公开(公告)号：US4437050A

公开(公告)日：1984-03-13

申请号：US445647

申请日：1982-11-30

Applicant: John K. Overzet

Inventor： John K. Overzet

IPC: H02M5/458 ,  H02P27/06 ,  H02P7/42

CPC classification number: H02P27/06 ,  H02M5/4585 ,  H02P2201/03 ,  H02P27/047

Abstract: Stabilized operation of an inverter and an a-c motor, driven by the inverter, is obtained in the presence of sudden undesired load changes by controlling the inverter so that both the amplitude and frequency of the inverter output a-c voltage will be functions of, and will vary directly with, the d-c bus voltage, with the result that anytime an abrupt abnormal load change causes the d-c bus voltage to vary, a frequency change occurs to compensate for the load change and to stabilize the bus voltage. By employing the d-c bus voltage to regulate the inverter frequency, if there is a sudden decrease, for example, in the mechanical load on the motor, the d-c bus voltage, which will tend to increase, causes the frequency of the inverter output voltage to increase, thereby increasing the motor speed so that the electrical load change across the d-c bus is reduced. As a result, the d-c bus voltage tends to remain relatively constant in spite of the abrupt mechanical load change. When there is a normal variation in load demand, necessitating a different steady state motor speed, a set point or reference voltage may be adjusted to change the amplitude and frequency of the inverter output voltage to the levels needed to drive the motor at the new required speed.

Abstract translation: 逆变器和交流电动机由变频器驱动的稳定运行通过控制逆变器在突然不希望的负载变化的情况下获得，使逆变器输出交流电压的幅度和频率都将变为功能，并将变化 直流总线电压，结果是任何时候突然的异常负载变化导致直流总线电压发生变化，发生频率变化以补偿负载变化并稳定总线电压。 通过采用直流母线电压来调节变频器的频率，如果电机的机械负载有突然的下降，直流母线电压会增加，导致变频器输出电压的频率 从而增加电动机速度，从而减小直流总线上的电负载变化。 结果，尽管突然的机械负载变化，d-c总线电压趋于保持相对恒定。 当负载需求正常变化时，需要不同的稳态电机速度，可以调整设定点或参考电压，以将变频器输出电压的幅度和频率改变到以新的要求驱动电机所需的电平 速度。

公开(公告)号：US4139885A

公开(公告)日：1979-02-13

申请号：US808203

申请日：1977-06-20

Applicant: John K. Overzet ,  George H. Studtmann

Inventor： John K. Overzet ,  George H. Studtmann

IPC: H02M5/45 ,  H02M1/18

CPC classification number: H02M5/4505

Abstract: An a-c supply system includes an input bridge circuit, connected to receive a-c input voltage and produce an output d-c voltage which is passed through a filter to an inverter having a plurality of thyristor switches, which switches are regulated to produce an a-c output voltage for supplying a load. If two of the switches are inadvertently triggered on to produce a fault across the bus, the rapid discharge of the filter capacitor into this fault is sensed, and the protection circuit provides both simultaneous turn-on of all of the inverter power switches, and turn-off of the input bridge. The input bridge turn-off is achieved by simultaneous removal of the gate drive from all the power switches in the input bridge and commutation of all the power switches in the input bridge circuit, or by interrupting power transfer from the input bridge toward the inverter. In addition to sensing the filter capacitor current, the level of current supplied to the input bridge is monitored so that a sudden rise is detected and utilized to initiate the same protective functions.

Abstract translation: 交流电源系统包括输入桥接电路，其连接以接收交流输入电压并产生输出直流电压，该输出直流电压通过滤波器到具有多个晶闸管开关的逆变器，该开关被调节以产生用于供应的交流输出电压 负载。 如果两个开关被无意中触发，从而在总线上产生故障，就会检测到滤波电容器迅速放电到该故障中，并且保护电路同时提供所有逆变器电源开关的同时开启，并转向 - 输入桥。 输入桥关断是通过同时从输入桥中的所有功率开关和输入桥电路中的所有功率开关的整流同时去除栅极驱动，或者通过中断从输入桥到逆变器的功率传递来实现的。 除了检测滤波电容器电流之外，还监控提供给输入电桥的电流电平，以便检测到突然上升并利用它来启动相同的保护功能。