Abstract: A feedback controller for generating and using a normalized performance index for a feedback control loop is shown and described. The feedback controller is configured to generate an input for a control process, identify an error signal representing a difference between a setpoint and a feedback signal from the control process, compute a first exponentially-weighted moving average (EWMA) of a first function of the error signal and a second EWMA of a second function of the error signal, and to generate a normalized performance index using the first EWMA and the second EWMA.

Abstract: A method for adaptively and automatically adjusting a sampling rate in a feedback control system includes monitoring an error signal for a disturbance event, evaluating the error signal in response to the disturbance event to estimate a time constant of a control process, and determining a sampling rate for use in the feedback control system based on the estimated time constant. The error signal may be based on a difference between a setpoint and a feedback signal and the feedback signal may be received from the control process.

Abstract: A method for pairing a first wireless device with a second wireless device includes gathering a first wireless communications characteristic about communications between the first wireless device and the second wireless device. The method further includes gathering second wireless communications characteristics about communications between the first wireless device and at least one wireless device other than the second wireless device. The method further includes generating a relative gain array from the communications characteristics and computing the pairing between the first wireless device and the second wireless device using the generated relative gain array. The method further includes configuring the first wireless device and/or the second wireless device based on the computed pairing.

Abstract: A system for detecting a control loop interaction between two or more control loops. The system includes a processing circuit configured to store a history of detected loop disturbances for a plurality of control loops. The processing circuit is also configured to compute a measure of interaction between control loops using the history of detected loop disturbances. The processing circuit is further configured to determine whether a loop interaction exists based on the computed measure of interaction.

Abstract: A method for pairing a first wireless device with a second wireless device includes gathering a first wireless communications characteristic about communications between the first wireless device and the second wireless device. The method further includes gathering second wireless communications characteristics about communications between the first wireless device and at least one wireless device other than the second wireless device. The method further includes generating a matrix using the first and second wireless communications characteristics and generating a relative gain array from the matrix and computing the pairing between the first wireless device and the second wireless device using the generated relative gain array. The method further includes configuring the first wireless device and/or the second wireless device based on the computed pairing.

Abstract: A method of evaluating the performance of a control system using a computerized device includes calculating a ratio of a first area and a second area associated with a peak value of a signal associated with the control system, comparing the ratio with a predetermined value for the ratio, determining a cause of oscillation in the control system based on the comparison of the ratio with the predetermined value for the ratio, and providing a diagnosis of the cause of oscillation in the control system.

Abstract: A monitoring system, including an interface configured to communicate with a building device, a sensor, and a memory. The monitoring system includes a processor configured to communicate with the memory and the interface. The processor is configured to transmit a test signal to at least one of the building device and the sensor. The processor is further configured to receive a return signal from at least one of a building device signal and a sensor signal. Further, the processor is configured to associate the building device to the sensor based on the return signal.

Abstract: A method of and apparatus for evaluating the performance of a control system are disclosed. The method of evaluating the performance of a control system includes calculating a ratio of a first area associated with the signal and a second area associated with the signal. The method also includes comparing the ratio with a predetermined value and determining a cause of an oscillation in the control system based on the comparison. The apparatus for evaluating the performance of a control system includes a processor operable to execute a first function configured to calculate a ratio of a first area associated with the signal and a second area associated with the signal. The first function is also configured to compare the ratio with a predetermined value and determine a cause of oscillation in the control system based on the comparison.

Abstract: A method and apparatus of identifying a system is disclosed. The method comprises estimating at least one parameter in a second-order model of the system, and approximating at least one parameter in a first-order model of the system from the at least one second-order model parameter. The method may also comprise sampling an input to the system, sampling an output from the system. The apparatus comprises a device for estimating at least one parameter in a second-order model of the system, and device for approximating at least one parameter in a first-order model of the system from the at least one second-order model parameter.

Abstract: A method for pairing a first wireless device with a second wireless device includes gathering a first wireless communications characteristic about communications between the first wireless device and the second wireless device. The method further includes gathering second wireless communications characteristics about communications between the first wireless device and at least one wireless device other than the second wireless device. The method further includes generating a matrix using the first and second wireless communications characteristics and generating a relative gain array from the matrix and computing the pairing between the first wireless device and the second wireless device using the generated relative gain array. The method further includes configuring the first wireless device and/or the second wireless device based on the computed pairing.

Abstract: A monitoring system, including an interface configured to communicate with a building device, a sensor, and a memory. The monitoring system includes a processor configured to communicate with the memory and the interface. The processor is configured to transmit a test signal to at least one of the building device and the sensor. The processor is further configured to receive a return signal from at least one of a building device signal and a sensor signal. Further, the processor is configured to associate the building device to the sensor based on the return signal.

