154 results about "Time lag" patented technology

The invention relates to the technical field of data processing, in particular to a computer-aided air conditioner load prediction model simulation construction method, which comprises the following steps of: acquiring data of each environmental parameter in a building at all moments in each period in real time to form a monitoring sequence; the method comprises the following steps: performing analogue simulation on energy consumption of an air conditioner to obtain load data of an air conditioner load at all moments in each period, and forming a load sequence; acquiring a lagging time length; extracting a time delay subsequence of each environmental parameter in each period; the trend synchronization degree between each environment parameter and the air conditioner load in each period is determined; determining a coupling coefficient of any two environmental parameters in each period; determining a reference evaluation value between the current period and each of the rest periods; obtaining each reference period; and constructing a load prediction model. According to the method, prediction deviation caused by neglecting interaction influence and lag influence among various environmental parameters can be avoided, and the prediction accuracy of the air conditioner load is improved.

The invention relates to a multi-machine cooperative dynamic balance driving method, system and device for a spiral lifting machine, and the method comprises the steps: carrying out the compensation of the time lag of an actuator through employing a non-linear state observation and time lag compensation combined method, and obtaining a feedforward control quantity; performing Lyapunov stability feedback processing on the vibration acceleration signal to obtain a vibration suppression control quantity; designing a multi-section S-shaped speed curve, and calculating a closed-loop feedback control quantity by adopting PID (Proportion Integration Differentiation) combined with a robust control algorithm; and according to the feedforward control quantity, the vibration suppression control quantity and the closed-loop feedback control quantity, multi-machine cooperative dynamic balance driving of the spiral lifting machine is carried out. According to the invention, a non-linear state observation and time delay compensation technology is adopted, so that the synchronization error is reduced to a millisecond level; the low-frequency vibration amplitude is reduced through dynamic feedback control designed based on the Lyapunov theory; the hydraulic impact is obviously reduced by adopting a multi-section S-shaped speed curve; external disturbance is observed in real time through Kalman filtering, feed-forward compensation is carried out, and the robustness of the system is greatly enhanced.

The invention provides a self-adaptive fixed time tracking control method based on event triggering, which is used for solving the technical problem that a virtual control law is easy to generate singularity in the traditional backstepping method design. The method comprises the following steps: establishing a mathematical model of a non-strict feedback nonlinear system with input time delay, and introducing an auxiliary system to counteract delay influence; an error dynamic system is obtained through coordinate transformation; according to system fixed time convergence, designing a piecewise function, introducing a backstepping method to design a controller and an adaptive law, using an RBFNN to approach an unknown function therein, designing a virtual control signal corresponding to each error signal, and obtaining an actual controller and an adaptive law; according to the actual self-adaptive controller, event triggering conditions are designed, when the event triggering moment is reached, the event triggering conditions containing input are triggered, and information transmission and response are carried out. An event triggering mechanism is designed, the number of times of control instruction transmission is reduced, communication resources are saved, and rapid convergence and safe operation of the system state are achieved.

The invention discloses a periodic disturbance compensation method and device for an input time delay system, equipment and a medium, and relates to the field of disturbance control, and the method comprises the steps: obtaining a state-space equation of the input time delay system; according to the state-space equation of the input time-delay system, converting the input time-delay system into a non-input time-delay system by adopting a time-delay compensation method; based on the error signal of the no-input time delay system, estimating the value of the to-be-determined parameter by adopting an internal model principle and a linear regression method to obtain an estimated value of the to-be-determined parameter; and determining a control input signal of the zero-input time-delay system by adopting the feedback controller according to an output signal of the zero-input time-delay system and the to-be-determined parameter estimation value so as to perform periodic disturbance compensation on the zero-input time-delay system. The feedback controller is adopted to perform feedback control on the control input signal according to the output signal of the system, and compensation of unknown time-varying periodic disturbance of the input time delay system can be realized.

The invention discloses a thermal working time lag process ADRC design method with time lag robustness. The thermal working time lag process ADRC design method comprises the steps that 1, a transfer function model of a first-order inertia time lag process of a thermal process is established; step 2, establishing a time-delay ADRC structure based on model information driving; 3, obtaining a proportional gain with expected closed-loop dynamic representation and a corresponding observer bandwidth setting rule through low-frequency approximation; step 4, scaling control parameters of the ADRC system according to the transfer function model established in the step 1, and setting default adjustment parameters of proportional gain and observation bandwidth; 5, carrying out equivalent two-degree-of-freedom conversion on the closed-loop system, analyzing the nominal stability of the ADRC system based on a double-track method, and obtaining a nominal stability domain of the control parameters; and step 6, in the nominal stability domain obtained in the step 4, according to the regularization rule of the ADRC scaling parameter and the demand of comprehensive robustness, obtaining the time constant of the low-pass filter in the compensation channel by establishing a monotonically decreasing amplitude curve of the time-delay ADRC open-loop Bode diagram.

