Abstract: Angular speed of a rotor of an induction motor without an encoder for rotor position and speed sensing is controlled by first sensing stator currents and voltages of the induction motor. A dynamic gain estimator is designed by applying a state transformation to a model of the induction motor. A states of the induction motor is estimated by applying the dynamic gain estimator to the currents and the voltages, and then the state is used to control the angular speed of the rotor of the induction motor.

Abstract: A vapor compression system includes a heat exchanger having an inlet header pipe connected to a set of paths for passing refrigerant to condition a controlled zone. The inlet header pipe splits the refrigerant into different paths. An amount of the refrigerant entering the inlet header pipe is controlled by a valve. The vapor compression system also includes a set of sensors for measuring temperatures of the refrigerant in each path of the set of paths and a controller including a processor for determining a position of the valve based on the measurements of at least one sensor from the set of sensors and a thermal capacity requested for the heat exchanger.

Abstract: A method of coordinated flow control in a heat exchanger system includes adjusting a position of a variable actuator of the heat exchanger system if an associated monitored temperature of the heat exchanger system needs adjustment, determining if the adjusted position of the variable actuator is within a predetermined range of positions, adjusting a position of a discrete actuator of the heat exchanger system if the adjusted position of the variable actuator is not within the predetermined range of positions, and resetting the position of the variable actuator in response to adjusting the position of the discrete actuator.

Abstract: An operation of a processing machine with redundant actuators is controlled according to a reference trajectory by selecting, from a set of points forming a segment of the reference trajectory to be processed for a period of time, a subset of points corresponding to a fraction of the period of time. The subset of points is selected such that the redundant actuators are capable to position the worktool at each point in the subset within the period of time and are capable to maintain the worktool at the last point of the subset after the period of time while satisfying constraints on motion of the redundant actuators. The segment of the reference trajectory is modified in the time domain and the control inputs for controlling the motion of the redundant actuators are determined using the modified segment of the reference trajectory.

Abstract: A system includes a heat exchanger; a variable actuator in operative communication with the heat exchanger and configured to vary a flow of a first fluid through the heat exchanger in a continuous manner; a discrete actuator in communication with the heat exchanger and configured to vary a flow of a second fluid through the heat exchanger at one of at least two discrete rates; and a controller in communication with the variable actuator and the discrete actuator, wherein the controller is configured to adjust the position of the variable actuator within a range dependent upon a current position of the discrete actuator.

Abstract: A method calibrates a laser processing machine by commanding a scan head to direct a laser beam to a desired position, then senses an actual position of the laser beam directly using a position sensitive detector (PSD) after the scan head is positioned. A relative position between the scan head and PSD is altered using one or more linear actuators. A position feedback loop is closed around the linear actuators so that the relative position of the laser beam on the PSD is reduced to zero. The actual position of the laser spot is then measured indirectly by encoders attached to linear axes of the laser processing machine. The actual position is stored in a memory. An error is determined as a difference between the desired position and the actual position. Compensation coefficients are determined from the error and stored for later use during operation of the laser processing machine.

Abstract: Angular speed of a rotor of an induction motor without an encoder for rotor position and speed sensing is controlled by first sensing stator currents and voltages of the induction motor. A dynamic gain estimator is designed by applying a state transformation to a model of the induction motor. A states of the induction motor is estimated by applying the dynamic gain estimator to the currents and the voltages, and then the state is used to control the angular speed of the rotor of the induction motor.

Abstract: A method computes reference signals for a machine with redundant positioning by first generating a reference trajectory according to an ordered list of points. Then, using a filter or by choosing the value of the reference at each sampling time, a reference trajectory for the slow subsystem is produced. Next, determine whether the reference trajectory and the slow subsystem reference trajectory violate feasibility constraints, and if true, slowing down the reference trajectory and repeating with the generation of the slow subsystem reference trajectory. The slow subsystem reference trajectory is sent, via a model predictive control block, to a slow positioning subsystem controller, and a combination of the slow subsystem reference trajectory and the reference trajectory is sent to a fast positioning subsystem controller.

Abstract: A vapor compression system includes a heat transfer system including an arrangement of components moving a refrigerant through a vapor compression cycle to condition a controlled environment and a refrigerant management system including at least one expansion device regulating an amount of the refrigerant in the vapor compression cycle. The vapor compression system also includes a controller including a processor jointly controlling the expansion device and at least one component of the heat transfer system according to a metric of performance of the vapor compression system.

Abstract: A method for controlling an operation of a vapor compression system (VCS) determines values of measured outputs of the operation of the VCS that include performance and constrained outputs. The method determines states of the VCS using an estimator model of the VCS defining a relationship between the states of the VCS, control inputs and controlled outputs, such that a difference between outputs predicted using the estimator model and the measured outputs asymptotically approaches zero. The states of the VCS include a main state representing the operation of the VCS and an auxiliary state representing the effect of unknown disturbances on each measured output of the VCS. The control inputs for controlling the operation of the VCS are determined using a prediction model, such that the constrained output satisfies the constraints, and a difference between the performance output and the value of the setpoint asymptotically approaches zero.

