,分析副边LCL补偿和串联补偿的区别,当副边品质因数小于1时,LCL补偿输出功率更大;建立多负载移动式ICPT系统的仿真和实验平台,对理论分析和设计方法进行验证。展开更多
基金supported by the National Natural Science Foundation of China(Nos.51875311 and 52105458)the Tsinghua-Foshan Innovation Special Fund(No.2021THFS0204)the Huaneng Group Science and Technology Research Project(No.HNKJ22-U22YYJC08),China。
文摘The giant magnetostrictive rotary ultrasonic processing system(GMUPS)with a loosely-coupled contactless power transfer(LCCPT)has emerged as a high-performance technique for the processing of hard and brittle materials,owing to its high power density.A capacitive compensation is required to achieve the highest energy efficiency of GMUPS to provide sufficient vibration amplitude when it works in the resonance state.In this study,an accurate model of the optimal compensation capacitance is derived from a new electromechanical equivalent circuit model of the GMUPS with LCCPT,which consists of an equivalent mechanical circuit and an electrical circuit.The phase lag angle between the mechanical and electrical circuits is established,taking into account the non-negligible loss in energy conversion of giant magnetostrictive material at ultrasonic frequency.The change of system impedance characteristics and the effectiveness of the system compensation method under load are analyzed.Both idle vibration experiments and machining tests are conducted to verify the developed model.The results show that the GMUPS with optimal compensation capacitance can achieve the maximum idle vibration amplitude and smallest cutting force.In addition,the effects of magnetic conductive material and driving voltages on the phase lag angle are also evaluated.
文摘This paper presents a modelling and parameter identification of through-hole type contactless slipring systems for transferring electrical power for wind turbine pitch control. An equivalent circuit model has been developed from the physical structure and dimensions of the contactless slipring using the duality rules, which is very different form traditional transformer. The circuit inductances are determined by the derived expressions from the system reluctances. In particular, the equivalent resistance representing the core loss of the slipring has been determined using phasor diagram of exciting current. FEM (Finite Element Method) models and practical prototypes are developed for testing and verifycations. Both simulation and experimental results have shown that the developed model gives truthful values for numerical calculations in order to obtain the equivalent electric circuit. The effect of fringing flux around the air gap on mutual inductance and the ways of correcting its effects are analysed. The obtained values have shown that the developed models and derived equations are with high accuracy as compared to the FEM simulation and experimental results.
文摘针对多负载移动式非接触感应电能传输(inductive contactless power transfer,ICPT)系统的设计与控制进行研究,分析LCL电路的输出特性和阻抗特性,当其电感之比等于1时,其谐振频率与负载无关,满足多负载ICPT的要求;介绍多负载移动式ICPT系统的结构,并建立其等效电路模型,通过对等效模型的分析,提出原副边独立控制的控制策略和补偿电路设计原则,补偿电路要能够实现谐振频率与负载无关,以实现负载可变;分析LCL补偿电路的设计方法,分析副边LCL补偿和串联补偿的区别,当副边品质因数小于1时,LCL补偿输出功率更大;建立多负载移动式ICPT系统的仿真和实验平台,对理论分析和设计方法进行验证。