The invention discloses an integral time-delay parameter identification method based on unbalance, which comprises the following steps: S1, constructing a discrete table of a river water level-storage capacity relationship in a steady state based on a river and canal hydrodynamic model, and constructing a river water level-storage capacity relationship model by adopting a three-dimensional spline interpolation method; s2, calculating the actual average storage capacity variation of the river channel in each unit time length according to the river channel water level-storage capacity relation model; s3, combining the flow monitoring data at the two ends of the riverway with the actual average storage capacity variation of the riverway in each unit time length, and calculating the unbalance of the riverway; and S4, constructing an integral time-delay model according to the unbalance of the river channel, and identifying parameters in the integral time-delay model by adopting a genetic algorithm. Based on an introduction mechanism of the unbalance, the difference between the theoretical water volume change and the actual observation change is explicitly described; therefore, the problem that a traditional integral time-delay model neglects non-ideal factors such as system lag and measurement errors is effectively solved.

The invention discloses a non-linear state rapid fitting method for an aircraft, and belongs to the field of aircraft control. The implementation method comprises the following steps: constructing a two-loop attitude pilot and a three-loop attitude pilot, and discretizing to obtain a guidance instruction with a time-delay effect; according to coordinate conversion, forward deriving each aerodynamic parameter of the aircraft and an aircraft overload instruction equation; the method comprises the following steps: calculating all pneumatic data according to part of pneumatic data obtained by a blowing experiment of an aircraft, and fitting a guidance instruction with a balance attack angle, a sideslip angle and a rudder deflection angle of the aircraft to obtain a corresponding interpolation table; all aerodynamic parameters in the flight process of the aircraft are obtained according to an aircraft guidance instruction and an interpolation table in the actual situation, namely, nonlinear state rapid fitting of the aircraft is achieved, and simulation reproduction of the aircraft as a mass point in the whole guidance process is achieved according to the nonlinear state rapid fitting result. And the precision and efficiency of aircraft guidance control are improved.

To provide a program production system that measures a delay time of a video image with respect to audio and auxiliary data by a simple method so as to realize synchronization among the video image, the audio and the auxiliary data generated at the same time.SOLUTION: The video time difference calculating unit 11 - 1 of the video delay measuring apparatus 2 extracts the time stamp V1 from the video RTP packet VTS1 and generates the video RTP packet V2 including the timing information. The video RTP packet V2 is transmitted to the video delay time difference measuring path. A video time difference calculation section 11-1 extracts a time stamp V3 from a video RTP packet VTS2 to obtain a video time difference VT. The audio time difference calculator 11-2 obtains the audio time difference ST, and the ancillary data time difference calculator 11 - 3 obtains the ancillary data time difference AT. The delay time calculating unit 13 subtracts the audio time difference ST from the video time difference VT to obtain the audio delay time SD, and subtracts the ancillary data time difference AT from the video time difference VT to obtain the ancillary data delay time AD.SELECTED DRAWING: Figure 5

The invention discloses a high-order multi-agent system control method with unknown input time lag and quantization, which comprises the following steps: S1) under the condition of unknown time-varying time lag and input quantization, carrying out system description on an uncertain high-order multi-agent system and introducing a lag uniform quantizer; s2) converting an uncertain high-order multi-agent system tracking control problem with unknown time-varying time-lag and input quantization into a bounded problem of a differential equation solution with time-lag; s3) constructing a dominant expression of the system and feasibility conditions for realizing bounded tracking according to the bounded problem of the time delay differential equation; and S4) performing control design according to a dominant expression of the system and bounded tracking feasibility conditions. The invention designs an adaptive finite time dynamic surface control scheme for a high-order multi-agent system with unknown input delay. Meanwhile, the finite time stability theorem is utilized to prove that all signals in the closed-loop system are semi-globally practical and stable in finite time.

