Disclosed is a disconnection detection apparatus of a sinusoidal wave signal. The disconnection detection apparatus of the present disclosure converts a first sinusoidal wave and a second sinusoidal wave into absolute values, respectively, and determines that disconnection occurs when a value of the first sinusoidal wave is less than a first comparison value that is greater than a minimum value and a value of the second sinusoidal wave is less than a second comparison value that is less than a maximum value.

A closed-loop system may include a plant (an electric machine requiring control) and a fractional-order proportional-resonant controller. The fractional-order proportional-resonant controller may have an order greater than zero and less than or equal to one. The order for the fractional-order proportional-resonant controller may be selected to yield a target amplitude and target slope for frequency response. The frequency response may be such that a steady-state error associated with a speed of the electric machine is inversely proportional to the target amplitude and less than a predetermined threshold. The order of the controller may be 0.9.

A closed-loop system may include a plant (an electric machine requiring control) and a fractional-order proportional-resonant controller. The fractional-order proportional-resonant controller may have an order greater than zero and less than or equal to one. The order for the fractional-order proportional-resonant controller may be selected to yield a target amplitude and target slope for frequency response. The frequency response may be such that a steady-state error associated with a speed of the electric machine is inversely proportional to the target amplitude and less than a predetermined threshold. The order of the controller may be 0.9.

A control device includes: an angular velocity detection unit that detects an angular velocity of a motor; a vibration component removal unit that removes a vibration component in a predetermined band from the angular velocity detected by the angular velocity detection unit by filtering; and a current command calculation unit that calculates a current command value of a drive current for driving the motor according to a torque command value and the angular velocity from which the vibration component has been removed by the vibration component removal unit.

A control device includes: an angular velocity detection unit that detects an angular velocity of a motor; a vibration component removal unit that removes a vibration component in a predetermined band from the angular velocity detected by the angular velocity detection unit by filtering; and a current command calculation unit that calculates a current command value of a drive current for driving the motor according to a torque command value and the angular velocity from which the vibration component has been removed by the vibration component removal unit.

A display including a supporting stand and a display panel is provided. The supporting stand has a rotating assembly, a drive motor, and a microcontroller. The display panel has a computing device. The drive motor is connected to the rotating assembly for driving the rotating assembly to rotate. The microcontroller is coupled to the drive motor for controlling the drive motor. The display panel is disposed on the rotating assembly. The computing device is coupled to the microcontroller. The computing device is configured to read an image. The computing device transmits a signal to the microcontroller based on an orientation of the image being portrait or landscape so that the microcontroller switches on the drive motor and the rotating assembly drives the display panel to rotate relative to the supporting stand for switching a rotating position of the display panel to a portrait mode or a landscape mode.

For this invention I took into account two basic aspects: the application of induction motors its speeds and the weight of children newly born until 3 years old.

The present invention will have as components; the induction motor specifically of single phase power, a support structure, a bed or a seat.

For this invention, the dimensions of the induction motor, such as, the stator, the rotor, the shaft and its length, the speeds, will be according to the weight of children's between age 0 to 3 years old. The two speeds that will have will be slower than those of the fans of home and commercial establishments. These are the modifications that will be made in the single phase induction motor.

The new section on invention is the bed or the seat that will be connected to the shaft to allow the bed to rotate.

Another new aspect of the invention is the support structure in which the motor will be placed in a vertical position. The support structure will be circular and with a certain height. Therefore the bed will be also circular, rectangular or another configuration.

The induction motor inside the support structure will be permanent, while the bed can be mounted or disassembled as well as the seat.

For this invention I took into account two basic aspects: the application of induction motors its speeds and the weight of children newly born until 3 years old.

The present invention will have as components; the induction motor specifically of single phase power, a support structure, a bed or a seat.

For this invention, the dimensions of the induction motor, such as, the stator, the rotor, the shaft and its length, the speeds, will be according to the weight of children's between age 0 to 3 years old. The two speeds that will have will be slower than those of the fans of home and commercial establishments. These are the modifications that will be made in the single phase induction motor.

The new section on invention is the bed or the seat that will be connected to the shaft to allow the bed to rotate.

Another new aspect of the invention is the support structure in which the motor will be placed in a vertical position. The support structure will be circular and with a certain height. Therefore the bed will be also circular, rectangular or another configuration.

The induction motor inside the support structure will be permanent, while the bed can be mounted or disassembled as well as the seat.

An electric motor system includes a drive shaft, a first electric motor, a second electric motor, a first inverter, a second inverter and a control unit. The drive shaft is rotatable around an axis. The first electric motor and the second electric motor rotate the drive shaft. The first inverter supplies power in order to generate a torque to the first electric motor. The second inverter supplies power in order to generate a torque to the second electric motor. The control unit controls the first inverter and the second inverter. The controller is configured to be able to change a ratio between an output torque of the first electric motor and an output torque of the second electric motor.

In summary, the invention relates to a device and method for open-loop or closed-loop control of a movement of a die cushion of a die cushion press. The device has a control value encoder (11), a speed controller (12), a current controller (13), and a motor control device (14) for providing a nominal current for an electrical drive (15) of a fluid-hydraulic motor pump unit (20) for moving a die cushion of a die cushion press. The control value encoder (11) is provided in order to calculate a setpoint speed based on a die cushion control value command and a die cushion information. The speed controller (12) calculates a setpoint current based on the setpoint speed. The current controller (13) calculates a control signal based on the setpoint current, and the motor control device (14) calculates the nominal current based on the control current. In this respect, the dynamics of the control of the electrical machine can be improved.