A method for operating a linear compressor includes substituting a first observed velocity, a bounded integral of the first observed velocity, an estimated clearance, an estimated discharge pressure, and an estimated suction pressure into the mechanical dynamic model for the motor, calculating an observed acceleration for the piston with the mechanical dynamic model for the motor, calculating a second observed velocity for the piston by integrating the observed acceleration for the piston, calculating an observed position of the piston by integrating the second observed velocity for the piston, and updating an estimated clearance, an estimated discharge pressure, and an estimated suction pressure based upon an error between the first and second observed velocities and an error between the bounded integral of the first observed velocity and the observed position.

A drive device is provided comprising a working pump, the working pump connected to a membrane fluid pump, and the working pump having a working piston able to oscillate axially between two reversal points for contracting and expanding a working chamber, and a control unit for controlling a movement of the working piston between the two reversal points. The controlled movement of the working piston comprises three temporally successive phases, in a first phase the working piston is accelerated to a speed that is greater than a speed at the end of the first phase, in a second phase the working piston is moved such that a specified speed of the working piston, a specified relative pressure in the working chamber, or a specified force of the working piston is substantially kept constant, and in a third phase the working piston is moved at a negative acceleration.

According to an embodiment, an apparatus for detecting a characteristic of a pump includes: a housing having a first planar surface and a second planar surface opposite the first planar surface, a mount structure located on the second planar surface, wherein the mount structure is configured to facilitate attachment of the apparatus on an external surface of the triplex pump, and wherein the mount structure avoids penetrating an inside surface of the triplex pump. Advantageously, apparatus is a non-invasive device and does not involve modifications to the pump nor opening the lid of the pump.

A linear compressor and methods of operation, for example, to detect polarity for the linear compressor are provided herein. The method may include supplying an initial time varying voltage to the motor of the linear compressor at an assumed polarity; estimating a first acceleration of the motor of the linear compressor when the motor is at a bottom dead center position; estimating a second acceleration of the motor of the linear compressor when the motor is at a top dead center position; comparing the first acceleration to the second acceleration; and determining whether the assumed polarity is correct based on the comparison.

A drive device is provided comprising a working pump, the working pump connected to a membrane fluid pump, and the working pump having a working piston able to oscillate axially between two reversal points for contracting and expanding a working chamber, and a control unit for controlling a movement of the working piston between the two reversal points. The controlled movement of the working piston comprises three temporally successive phases, in a first phase the working piston is accelerated to a speed that is greater than a speed at the end of the first phase, in a second phase the working piston is moved such that a specified speed of the working piston, a specified relative pressure in the working chamber, or a specified force of the working piston is substantially kept constant, and in a third phase the working piston is moved at a negative acceleration.

An integrated wireless data system including a wireless load cell assembly and method for measuring operational data of one or more components for safety, health monitoring, and control is provided. The wireless load cell assembly can include an energy storage device and may be configured to allow for bi-directional communication with a base unit to store operational parameters in a database for use in development of predictive maintenance techniques. The axial load cell can rotate freely for simple installation without regard to rotational orientation. A power management strategy and energy harvesting system are provided to ensure long term use of the wireless load cell assembly without the need to replace the energy storage device.

A method for operating a linear compressor includes substituting a first observed velocity, a bounded integral of the first observed velocity, an estimated clearance, an estimated discharge pressure, and an estimated suction pressure into the mechanical dynamic model for the motor, calculating an observed acceleration for the piston with the mechanical dynamic model for the motor, calculating a second observed velocity for the piston by integrating the observed acceleration for the piston, calculating an observed position of the piston by integrating the second observed velocity for the piston, and updating an estimated clearance, an estimated discharge pressure, and an estimated suction pressure based upon an error between the first and second observed velocities and an error between the bounded integral of the first observed velocity and the observed position.

A method for operating a linear compressor is provided. The method includes estimating an acceleration of the motor of the linear compressor using at least a robust integral of the sign of the error feedback. A position of the motor of the linear compressor when the motor of the linear compressor is at the bottom dead center point is also determined based at least in part on a measured current to the motor of the linear compressor and an estimated acceleration of the motor. The position of the motor of the linear compressor when the motor of the linear compressor is at a top dead center point is calculated based at least in part on the position of the motor of the linear compressor when the motor of the linear compressor is at the bottom dead center point and a stroke length of the motor of the linear compressor.

Provided for may be a motor speed control apparatus for use with a piston pump. The piston may be adapted to create a plurality of compressions and the piston may have a compression path and a decompression path. Further, the piston cylinder may include a proximal end, a distal end, and a piston length. The piston cylinder may have a proximal threshold position and a distal threshold position. In an embodiment, the apparatus includes a proximal and a distal hall effect sensor. The apparatus may comprise a computer, wherein instructions instruct the piston to decelerate at the distal threshold position during the compression path and the proximal threshold position during the decompression path, and/or wherein the computer executable instructions instruct the piston to accelerate at the distal threshold position during the decompression path and the proximal threshold position during the compression path.

An integrated wireless data system including a wireless load cell assembly and method for measuring operational data of one or more components for safety, health monitoring, and control is provided. The wireless load cell assembly can include an energy storage device and may be configured to allow for bi-directional communication with a base unit to store operational parameters in a database for use in development of predictive maintenance techniques. The axial load cell can rotate freely for simple installation without regard to rotational orientation. A power management strategy and energy harvesting system are provided to ensure long term use of the wireless load cell assembly without the need to replace the energy storage device.