Abstract: A method includes receiving samples of one or more monitored variables relating to building equipment, updating a statistical metric of the samples, determining whether the building equipment is operating in a steady state or operating in a transient state using the statistical metric of the samples, and adjusting an operation that uses the samples as an input based on whether the building equipment is operating in the steady state or operating in the transient state.

Abstract: A method of controlling signal transmission in a building control system including measuring a number of signal values associated with an environmental variable using a sensor of a wireless device, dynamically determining, by the wireless device, a noise threshold based on the number of signal values, combining a first signal value and a second signal value of the number of signal values using a mathematical relationship to determine a result associated with the first signal value and the second signal value, and periodically transmitting the first signal value from the wireless measurement device to a controller in response to the result exceeding the noise threshold.

Abstract: A method for performing extremum-seeking control of a plant includes determining multiple values of a correlation coefficient that relates a control input provided as an input to the plant to a performance variable that characterizes a performance of the plant in response to the control input. The performance variable includes a noise-free portion and an amount of noise. The method includes determining an adjusted correlation coefficient by scaling a first value of the correlation coefficient selected from the multiple values relative to a second value of the correlation coefficient selected from the multiple values. The adjusted correlation coefficient relates the noise-free portion of the performance variable to the control input. The method includes using the adjusted correlation coefficient to modulate the control input provided as an input to the plant.

Abstract: A temperature control system. The control system includes a flow sensor configured to monitor water flow through a valve, an actuator coupled to the valve, and a first controller configured to establish a setpoint for a second controller. The second controller monitors fluid flow through the valve and combines a weighted first command from the first controller and a weighted second command from the second controller to generate a control signal, wherein combining the weighted first command and the weighted second command is based on the reliability of the flow sensor. The second controller further controls the actuator based on the control signal.

Abstract: A method of controlling signal transmission in a building control system including measuring a number of signal values associated with an environmental variable using a sensor of a wireless device, dynamically determining, by the wireless device, a noise threshold based on the number of signal values, combining a first signal value and a second signal value of the number of signal values using a mathematical relationship to determine a result associated with the first signal value and the second signal value, and periodically transmitting the first signal value from the wireless measurement device to a controller in response to the result exceeding the noise threshold.

Abstract: A self-perturbing extremum-seeking controller for a plant that includes at least a static portion includes a processing circuit. The processing circuit is configured to obtain a value of a performance variable characterizing a performance of the plant. The processing circuit is configured to determine a sign of a gradient of the performance variable with respect to an input to the static portion of the plant. The processing circuit is configured to adjust a control input for the plant using the sign of the gradient, and provide the control input to the plant to affect the performance variable.

Abstract: An extremum seeking controller includes a processing circuit configured to modulate a manipulated variable provided as an input to a plant using an extremum-seeking control technique to drive a gradient of an objective function with respect to the manipulated variable toward an extremum. The objective function includes a performance variable characterizing a performance of the plant responsive to the manipulated variable. The objective function also includes a saturation adjustment term that becomes active as the plant approaches a saturation point and remains active as the plant operates within a saturated region past the saturation point. The saturation adjustment term causes the processing circuit to adjust the manipulated variable toward a value of the manipulated variable that returns the plant from the saturated region to a non-saturated region.

Abstract: A method includes receiving samples of one or more monitored variables relating to building equipment, updating a statistical metric of the samples, determining whether the building equipment is operating in a steady state or operating in a transient state using the statistical metric of the samples, and adjusting an operation that uses the samples as an input based on whether the building equipment is operating in the steady state or operating in the transient state.

Abstract: A pressure disturbance rejection valve assembly is provided. The valve assembly includes a valve, a flow rate sensor, and an actuator. The actuator includes a motor, a drive device configured to be driven by the motor and coupled to the valve for driving the valve within a range of positions, and a position sensor configured to measure a rotational position of the drive device. The actuator further includes a communications mechanism configured to receive a flow rate setpoint and a processing circuit. The processing circuit is configured to determine an actuator position setpoint using a feedback control mechanism based on the flow rate setpoint and the flow rate measurement, operate the motor to drive the drive device to the actuator position setpoint, detect a fault condition based at least in part on the rotational position measurement or the flow rate measurement, and perform a fault mitigation action in response to detection of the fault condition.

Abstract: A controller for HVAC equipment of a plant includes a processing circuit configured to predict an impact of a time delay of the plant on a performance variable received as feedback from the plant. The processing circuit is configured to artificially increase or decrease a value of the performance variable using an adjustable time delay parameter to at least partially negate the impact of the time delay on the performance variable. The processing circuit is configured to use the artificially increased or decreased value of the performance variable in on-off feedback control to operate the HVAC equipment.

Abstract: A building management system includes connected equipment and a predictive diagnostics system. The connected equipment is configured to measure a plurality of monitored variables. The predictive diagnostics system includes a communications interface, a steady state detector, a controller. The communications interface is configured to receive samples of the monitored variables from the connected equipment. The steady state detector is configured to recursively update a mean and a variance of the samples each time a new sample is received, identify whether each of the samples reflects a steady state or a transient state of operation of the connected equipment using the mean and the variance, and associate each of the samples to the steady state or the transient state as identified. The controller is configured to adjust an operation of the connected equipment based on the steady state or the transient state as identified.

