English:
[0001] The subject matter disclosed herein relates to motor control systems, particularly motor control systems in cooling systems.
[0002] FIG. 1 illustrates a prior art example of a motor control system. The system includes a variable frequency drive (VFD) 102 connected to an alternating current (AC) power source 104. The VFD 102 includes a rectifier 106 connected to a direct current (DC) bus 108, an inverter 110 and a VFD controller 109. The inverter is connected to a chiller motor 112. A motor controller 114 is mechanically connected to a chiller compressor 116 and is communicatively connected to the AC power source 104 and the chiller motor 112 via the VFD controller 109 and the inverter 110.
[0004] If AC power is lost to the system, the charge stored in the capacitor continues to power the chiller motor however; the motor controller may not receive power and may shutdown.
[0006] According to another aspect of the invention, a method for controlling a system includes receiving alternating current (AC) power from an AC power source, rectifying the AC power into direct current (DC) power, charging a capacitor with the DC power, inverting DC power from the capacitor into AC power, and outputting AC power to a chiller motor and a motor controller.
[0007] According to yet another aspect of the invention, a chiller system includes a variable frequency drive unit connected to an alternating current (AC) power source, a chiller motor connected to the variable frequency drive unit, the chiller motor operative to receive AC power from the variable frequency drive unit, an inverter connected to the variable frequency drive unit, the inverter operative to receive DC power from the variable frequency drive unit and output AC power, and a motor controller connected to the inverter and the chiller motor, the motor controller operative to receive AC power from the inverter and send a control signal to the chiller motor.
[0008] These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings.
[0009] The subject matter, which is regarded as the invention, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
[0010] FIG. 1 illustrates a prior art example of a motor control system.
[0011] FIG. 2 illustrates an exemplary embodiment of a motor control system.
[0013] FIG. 2 illustrates an exemplary embodiment of a motor control system 200. The system includes a variable frequency drive unit (VFD) 202 that is connected to an AC power source 204. The VFD 202 includes a rectifier 206 connected to a DC bus 208, an inverter 210, and a VFD controller 209. The DC bus 208 includes a capacitor. The system 200 includes a chiller motor 212 mechanically connected to a chiller compressor unit 216. The VFD 202 is connected to an inverter 213 that is connected to a motor controller 214. The chiller motor 212 is connected to the VFD 202 and the motor controller 214 via the VFD controller 209 and the inverter 210. In alternate embodiments, the motor controller 214 may send control signals to the chiller motor 212 directly via the inverter 210, bypassing the VFD controller 209.
[0014] In operation, the rectifier 206 receives AC power from the AC power source 204. The rectifier 206 rectifies the AC power into DC power that charges the capacitor in the DC bus 208. The inverter 210 receives DC power from the capacitor in the DC bus 208 and outputs AC power to drive the chiller motor 212. The inverter 213 receives DC power from the capacitor in the DC bus 208 and outputs AC power to the motor controller 214. The motor controller 214 sends control signals to the chiller motor 212 via the VFD controller 209. The chiller motor mechanically drives the chiller compressor unit 216. Alternatively, the motor controller 214 may send control signals directly to the chiller motor 212, bypassing the VFD controller 209.
[0015] If AC power is lost from the AC power source 204, the capacitive charge stored in the capacitor in the DC bus 208 continues to supply DC power to the inverters 210 and 213 that output AC power to the chiller motor 212 and the motor controller 214 respectively. Supplying both the chiller motor 212 and the motor controller 214 with power from the same source— the capacitor in the DC bus 208— allows both the motor controller 214 and the chiller motor 212 to continue synchronous operation in the event of a loss of AC power.
[0016] In the illustrated embodiment, the capacitor in the DC bus 208 is sized to store a capacitive charge that may drive the chiller motor 212 and power the motor controller 214 for approximately 5-15 minutes in the event of a loss of AC power. The parameters described above are mere examples. Alternate systems may include any appropriate design parameters depending on power specifications.
[0017] While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.