The invention discloses a cascade control method of an impulse turbine regulating system based on an improved crown porcupine algorithm, which considers mechanical time lag of a hydraulic actuating mechanism and establishes a mathematical model of the impulse turbine regulating system under small fluctuation. According to the DMC-FOPID cascade control method for the impulse turbine regulating system, FOPID control is adopted as inner loop control, DMC (dynamic matrix control) is introduced as outer loop control, and the DMC-FOPID cascade control method for the impulse turbine regulating system is provided. According to the method, a Created Porcupine Optimization (CPO) algorithm is improved in combination with tent chaotic mapping and a fractional order longhorn beetle search mechanism, and the improved ICPO algorithm is provided, so that the optimization performance of the CPO is improved, and therefore, the optimal performance of the CPO is improved, and the optimal performance of the Created Porcupine Optimization (ICPO) is improved, and the optimal performance of the Created Porcupine Optimization (ICPO) is improved, and the optimal performance of the Created Porcupine Optimization (ICPO) is improved. And FOPID parameters are set and optimized through ICPO, and control simulation is carried out based on Simulink. The result shows that the cascade control method can effectively improve the control performance of the impulse turbine adjusting system.

The invention discloses a short-term load prediction method and system considering multi-scale time-lag correlation. The method comprises the following steps: constructing time sequence data of a load and a comprehensive meteorological index; respectively decomposing the time sequence data of the load and the comprehensive meteorological index through an empirical mode decomposition derivation method; dividing each load scale component and each comprehensive meteorological index scale component into a plurality of analysis mode groups, and respectively analyzing the first overall dynamic correlation; based on the second overall dynamic correlation, correcting the time delay between the two components in the analysis mode group in which the first overall dynamic correlation is smaller than a set dynamic correlation threshold value; training the load prediction model by adopting each analysis mode group; and obtaining a short-term load prediction final result in real time through the trained load prediction model. According to the method, the time lead / lag relationship between the load and the multivariate data is corrected, the dynamic analysis capability of the multivariate data in different change periods is enhanced, and the accuracy of load prediction is improved.

The system according to this embodiment aims to eliminate the time lag between offline and online operations through logistics optimization and demand forecasting. [Solution] The system according to the embodiment comprises a logistics analysis unit, a delivery route selection unit, a demand forecasting unit, an inventory management unit, and a recommendation unit. The logistics analysis unit analyzes each process of logistics. The delivery route selection unit selects a delivery route based on the information analyzed by the logistics analysis unit. The demand forecasting unit analyzes the user's purchase history or behavioral data. The inventory management unit manages inventory based on the forecast results obtained by the demand forecasting unit. The recommendation unit analyzes the user's behavioral data and suggests products.

The invention discloses an island micro-grid load frequency stability control method considering communication time lag and a virtual inertia link, and the method comprises the steps: firstly building an island micro-grid load frequency control model containing the virtual inertia link, then constructing a Lyapunov functional on the basis, carrying out the derivation of the constructed functional, and carrying out the calculation of the load frequency stability of the island micro-grid. Derivative integral terms are defined by means of a generalized free-weight integral inequality, then a time-delay correlation stability criterion based on a linear matrix inequality is obtained, then the linear matrix inequality under different PI parameter conditions is solved, a maximum allowable time-delay upper limit (MDSM) for ensuring system stability is obtained, the time-delay upper limit is improved, system conservative property is reduced, and the stability of the system is improved. On the basis of the prior art, the robustness of the system is further improved, and the system has a larger stable operation area.

The invention belongs to the technical field of intelligent control, and particularly relates to an intelligent digital dosing method and system based on edge computing, and the method comprises the following steps: calculating a system dynamic inertia period representing the comprehensive time lag of a dosing process through the pipeline volume, the real-time flow velocity and the reference reaction time, and calculating the pH value of the dosing process according to the inertia period and the real-time change rate of the pH value. The static deviation between the pH value and the target set value is corrected to obtain a prospective state deviation, a dynamic control gain modulation factor is calculated through a nonlinear mapping function, the dynamic control gain modulation factor is applied to a feedback control algorithm, and the accurate control quantity of the digital dosing pump is generated and driven. According to the invention, oscillation in the control process is inhibited, and the stability of the system, the dosing accuracy and the self-adaptive ability to the change of working conditions are remarkably improved.

