摘要:
In a heating system containing twinned furnaces capable of independently operating at multiple levels, a method for providing multiple heating modes to satisfy a required heating load during a given cycle, there being some total number of heating modes, wherein each heating mode may be activated for a time interval whose length is a function of furnace activity during the most recent previous cycle. The method comprises the steps of: determining the existence of a heating load to be satisfied; operating both furnaces independently at levels appropriate to a first heating mode for a first time interval that does not exceed a first predetermined limit; for each subsequent heating mode up to a number of one less than the total number of heating modes, operating both furnaces independently at levels appropriate to each subsequent heating mode for a subsequent time interval that does not exceed a subsequent predetermined limit; and operating both furnaces independently at levels appropriate to a final heating mode for a final time interval until the heating load is satisfied; calculating a thermal load requirement, as a function of all of the time intervals; and predetermining all of the predetermined time intervals for a next cycle, from the calculated thermal load requirement.
摘要:
An adaptive furnace controller utilizing analog temperature sensing to maintain a constant preselected temperature in the heat exchanger during operation. The adaptive furnace control measuring heat exchanger temperature and regulating a controllable valve to adjust burner firing rate, thereby holding heat exchanger operating temperature constant. Further, creating constant on/off times based on the previous cycle on/off times of the furnace by regulating circulation blower speed. By increasing blower speeds to shorten "on" times or decreasing blower speeds to increase "on" times, and thereby achieving optimum cycle times.
摘要:
A system for detecting an at-fault combustor includes a sensor that is configured to sense combustion dynamics pressure data from the combustor and a computing device that is in electronic communication with the sensor and configured to receive the combustion dynamics pressure data from the sensor. The computing device is programmed to convert the combustion dynamics pressure data into a frequency spectrum, segment the frequency spectrum into a plurality of frequency intervals, extract a feature from the frequency spectrum, generate feature values for the feature within a corresponding frequency interval over a period of time, and to store the feature values to generate a historical database. The computing device is further programmed to execute a machine learning algorithm using the historical database of the feature values to train the computing device to recognize feature behavior that is indicative of an at-fault combustor.
摘要:
A multivariable control system for controlling boiler burners. The system includes burner actuators, boiler sensors, a control system coupled to the actuators and the sensors and further includes a memory and a processor, and an application stored in the memory. When executed by the processor, the application executes a multivariable control algorithm to determine actuator manipulated variable values to control in part the burners based on data received from the sensors and based on a plurality of gain values. The application also executes an adaptation algorithm to change an actuator manipulated variable value, to maintain the changed manipulated variable value for a pre-determined period of time, to determine a change in data received from the sensors, to determine a gain value based on the changed manipulated variable value and the change in data received from the sensors, and to provide the determined gain value to the multivariable control algorithm.
摘要:
A method for starting a combustion device, in particular after a first ignition failure, in particular for starting a gas burner under unknown basic conditions, wherein a characteristic diagram of a start air ratio depending on the burner temperature known from empirical analysis is stored for the combustion device in a memory, wherein a calibration of the starting process is performed, wherein the ratio of opening of the gas valve (w) to air volume mL necessary for ignition is iteratively determined by variation of the gas and/or air volume; and in case of ignition, the combustion device is started and the applicable air ratio (λ)IGNITION is stored.
摘要:
A multivariable control system for controlling boiler burners. The system comprises burner actuators, boiler sensors, a control system coupled to the actuators and the sensors and comprising a memory and a processor, and an application stored in the memory. When executed by the processor, the application executes a multivariable control algorithm to determine actuator manipulated variable values to control in part the burners based on data received from the sensors and based on a plurality of gain values. The application also executes an adaptation algorithm to change an actuator manipulated variable value, to maintain the changed manipulated variable value for a pre-determined period of time, to determine a change in data received from the sensors, to determine a gain value based on the changed manipulated variable value and the change in data received from the sensors, and to provide the determined gain value to the multivariable control algorithm.
摘要:
In a controlling device that uses a model for simulating characteristics of a control target to learn a method of generating a model input that satisfies a target model output value and generates an operation signal according to a learning result, a target model output value for satisfying an operation target value is determined from measured signals from the control target.The controlling device comprising: a model for predicting the value of a measured signal obtained when an operation signal is given to the control target, a function for learning a method of generating a model input so that a model output satisfies the target value, a function for determining an operation signal to be given to the control target according to the learning result, a database for storing measured signal limit values set in advance, an external input interface for fetching measured signals from the control target, a measured signal database for storing the values of the fetched measured signals, and a function for determining an initial value of the target model output value by using limit values of the measured signals and at least one of an average, a maximum value, or a minimum value that are calculated from the measured signals stored in the measured signal database.
摘要:
A gas turbine output learning circuit is configured to compute a current combustion gas temperature TIT at an inlet of a gas turbine by linear interpolation by use of two characteristic curves A and B respectively representing relations between a pressure ratio and an exhaust gas temperature in the cases of the combustion gas temperature at the inlet of the gas turbine at 1400° C. and 1500° C., then to compute ideal MW corresponding to this combustion gas temperature TIT at the inlet of the gas turbine by linear interpolation according to 1400° C.MW and 1500° C.MW (temperature controlled MW), and then to correct the 1400° C.MW and the 1500° C.MW so as to match the ideal MW with a measured gas turbine output (a power generator output).
摘要:
The control of emissions from fossil-fired boilers wherein an injection of substances above the primary combustion zone employs multi-layer feedforward artificial neural networks for modeling static nonlinear relationships between the distribution of injected substances into the upper region of the furnace and the emissions exiting the furnace. Multivariable nonlinear constrained optimization algorithms use the mathematical expressions from the artificial neural networks to provide the optimal substance distribution that minimizes emission levels for a given total substance injection rate. Based upon the optimal operating conditions from the optimization algorithms, the incremental substance cost per unit of emissions reduction, and the open-market price per unit of emissions reduction, the intelligent emissions controller allows for the determination of whether it is more cost-effective to achieve additional increments in emission reduction through the injection of additional substance or through the purchase of emission credits on the open market. This is of particular interest to fossil-fired electrical power plant operators. The intelligent emission controller is particularly adapted for determining the economical control of such pollutants as oxides of nitrogen (NOx) and carbon monoxide (CO) emitted by fossil-fired boilers by the selective introduction of multiple inputs of substances (such as natural gas, ammonia, oil, water-oil emulsion, coal-water slurry and/or urea, and combinations of these substances) above the primary combustion zone of fossil-fired boilers.
摘要:
A method, and a system for implementing the method, for detecting whether a flame is an on state or alternatively is in an off state. The method includes (i) detecting the flame and generating therefrom a flame signal capturing one or more attributes of the flame; (ii) using a high-order cumulant-to-moment formula to determine high-order cumulants for a random variable process representation of the flame signal; and (iii) determining whether the flame is on or off using the high-order cumulants. The method includes the step of applying the high-order cumulant-to-moment formula in a self-learning algorithm to determine flame-on high-order cumulants and flame-off high-order cumulants for the flame. Step (iii) includes comparing the high-order cumulants to the flame-on high-order cumulants and the flame-off high-order cumulants to determine whether the status of the flame is on or off.