Abstract: A method of evaluating the performance of a control system using an electronic device having state machine logic. The state machine logic includes determining a first logic state representative of a first condition of the control system based on data received from the control system. The state machine logic also includes executing a first testing function and transitioning to a second logic state representative of a second condition of the control system based on at least one of the received data and output from the first testing function. The state machine logic further includes executing a second testing function and providing a diagnosis of the performance of the control system based on the output of at least one of the first testing function and the second testing function.

Abstract: A system and method for controlling a controlled parameter that affects a target parameter of a target zone is disclosed. The method comprises providing a feedback control loop having a switching controller, a controlled device, and an averaging device. The controlled device comprises a time constant and a specified operational characteristic. The controlled device comprises a first operational state and a second operational state. The method further comprises calculating a time constant for the averaging device based at least on the time constant for the controlled device, and the specified operational characteristic. The specified operational characteristic may comprises a minimum amount of time that the controlled device operates before it can be switched between the first operational state and the second operational state.

Abstract: A method for and apparatus for evaluating the performance of a control system are disclosed. The method includes receiving data from the control system, wherein the data is received by a passive testing function, and calculating a parameter related to the performance of the control system using the passive testing function. The apparatus includes a processor operable to execute a passive testing function, wherein the passive testing function is configured to receive data from the control system and calculate a parameter related to the performance of the control system. The apparatus may also include an active testing function, wherein the active testing function is configured to provide a sequence of step changes to an input of the control system, receive data from the control system in response to the sequence of step changes, and calculate a parameter related to the performance of the control system.

Abstract: A system and method for controlling a controlled parameter that affects a target parameter of a target zone is disclosed. The method comprises providing a feedback control loop having a switching controller, a controlled device, and an averaging device. The controlled device comprises a time constant and a specified operational characteristic. The controlled device comprises a first operational state and a second operational state. The method further comprises calculating a time constant for the averaging device based at least on the time constant for the controlled device, and the specified operational characteristic. The specified operational characteristic may comprises a minimum amount of time that the controlled device operates before it can be switched between the first operational state and the second operational state.

Abstract: A facility management system includes a device which produces a change of an environmental characteristic in a building. A method for operating the device involves sensing the environmental characteristic to provide a measured value, and defining a desired maximum amplitude of variation within which the measured value may vary. A control signal is produced in response to the difference between the measured value and a desired value for the environmental characteristic. The control signal is then used to produce an output signal that turns the device on and off, wherein the output signal has a cycle period during which a pulse of a given duration occurs. The cycle period and the given duration are varied in response to the control signal without permitting the measured value to deviate more than desired.

Abstract: A method and apparatus of identifying a system is disclosed. The method comprises estimating at least one parameter in a second-order model of the system, and approximating at least one parameter in a first-order model of the system from the at least one second-order model parameter. The method may also comprise sampling an input to the system, sampling an output from the system. The apparatus comprises a device for estimating at least one parameter in a second-order model of the system, and device for approximating at least one parameter in a first-order model of the system from the at least one second-order model parameter.

Abstract: A method and system for controlling an environmental management system (e.g., an HVAC system) that controls an environmental parameter of a downstream controlled space (e.g., the temperature of a room in a building). The method includes providing a feedback control loop for controlling a controlled environmental parameter (e.g., the supply air temperature), and generating a feedback control signal based on the controlled parameter and a dynamic (e.g., a time constant) of the downstream controlled space. The system includes a device for receiving a signal representative of a measured value of a controlled parameter having a time constant that is smaller than the time constant of the downstream space. The system also comprises a filter, a device for producing a control signal representative of a deviation between a filtered value and a desired value of the controlled parameter, and a device for converting the control signal into a pulsed output signal that turns the device on and off.

Abstract: Disclosed is a method and apparatus for controlling multistage systems where the relative capacities (process gains) of each stage are known. The method uses a split-range control concept in order to control multiple stages with a single feedback controller, such as PID. Stage combinations are generated automatically and sequenced to provide contiguous control and optimum control resolution across the overall range of the multistage system. The control method incorporates hysteretic deadzones to improve robustness around stage transition points. The assumption of a tuned PI feedback controller allows the size of the deadzone to be related to general control performance requirements applicable across classes of similar systems. A simulated HVAC&R system is used to evaluate the method and it is compared an alternative approach.

Abstract: A facility management system includes a device which produces a change of an environmental characteristic in a building. A method for operating the device involves sensing the environmental characteristic to provide a measured value, and defining a desired maximum amplitude of variation within which the measured value may vary. A control signal is produced in response to the difference between the measured value and a desired value for the environmental characteristic. The control signal is then used to produce an output signal that turns the device on and off, wherein the output signal has a cycle period during which a pulse of a given duration occurs. The cycle period and the given duration are varied in response to the control signal without permitting the measured value to deviate more than desired.