The application provides a multi-dimensional diagnosis method for seepage state of porous media based on dynamic evolution of lag time, and belongs to the field of dam safety monitoring; solves the problems of strong hysteresis, many interferences and poor applicability of existing dam seepage monitoring; the method comprises the following steps: obtaining long sequence reservoir water level and piezometric tube water head monitoring data of a target porous medium and preprocessing; calculating the reference memory duration of the lag response of the piezometric tube water head to the reservoir water level fluctuation, and establishing a normal state baseline; extracting a dynamic lag time sequence; calculating the scaling index sequence of each piezometric tube water level sequence as a memory persistence index; calculating the transfer entropy of the reservoir water level to the piezometric tube water head as a hydraulic information transmission strength index; establishing a reservoir water level-lag response time function in a reference period, stripping the geometric effect, extracting the net medium effect, establishing a multi-dimensional joint criterion, determining the seepage state of the target porous medium and dividing the degradation grade; and the application is applied to dam seepage diagnosis.

The present application belongs to the technical field of power system, and particularly relates to a time-delay power system stability analysis method and system. The method firstly establishes a load frequency control system model including time delay and nonlinear load disturbance, wherein the nonlinear load disturbance is a nonlinear disturbance taking unknown exogenous load disturbance as current and delayed state variable; then an augmented Lyapunov-Krasovskii functional is constructed, and an analysis method based on time-delay dependent matrix free matrix integral inequality and anti-convex combination inequality is adopted to analyze the stability of the load frequency control system, so as to obtain the stability criterion of the load frequency control system. The present application plays an important role in improving the calculation accuracy and time delay upper limit, and is helpful to expand the stable operation area of the power system.

This invention aims to optimize the input sequence of actuators with significant time delays in marine vehicles (such as variable buoyancy hydraulic pumps and valves, and slow-response actuators like rudders). Under complex sea conditions and model uncertainties, this method achieves rapid and stable attainment of the target operational state with minimal action cost, while simultaneously satisfying safety and lifespan constraints. The method disclosed in this invention uses a parameter identification model as the prediction kernel, incorporating terminal task deviation, the number of execution actions and non-zero duration, and the safety volume boundary into a multi-objective cost function. It employs an improved LM algorithm with adaptive damping for sequence-level optimization and rolling updates, thereby overcoming the shortcomings of conventional closed-loop compensation and pure gradient methods in terms of slow convergence, oscillation, and difficulty in balancing safety and wear on time-delayed objects. This significantly improves convergence speed, control accuracy, and reliability, while reducing energy consumption and mechanical wear.

The application relates to the technical field of ring network cabinets, and discloses a ring network cabinet intelligent monitoring and self-recovery control method and system based on edge computing, which comprises the following steps: collecting voltage data, current data and environmental temperature data on the edge side; when the voltage data or the current data changes in value, a time delay compensation observation window is established; the voltage data, the current data and the environmental temperature data are matched and verified to determine whether a synchronization constraint condition is met; when it is determined that the synchronization constraint condition is not met, the environmental temperature data is time-series shifted based on a time difference value; when it is determined that the synchronization constraint condition is met, the environmental temperature data is time-series shifted based on a time delay coefficient; synchronized sensing data is obtained, and a self-recovery control instruction is generated; and the time difference value is integrated into a historical time delay sequence, and the time delay coefficient is updated. The application reflects the real lag characteristics of environmental quantities on electrical changes, and improves the reliability of operation state judgment.

The application discloses a kind of active suspension system model parameter adaptive calibration test bench test method and system, belong to vehicle active suspension test technical field, sensitive system parameters are filtered out by sensitivity analysis function, then sensitive system parameters are identified and calibrated, greatly reduce the amount of calculation in calibration process, improve the test implementation efficiency;Through time delay boundary calculation, the time delay feedback coefficient and time delay are optimized, the optimal time delay feedback coefficient and optimal time delay are obtained, and through adaptive adjustment, time delay compensation calibration is carried out using Smith prediction compensation model, which significantly improves the adaptive ability and compensation accuracy of time-varying time delay;In addition, standard test signals are applied to the target active suspension test bench test system, and time domain response data are collected to determine the tolerance according to the time domain response data to complete the parameter adaptive calibration of the active suspension system dynamics model.

The application discloses a stability analysis method of a load frequency control system considering participation of an electric vehicle, constructs a new Lyapunov functional based on a time delay interval, establishes different sub-functionals in different time delay intervals, and integrates a time delay product type item to capture more time delay information; and then by combining the proposed functional with a zero equation method, the application discards a mode of using a single and fixed functional in the whole time delay interval in the traditional way, reduces the conservativeness of a criterion, and obtains a maximum time delay margin, so as to provide less conservative stability analysis and control design basis for the load frequency control system containing the electric vehicle.

