enow.com Web Search

Search results

1. Results from the WOW.Com Content Network

2. Variable-frequency drive - Wikipedia

   en.wikipedia.org/wiki/Variable-frequency_drive

   Small variable-frequency drive Chassis of above VFD (cover removed). A variable-frequency drive (VFD, or adjustable-frequency drive, adjustable-speed drive, variable-speed drive, AC drive, micro drive, inverter drive, variable voltage variable frequency drive, or drive) is a type of AC motor drive (system incorporating a motor) that controls speed and torque by varying the frequency of the ...

3. Vector control (motor) - Wikipedia

   en.wikipedia.org/wiki/Vector_control_(motor)

   In vector control, an AC induction or synchronous motor is controlled under all operating conditions like a separately excited DC motor. [21] That is, the AC motor behaves like a DC motor in which the field flux linkage and armature flux linkage created by the respective field and armature (or torque component) currents are orthogonally aligned such that, when torque is controlled, the field ...

4. Motor drive - Wikipedia

   en.wikipedia.org/wiki/Motor_drive

   A variable frequency drive (VFD) or variable speed drive (VSD) describes the electronic portion of the system that controls the speed of the motor. More generally, the term drive, describes equipment used to control the speed of machinery. Many industrial processes such as assembly lines must operate at different speeds for different products.

5. Electronic speed control - Wikipedia

   en.wikipedia.org/wiki/Electronic_speed_control

   An electronic speed control follows a speed reference signal (derived from a throttle lever, joystick, or other manual input) and varies the switching rate of a network of field effect transistors (FETs). [1] By adjusting the duty cycle or switching frequency of the transistors, the speed of the motor is changed. The rapid switching of the ...

6. Induction motor - Wikipedia

   en.wikipedia.org/wiki/Induction_motor

   Variable frequency drives implement the scalar or vector control of an induction motor. With scalar control, only the magnitude and frequency of the supply voltage are controlled without phase control (absent feedback by rotor position). Scalar control is suitable for application where the load is constant.

7. Direct torque control - Wikipedia

   en.wikipedia.org/wiki/Direct_torque_control

   Thus it is not possible to control the motor if the output frequency of the variable frequency drive is zero. However, by careful design of the control system it is possible to have the minimum frequency in the range 0.5 Hz to 1 Hz that is enough to make possible to start an induction motor with full torque from a standstill situation. A ...

8. Phase-locked loop - Wikipedia

   en.wikipedia.org/wiki/Phase-locked_loop

   Figure 1. Simple analog phase locked loop. A simple analog PLL is an electronic circuit consisting of a variable frequency oscillator and a phase detector in a feedback loop (Figure 1). The oscillator generates a periodic signal V o with frequency proportional to an applied voltage, hence the term voltage-controlled oscillator (VCO).

9. Synchronous Data Link Control - Wikipedia

   en.wikipedia.org/wiki/Synchronous_Data_Link_Control

   The first seven 1-bits of this (the pattern 01111111) constitute a "go-ahead" sequence (also called EOP, end of poll) giving a secondary permission to transmit. A secondary which wishes to transmit uses its 1-bit delay to convert the final 1 bit in this sequence to a 0 bit, making it a flag character, and then transmits its own frames.