针对当前新的42V汽车供电系统发展的必然趋势,提出一种基于42V Power Net的车用双向AC-DC矩阵式变换器,代替了传统的PWM整流电路和DC-DC变换器。在新提出的结构中,不再需要大的直流母线电容。三相交流电通过矩阵式变换器的一级变换就可...针对当前新的42V汽车供电系统发展的必然趋势,提出一种基于42V Power Net的车用双向AC-DC矩阵式变换器,代替了传统的PWM整流电路和DC-DC变换器。在新提出的结构中,不再需要大的直流母线电容。三相交流电通过矩阵式变换器的一级变换就可以得到期望输出的42V直流电,能量传输密度比传统整流电路高。本文采用基于间接空间矢量调制的闭环控制策略,表明了其有效性,确保了输出电压的可调节性和在不同负载下高质量的输入电流。展开更多
Fast response and stable torque output are crucial to the performance of electric screw presses. This paper describes the design of a direct torque control (DTC) system for speeding up torque response and reducing the...Fast response and stable torque output are crucial to the performance of electric screw presses. This paper describes the design of a direct torque control (DTC) system for speeding up torque response and reducing the starting current of electric screw presses and its application to the J58K series of numerical control electric screw presses with a dual-motor drive. The DTC drive system encompasses speed control, torque reference control, and switching frequency control. Comparison of the DTC dual-AC induction motor drive with corresponding AC servo motor drive showed that for the J58K-315 electric screw press, the DTC drive system attains a higher maximum speed (786 r/min) within a shorter time (1.13 s) during a 250 mm stroke and undergoes smaller rise in temperature (42.0 °C) in the motor after running for 2 h at a 12 min-1 strike frequency than the AC servo motor drive does (751 r/min within 1.19 s, and 50.6 °C rise). Moreover, the DTC AC induction motor drive, with no need for a tachometer or position encoder to feed back the speed or position of the motor shaft, enjoys increased reliability in a strong-shock work environment.展开更多
文摘针对当前新的42V汽车供电系统发展的必然趋势,提出一种基于42V Power Net的车用双向AC-DC矩阵式变换器,代替了传统的PWM整流电路和DC-DC变换器。在新提出的结构中,不再需要大的直流母线电容。三相交流电通过矩阵式变换器的一级变换就可以得到期望输出的42V直流电,能量传输密度比传统整流电路高。本文采用基于间接空间矢量调制的闭环控制策略,表明了其有效性,确保了输出电压的可调节性和在不同负载下高质量的输入电流。
基金Funded by the Natural Science Foundation of Hubei Province (No. 2004AA101E04)
文摘Fast response and stable torque output are crucial to the performance of electric screw presses. This paper describes the design of a direct torque control (DTC) system for speeding up torque response and reducing the starting current of electric screw presses and its application to the J58K series of numerical control electric screw presses with a dual-motor drive. The DTC drive system encompasses speed control, torque reference control, and switching frequency control. Comparison of the DTC dual-AC induction motor drive with corresponding AC servo motor drive showed that for the J58K-315 electric screw press, the DTC drive system attains a higher maximum speed (786 r/min) within a shorter time (1.13 s) during a 250 mm stroke and undergoes smaller rise in temperature (42.0 °C) in the motor after running for 2 h at a 12 min-1 strike frequency than the AC servo motor drive does (751 r/min within 1.19 s, and 50.6 °C rise). Moreover, the DTC AC induction motor drive, with no need for a tachometer or position encoder to feed back the speed or position of the motor shaft, enjoys increased reliability in a strong-shock work environment.