The invention discloses a steer-by-wire automobile stability control method, device and equipment considering time delay. The method comprises the steps that a steer-by-wire system model is established; establishing a non-linear time delay model existing in steer-by-wire; based on the steer-by-wire system model, performing linearization processing on the nonlinear time lag model to obtain a transfer function of a steer-by-wire actuating mechanism containing time lag; and based on the transfer function of the steer-by-wire executing mechanism containing the time delay, stability control is conducted on the automobile. Therefore, aiming at the delay problem existing in a steer-by-wire system, compared with passive control based on a wave variable theory and a dissipation theory, the operability is reduced, and the tracking precision cannot be ensured; according to the method, on the premise that the robust stability of the system is guaranteed, the tracking capacity, the anti-interference capacity and the like of the system under the condition of random delay can be guaranteed at the same time.

An image pickup apparatus capable of suppressing a time lag until photographing is provided. The image pickup apparatus includes an image sensor including a plurality of pixels, and at least one processor or circuit and a memory storing instructions to cause the at least one processor or circuit to perform operations of a setting unit that sets first photographing conditions in accordance with user's instructions, a detecting unit that detects a characteristic region based on pixel information obtained from the plurality of pixels, and a control unit that causes pixels in the characteristic region among the plurality of pixels to be photographed under second photographing conditions different from the first photographing conditions, and causes pixels in another region other than the characteristic region among the plurality of pixels to be photographed under the first photographing conditions. The detecting unit and the control unit are provided inside of the image sensor.

This invention discloses a method for evaluating inter-well connectivity based on dynamic differential pressure and time-delay scanning, comprising the following steps: S1: acquiring dynamic monitoring data of the target well group; S2: performing time alignment and unified time-scale resampling on the dynamic monitoring data to obtain an analysis time-series data table; S3: constructing a dynamic response characteristic sequence of production wells; S4: smoothing to obtain a smoothed injection volume sequence of injection wells and a smoothed dynamic response characteristic sequence of production wells; S5: progressively time-shifting the smoothed injection volume sequence of injection wells to obtain a time-delay correlation coefficient sequence under different lag times τ; S6: evaluating the inter-well connectivity strength based on the maximum correlation coefficient and evaluating the inter-well conduction speed based on the optimal lag time. This invention can reduce the impact of fluctuations in the operating conditions of production wells on the inter-well connectivity identification results, improve the stability, accuracy, and engineering applicability of inter-well connectivity evaluation, and provide technical support for the dynamic monitoring and connectivity evaluation of injection-production well groups.

The application relates to a dam displacement prediction method considering time lag characteristics, comprising the following steps: obtaining displacement observation data of a target dam and preprocessing the displacement observation data to form a displacement observation sequence and determine an upper limit of time lag in the displacement observation sequence; constructing a displacement prediction data set of the target dam based on the displacement observation sequence and environmental variable factors affecting the displacement of the dam, and time-paneling data in the displacement prediction data set according to the upper limit of time lag; constructing a deep neural network based on a gated recurrent unit, and establishing a time lag parameter considering the upper limit of time lag; traversing the time lag parameter, and selecting an optimal time lag parameter; training the deep neural network based on the gated recurrent unit by using the time-panelized displacement prediction data set according to the optimal time lag parameter, so as to obtain a trained dam displacement prediction model; and using the trained dam displacement prediction model to predict the displacement of the target dam.

The present invention discloses a method for the revival of rivers and lakes based on the dynamic change process and time-delay effect of the ecosystem. It includes the following steps: Step 1: Determine the revival goals of rivers and lakes; Step 2: Determine the lag time of ecosystem response; Step 3: Determine the revival plan for rivers and lakes. The present invention first proposes a method for the revival of rivers and lakes based on the dynamic change process and time-delay effect of the ecosystem. By considering the historical change process and current situation of the ecosystem, different levels of revival goals, namely low, medium, and high levels, are determined, improving the scientificity and reliability of the revival of rivers and lakes; through the lag correlation between the ecosystem status and external driving pressure, the time when the ecosystem response lags behind the driving pressure is scientifically determined; by establishing the relationship between the ecosystem status and driving pressure based on the time-delay effect, the regulation intensity of the driving pressure under different levels of revival goals is proposed, and it is determined whether to adopt artificial or natural restoration means, improving the success rate of the revival of rivers and lakes and avoiding over-restoration.