Abstract: An on-off control system includes on-off equipment configured to operate in either an on state or an off state, an on-off controller configured to cause the equipment to transition between the on state and the off state based on a setpoint value and a deadband value to drive a control variable toward the setpoint value, and a deadband controller, according to some embodiments. In some embodiments, the deadband controller is configured to generate the deadband value used by the on-off controller. In some embodiments, the deadband controller is configured to generate the deadband value by obtaining a cost function that defines a cost based on at least a set of control values and the deadband value and selecting the deadband value that results in an optimal value of the cost function over a range of possible deadband values, the selected deadband value defining an optimal deadband value.

Abstract: An extremum seeking controller includes a processing circuit configured to modulate a manipulated variable provided as an input to a plant using an extremum-seeking control technique to drive a gradient of an objective function with respect to the manipulated variable toward an extremum. The objective function includes a performance variable characterizing a performance of the plant responsive to the manipulated variable. The objective function also includes a saturation adjustment term that becomes active as the plant approaches a saturation point and remains active as the plant operates within a saturated region past the saturation point. The saturation adjustment term causes the processing circuit to adjust the manipulated variable toward a value of the manipulated variable that returns the plant from the saturated region to a non-saturated region.

Abstract: A temperature control system. The control system includes a flow sensor configured to monitor water flow through a valve, an actuator coupled to the valve, and a first controller configured to establish a setpoint for a second controller. The second controller monitors fluid flow through the valve and combines a weighted first command from the first controller and a weighted second command from the second controller to generate a control signal, wherein combining the weighted first command and the weighted second command is based on the reliability of the flow sensor. The second controller further controls the actuator based on the control signal.

Abstract: A self-perturbing extremum-seeking controller for a plant that includes at least a static portion includes a processing circuit. The processing circuit is configured to obtain a value of a performance variable characterizing a performance of the plant. The processing circuit is configured to determine a sign of a gradient of the performance variable with respect to an input to the static portion of the plant. The processing circuit is configured to adjust a control input for the plant using the sign of the gradient, and provide the control input to the plant to affect the performance variable.

Abstract: A method of controlling signal transmission in a building control system including measuring a number of signal values associated with an environmental variable using a sensor of a wireless device, dynamically determining, by the wireless device, a noise threshold based on the number of signal values, combining a first signal value and a second signal value of the number of signal values using a mathematical relationship to determine a result associated with the first signal value and the second signal value, and periodically transmitting the first signal value from the wireless measurement device to a controller in response to the result exceeding the noise threshold.

Abstract: An asynchronous wireless data transmission system includes a wireless sensor and a data recipient device. The wireless sensor includes a measurement device configured to collect a plurality of samples of a measured variable at a plurality of different sampling times, a transmission generator configured to generate a compressed data object containing the plurality of samples of the measured variable, and a wireless radio configured to transmit the compressed data object at a transmission time asynchronous with at least one of the sampling times. The data recipient device includes an object decompressor configured to extract the plurality of samples of the measured variable from the compressed data object.

Abstract: A system for monitoring and controlling flow rate of a fluid through a valve, the system including a flow rate sensor configured to measure the flow rate of the fluid through the valve, and a controller in communication with the flow rate sensor. The controller is configured to receive the measured flow rate from the flow rate sensor and determine if the measured flow rate is equal to a predetermined flow rate value. In response to determining equality, the controller is configured to determine a minimum valve position threshold (xmin), and determine a minimum flow rate threshold (ymin) corresponding to xmin. The controller is further configured to calculate a corrected flow rate (?f) using xmin, ymin, and an indication of valve position (v). Additionally, the controller is configured to control a valve operation using the corrected flow rate (?f).

Abstract: A thermostat for a conditioned space includes a sensor that measures a value of a performance variable of the conditioned space, a user interface that receives a setpoint value from a user and displays information to the user, and a controller. The controller receives values of the performance variable from the sensor over a time period, stores the values of the performance variable, receives the setpoint value from the user interface, and determines a value of a manipulated variable based on the setpoint value and the values of the performance variable. The controller is configured to adjust an operation of HVAC equipment that affect the conditioned space based on the value of the manipulated variable. The controller is configured to determine a smoothed value of the performance variable based on the values of the performance variable and cause the user interface to display the smoothed value.

Abstract: A building management system includes building equipment configured to operate in accordance with an input to alter a variable state or condition of a building as a process function of the input while incurring a cost of operating the equipment as a cost function of the input. The building management system also includes a controller configured to calculate a value of a self-optimizing control variable as a function of a measured state of the building equipment and drive the value of the self-optimizing control variable towards a setpoint value by generating the input based on the self-optimizing control variable and providing the input to the building equipment. The function comprises multiplying the measured state by a matrix and adding an offset vector. Values of elements of the matrix and the offset vector are determined using a non-optimal reference.