中文:
[0001]这里公开的主题涉及电动机控制系统,尤其是冷却系统中的电动机控制系统。
[0002]图1图示了电动机控制系统的现有技术示例。该系统包括被连接到交流电(AC)电源104的可变频率驱动(VFD)102。VFD 102包括被连接到直流电(DC)总线108的整流器106、逆变器110和VFD控制器109。逆变器被连接到制冷机电动机112。电动机控制器114被机械地连接到制冷机压缩机116并经由VFD控制器109和逆变器110可通信地被连接到AC电源104和制冷机电动机112。
[0004]如果AC功率对系统不再可用,那么在电容器中存储的电荷继续对制冷机电动机进行供电,然而电动机控制器可能不接收功率并可能关闭。
[0006]根据本发明的另一方面,一种用于控制系统的方法包括:从AC电源接收交流电(AC)功率;将所述AC功率整流成直流电(DC)功率;利用所述DC功率对电容器进行充电;将来自所述电容器的DC功率变换成AC功率;以及向制冷机电动机和电动机控制器输出AC功率。
[0007]根据本发明的又一个方面,一种制冷机系统包括:被连接到交流电(AC)电源的可变频率驱动单元;被连接到所述可变频率驱动单元的制冷机电动机,所述制冷机电动机可操作的用于从所述可变频率驱动单元接收AC功率;被连接到所述可变频率驱动单元的逆变器,所述逆变器可操作的用于从所述可变频率驱动单元接收DC功率并输出AC功率;以及被连接到所述逆变器和所述制冷机电动机的电动机控制器,所述电动机控制器可操作的用于从所述逆变器接收AC功率并向所述制冷机电动机发送控制信号。
[0008]这些以及其他优点和特征将根据结合了附图的以下描述而变得更显而易见。
[0009]在本说明书的结尾处,在权利要求中特别地指出并清楚地要求被看作为本发明的主题。本发明的前述特征和其他特征以及优点,根据结合了附图的以下详细描述是显而易见的,在附图中:
[0010]图1图示了电动机控制系统的现有技术示例。
[0011]图2图示了电动机控制系统的示例性实施例。
[0013]图2图示了电动机控制系统200的示例性实施例。该系统包括:被连接到AC电源204的可变频率驱动单元(VFD)202。VFD 202包括被连接到DC总线208的整流器206、逆变器210和VFD控制器209。DC总线208包括电容器。该系统200包括被机械地连接到制冷机压缩机单元216的制冷机电动机212。VFD 202被连接到逆变器213,该逆变器213被连接到电动机控制器214。制冷机电动机212经由VFD控制器209和逆变器210被连接到VFD 202和电动机控制器214。在可替换的实施例中,电动机控制器214可以绕过VFD控制器209直接地经由逆变器210向制冷机电动机212发送控制信号。
[0014]在工作中,整流器206从AC电源204接收AC功率。整流器206将AC功率整流成DC功率,该DC功率对DC总线208中的电容器进行充电。逆变器210从DC总线208中的电容器接收DC功率并输出AC功率以驱动制冷机电动机212。逆变器213从DC总线208中的电容器接收DC功率并向电动机控制器214输出AC功率。电动机控制器214经由VFD控制器209向制冷机电动机212发送控制信号。制冷机电动机机械地驱动制冷机压缩机单元216。可替换地,电动机控制器214可以绕过VFD控制器209直接地向制冷机电动机212发送控制信号。
[0015]如果AC功率从AC电源204失去,那么在DC总线208中的电容器中存储的电容性的电荷继续向逆变器210和213供应DC功率,该逆变器210和213分别向制冷机电动机212和电动机控制器214输出AC功率。在如果发生失去AC功率的情况下,使用来自同一个源—DC总线208中的电容器—的功率供应制冷机电动机212和电动机控制器214这两者允许电动机控制器214和制冷机电动机212这两者继续同步工作。
[0016]在已说明的实施例中, DC总线208中的电容器的大小被设置成存储电容性的电荷,该电容性的电荷在如果发生失去AC功率的情况下可以驱动制冷机电动机212并对电动机控制器214进行供电达大约5-15分钟。以上描述的参数仅仅是示例。可替换的系统可以包括取决于功率规格的任何适当的设计参数。
[0017]虽然已经结合有限数量的实施例详细描述了本发明,但应当容易理解的是,本发明不限于这样公开的实施例。相反地,本发明可以被修改成结合迄今未描述的但与本发明的精神和范围相称的任意数量的变形、变更、替换或等效布置。另外,虽然已经描述了本发明的各种实施例,但应当理解的是,本发明的多个方面可以仅包括所描述的实施例中的一些。因此,不应将本发明视为受限于以上描述,而是仅受限于所附权利要求的范围。