Our company specializes in the export of electrical and electronic products like circuit breaker . ac dc contctors . thermal relay . wall switch & socket . energy saving lamp . signal lamps . pushbottons . meters and multitester as well as other electronic comonents and accesseries 公司以经营高低压成套电器产品进出口业务为主，兼营断路器、交直流接触器、继电器、仪器仪表、按钮信及号灯等中低器电子元器件。
The main works are organized as follows : a nine - order dynamic model is established for a single - machine infinite bus system with parallel ac / dc transmission lines , in which the dynamic regulating process of the generator , excitation controller and hvdc are considered comprehensively 论文的主要内容包括:基于单机无穷大交直流并联系统,综合考虑发电机、励磁控制器和直流输电系统的动态调节过程,建立九阶动态模型。
With the increased use of hvdc transmission systems in power systems , situations have arisen and will be even more frequent in the future , where sigle - infeed hvdc system with a parallel ac line and several hvdc systems are located in close of each other 随着hvdc输电系统在电力系统中投入越来越多，交直流并联系统和多馈入hvdc系统正在逐渐增多。在这种情况下，交流系统和直流系统，不同的hvdc系统间都将存在相互作用。
In chapter 5 , considering an ac / dc system that includes two dc lines . based on feedback linearization in the nonlinear systems and linear quadratic optimization control theory in the linear system , two new nonlinear additional controllers are designed in the same time 第五章针对包含两条直流传输线路的交直流互联系统，采用状态反馈精确线性化方法与线性系统的二次最优控制相结合的方法，同时设计了两条直流线路的非线性附加控制器。
Abstract : this paper introduces the working pinciples of the electro - economizer , in which either alternating or direct current voltage can be input with the adaption to the operating coils of contactor , steady direct current is output , and voltage auto - converting is absorbed and kept withno contacting point 文摘:论述了与交流接触器操作线圈适配的交直流输入(操作)电压通用，恒直流输出，吸合与保持电压无触点自动转换节电器的工作原理。
The conventional switching power supply usually use a diode rectifier followed by a bulk capacitor to convert ac voltage to dc voltage , resulting in the pulsating waveform of the input ac line current , low power factor ( generally 0 . 65 ) and high harmonic line current 传统的开关电源设备通常采用二极管桥来进行整流和一个较大的电解电容来进行滤波以实现输入电压的交直流转换，导致输入电流为一个很窄的脉冲波并含有较多的谐波分量，功率因数变低(通常只有0 . 65 ) 。
We utilize the mutual inductor to take a sample to the three - phase current , and sample which is enlarged , rectified , filtered , is send into pic single chip microcomputer to deal with . the size of three - phase current on the line is calculated out , which offer the accurate value for the change of controls the equipment state 利用互感器对三相电流取样，然后通过放大、整流、滤波，实现交直流转换，送入pic单片机处理，计算出温室输电线上三相电流大小，为控制设备状态的改变提供精确数值依据。
Promax tension ind corp has long sold and manufactured a variety of custo mized air shafts / air chucks / safety chucks , edge position control systems / epc , powder / air / disk brakes and clutches , ac / dc motor control systems , re - winding / un - winding systems , tension control systems , web inspection systems , automatic color register systems , servo - vector control systems , mmi interface and supervisory control and data acquisition ( scada ) systems and others such as slitting , winding , laminating , extruding , coating , and gravure printing machines , even other auxiliary devices etc . for webs such as paper , films , rubber , textiles and foils 本公司长久以来已经从事制造及销售有关纸类,薄膜,胶片,纺织品,橡胶等薄片卷材的卷筒物控制糸统周边设备,诸如气涨轴,气涨/安全夹头,边缘追踪器装置,磁粉/气压/碟式煞车器及离合器,交直流转矩马达控制系统,收放料车动系统,张力控制装置,印刷机静态观测器,自动套色控制装置,伺服向量控制系统,人机介面及监控系统及其他有关印刷,贴合,分条,复? ,涂布,上胶,押出,淋膜等产业机械
The operation principleresult of saving power ， mate rial and reliability of ac and dc usual auto - converting saving power instrument are expounded , which the operation - coil of ac contactor given ac and dc voltage is usual , output is even dc , on and off and keeping voltage non - contactor auto - convert 论述了与交流接触器操作线圈适配的交直流输入(操作)电压通用、恒直流输出、吸合与保持电压无触点自动转换节电器的工作原理；接触器配用节电器后的节能节材效果及节电器的可靠性。
A algorithm by curve - fitting is implemented in a microprocessor - based power supply installation . the design of hardware and software in detail is proposed and the relationship of time setting constant with heat model is simply discussed . the schemes above are applied to in a digital controlled power converter : ultimately test their feasibility and superiority 最后在集中上述技术的基础上研究和开发了一套精密交直流数控开关电源装置，经过对系统的各控制部分的软硬件设计与调试，实现了数字控制在精密智能电源模块系统中的应用，使之具有相当的稳定性和可靠性。