The invention discloses a cascade hydropower station double-time-lag incoming water prediction method, system and device and a medium, and the method comprises the steps: obtaining cascade drainage basin data, constructing a probability distribution model of meteorological variables according to the cascade drainage basin data, and generating a meteorological uncertainty scene; the method comprises the following steps: constructing a double-time-delay convolution prediction model according to hydrological characteristics of a cascade hydropower station, and parameterizing and training the double-time-delay convolution prediction model by adopting a data driving method to obtain a first double-time-delay convolution prediction model; and taking the meteorological uncertainty scene as input of a first double-time-lag convolution prediction model, performing simulation prediction on multiple scenes of natural inflow components, outputting natural inflow evolution processes of all power stations in the corresponding meteorological scene, and realizing cascade hydropower station double-time-lag inflow prediction. And a scientific basis is provided for dispatchers to cope with different risk scenes.

The invention provides an airport apron queue length prediction method based on a multi-queue network model. Firstly, fluid flow approximation serves as a theoretical basis, queues are divided according to control seats and sliding directions, sliding time lag is expressed through a delay differential equation, a flow transfer rule is described by means of a Jackson routing matrix, and a single-queue model is expanded to a multi-queue network. Meanwhile, parameters such as service rate and delay are calibrated based on historical data. By means of the method, the multi-stage congestion form of the airport apron peak period is accurately represented, minute-level all-day prediction is achieved, the expressivity and usability of the method in the airport apron scene are verified, the airport ground operation toughness can be improved, and a new modeling thought is provided for hub airport airport apron operation optimization.

An elevator door device is provided that can detect a position that serves as a reference for the absolute position of a door while suppressing the occurrence of a detection time lag, without using a dedicated device for detecting the absolute position of the door. [Solution] The elevator door system includes a motor, a rotation angle sensor, a speed command unit that outputs a rotation speed command value for the motor, a speed control unit that calculates a torque command value so that the motor's rotation speed matches the rotation speed command value, a door position detection unit that detects the door position based on the rotation angle, and a load torque application unit that applies a mechanical load torque to the motor when the door passes a preset reference position between the fully open position and the fully closed position during opening / closing. The door position detection unit identifies a reference rotation angle, which is the rotation angle when the door is in the reference position, based on changes in the torque command value corresponding to the load torque, and detects the absolute position of the door based on the identified reference rotation angle and the rotation angle.

To provide a pallet carrying in / out device capable of adjusting positional deviation of a stop position of left and right movable frames with a simple structure.SOLUTION: Each of load carrying in / out mechanisms of a pallet carrying in / out device comprises movable frames 21L, 21R, and a movable frame moving mechanism 5 for advancing / retracting the movable frame with respect to a working area S. The movable frame moving mechanism 5 includes: a pair of stoppers 55A, 55B; a pair of abutting parts 56A, 56B; a main sensor 86 for detecting that the movable frame moving mechanism 5 and a first abutting part abut on the stopper; and a control device 100 for selectively executing a first stop control for stopping a drive mechanism 8 by causing time lag between detection timing of the main sensor and stop timing of the drive mechanism 8, and a second stop control for stopping the drive mechanism without causing time lag.SELECTED DRAWING: Figure 18

To reduce a time lag from an instruction to start moving image recording to the start of the moving image recording, in an imaging system in which a control body of a diaphragm can be switched.SOLUTION: An imaging system 1 has: a diaphragm driving ring 208 that sets a first diaphragm value according to a user operation to a diaphragm 202; a lens control unit 205 that performs drive control of the diaphragm 202; and a camera control unit 104 that sets a second diaphragm value to the diaphragm 202 on the basis of a photometric value, and controls the drive of the diaphragm 202 through the lens control unit 205. When switching from an automatic diaphragm mode in which the camera control unit 104 performs drive control of the diaphragm 202 to the second diaphragm value through the lens control unit 205, to a manual diaphragm mode in which the lens control unit 205 performs drive control of the diaphragm 202 to the first diaphragm value, the camera control unit 104 switches a control body of the diaphragm 202 to the lens control unit 205 after performing drive control of the diaphragm 202 to the first diaphragm value.SELECTED DRAWING: Figure 7