Abstract:
A system for controlling a linear compressor, generates freezing force as a piston reciprocates according to rotation of a motor which receives alternating current power through a triac. The system includes a controller which moves up or delays a trigger signal corresponding to an absorption cycle or a compression cycle, such that the center point of the piston reaches a resonant point when a current and a phase difference of the motor deviate from predetermined ranges.
Abstract:
An apparatus for controlling an operation of a compressor includes a controller for generating a control signal for selecting an operation mode of a compressor according to an operation load of the compressor; a first switching unit connected to a motor consisting of a main coil and a sub-coil and selecting the main coil or both the main coil and the sub-coil according to the control signal; first and second capacitors electrically connected with the first switching unit; and a second switching unit connected to the first capacitor and selectively connecting the first capacitor in parallel to the second capacitor according to the control signal.
Abstract:
An apparatus and method for controlling an operation of a reciprocating compressor are disclosed. The apparatus for controlling an operation of a reciprocating compressor includes: a TDC/BDC detecting unit for detecting a TDC and a BDC of the reciprocating compressor; and a controller for independently controlling the TDC and the BDC so as to fit each reference position based on the detected TDC and BDC. Efficiency of the reciprocating compressor can be enhanced by independently controlling a top dead center and a bottom dead center.
Abstract:
A free-piston linear compressor (1) controlled to achieve high volumetric efficiency by a controller including an algorithm (116) for ramping up input power until piston-cylinder head collisions are detected using a detection algorithm (117/118) which then decrements power input whereupon input power is again ramped up by algorithm (116). Non-damaging low energy collisions are achieved by the controller including a perturbation algorithm (119) which perturbates the input power ramp with periodic transient pulses of power to ensure piston collisions are provoked during the transient power pulses.
Abstract:
A motor driving apparatus for driving a linear vibration motor having a spring member that supports a mover so as to form a spring vibration system including the mover. The motor driving apparatus employs an accurate spring constant of the spring member corresponding to an individual linear vibration motor at a position calculation for obtaining the position of the mover during the operation, thereby increasing the accuracy of the position calculation. The motor driving apparatus includes a mover force vibration unit for making the mover of the linear vibration motor freely vibrate, a relative position detection unit for detecting a timing when the freely vibrating mover passes through a fixed point (relative position), and a natural frequency detection unit for detecting a natural frequency of the mover based on output information from the relative position detection unit, thereby calculating the spring constant based on the detected natural frequency.
Abstract:
An apparatus and method are disclosed to control an operation of a reciprocating compressor capable of precisely controlling an operation (stroke) of a reciprocating compressor regardless of a parameter of an internal motor of the reciprocating compressor and a mechanical error of the reciprocating compressor. The apparatus for controlling an operation of a reciprocating compressor which determines a stroke estimate value corresponding to a point when a discharge valve of the reciprocating compressor is opened as a stroke reference value, and controls a voltage applied to the reciprocating compressor according to the determined stroke reference value.
Abstract:
An apparatus for controlling an operation of a reciprocating compressor includes a voltage detecting unit for detecting a positive half-wave voltage of an AC voltage applied to a motor of the reciprocating compressor; a current detecting unit for detecting a positive half-wave current of the AC current passing through the motor; a voltage and current estimating unit for estimating a negative half-wave voltage of the AC voltage applied to the motor and a negative half-wave current of the AC current passing through the motor based on the detected positive half-wave voltage and the detected positive half-wave current; a stroke estimating unit for estimating a stroke of the reciprocating compressor based on the detected positive half-wave voltage and the detected positive half-wave current and the negative half-wave voltage and the negative half-wave current which have been estimated by the voltage and the current estimating unit; a stroke controller for outputting a stroke control signal of the reciprocating compressor based on a comparison value between the estimate stroke estimate value and a stroke reference value of the reciprocating compressor; and a power source unit for applying positive DC power to the voltage detecting unit and the current detecting unit.
Abstract:
An apparatus for driving a linear vibration motor that employs a proper motor thrust constant value corresponding to each linear vibration motor at position calculation for obtaining the position of the mover of the linear vibration motor, thereby increasing the accuracy of the position calculation. This motor driving apparatus includes a motor driver for applying a DC voltage to the linear vibration motor, and a thrust detection unit for detecting a thrust of the mover, which is generated by the application of the DC voltage to the linear vibration motor, and calculates the thrust constant of the linear vibration motor according to an arithmetic operation of dividing the mover thrust detected by the thrust detection unit, by a value of a DC current that is supplied to the linear vibration motor due to the application of the DC voltage to the linear vibration motor.
Abstract:
Digital fluid pumps having first and second electromagnetic actuators formed in part by a piston to alternately drive the piston in opposite directions for pumping purposes. The piston motion is intentionally limited so that the electromagnetic actuators may operate with a high flux density to provide an output pressure higher than that obtained with conventional solenoid actuated pumps. The electromagnetic actuator coils are electrically pulsed for each pumping cycle as required to maintain the desired fluid flow and output pressure, with the piston being magnetically latchable at one or both extreme positions between pulses. Alternate embodiments and control methods and systems are disclosed.
Abstract:
An apparatus for controlling an operation of a reciprocating compressor includes a inductance increasing device connected to a motor of the reciprocating compressor, so that a surge current generated when power is applied to the reciprocating compressor at an initial stage is reduced and thus an initial stroke of the reciprocating compressor is reduced. Accordingly, operational efficiency of the reciprocating compressor is improved.