Abstract: A multi-zone vapor compression system (MZ-VCS) includes a compressor connected to a set of heat exchangers controlling environments in a set of zones, a supervisory controller determining a set of control inputs for controlling a vapor compression cycle of the MZ-VCS, and a set of capacity controllers. The supervisory controller is a model predictive controller (MPC) determining the set of control inputs using a model of the MZ-VCS including a linear relationship between thermal capacities of each heat exchanger and temperatures in a corresponding zone controlled by the heat exchanger. Each capacity controller enforces the linear relationship between the thermal capacity and the temperature in the corresponding zone.

Abstract: A method controls a vapor compression system including a variable speed compressor. A desired discharge temperature of the compressor is determined using a mapping between values of the discharge temperature of the compressor and values of speed of the compressor and outdoor air temperature. A transition function for transitioning a current discharge temperature to the desired discharge temperature is determined, such that the transition function is continuous and a rate of change of the transition function is limited. Next, a valve of the vapor compression system is controlled such that the discharge temperature is transitioned to the desired discharge temperature based on the transition function.

Abstract: A method controls discharge temperature of a compressor of a vapor compression system. Using a mapping among discharge temperature, speed of the compressor, and outdoor air temperature, the method determines a desired discharge temperature for a new value of the speed of the compressor. The compressor is abruptly controlled to change the current speed of the compressor to the new value. A valve of the vapor compression system is smoothly controlled, such that the discharge temperature is transitioned to the desired discharge temperature according to a function of time representing a low pass filter with a time constant proportional to the thermal time constant of the compressor.

Abstract: A motion-control system for moving a mass according to different tasks includes at least one controllable actuator for performing the different tasks and an input module for receiving a specific task to perform. The system also includes a controller for controlling a performance of the specific task by the controllable actuator according to a specific control law and a tunable actuator having a tunable parameter of mechanical response, wherein the tunable actuator is mechanically arranged in the system, such that different values of the tunable parameter change dynamics of the system. An optimization module of the system jointly selects a value of the tunable parameter and the specific control law based on the specific task.

Abstract: A branch controller operates with a system for temperature and humidity control. The branch controller includes a fluid control system for controlling a flow of the liquid desiccant in an arrangement of channels forming a first path for exchanging the liquid desiccant between a liquid desiccant conditioning unit and at least a first space conditioning unit and a second path for directing the liquid desiccant received from the first space conditioning unit to a second space conditioning unit. The branch controller includes a processor for comparing operational conditions of the first space conditioning unit and the second space conditioning unit. The processor selects between the first path and the second path based on the comparison and commands the fluid control system to control the flow of the liquid desiccant according to the selected path.

Abstract: A vapor compression system includes a heat exchanger having an inlet header pipe connected to a set of paths for passing refrigerant to condition a controlled zone. The inlet header pipe splits the refrigerant into different paths. An amount of the refrigerant entering the inlet header pipe is controlled by a valve. The vapor compression system also includes a set of sensors for measuring temperatures of the refrigerant in each path of the set of paths and a controller including a processor for determining a position of the valve based on the measurements of at least one sensor from the set of sensors and a thermal capacity requested for the heat exchanger.

Abstract: An operation of a processing machine with redundant actuators is controlled according to a reference trajectory by selecting, from a set of points forming a segment of the reference trajectory to be processed for a period of time, a subset of points corresponding to a fraction of the period of time. The subset of points is selected such that the redundant actuators are capable to position the worktool at each point in the subset within the period of time and are capable to maintain the worktool at the last point of the subset after the period of time while satisfying constraints on motion of the redundant actuators. The segment of the reference trajectory is modified in the time domain and the control inputs for controlling the motion of the redundant actuators are determined using the modified segment of the reference trajectory.

Abstract: An operation of a system is controlled according to a control trajectory represented by a solution of a set of differential equations satisfying boundary conditions, wherein the set of differential equations includes ordered piecewise differential equations. The set of differential equations is parameterized to produce a first set of parameters representing values of the solution at switching times and a second set of parameters representing values of the switching times. The first and the second sets of parameters are determined alternately until the boundary conditions are satisfied to produce the solution; and the control trajectory is generated based on the solution to control the operation of the system.

Abstract: A method controls redundant actuators of a machine based on a reference trajectory. The method determines a cost function representing operations of the redundant actuators and minimizes the cost function subject to constraints to produce a sequence of commands for each actuator. The redundant actuators are controlled according to the sequences of commands.

Abstract: A method controls a set of semi-active actuators arranged in an elevator system represented with a model of a virtual elevator system having a single virtual semi-active actuator arranged to compensate a virtual disturbance proportional to a sum of disturbances from the set of disturbances. The method determines the virtual disturbance during an operation of the elevator car using a motion profile of position of the elevator car during the operation and a disturbance profile of the virtual disturbance, and determines amplitude of a virtual force of the virtual semi-active actuator using the model and the virtual disturbance. A gain of a controller for controlling the set of semi-active actuators is adjusted based on the amplitude of the virtual force and a reference force of the virtual semi-active actuator.