• Title/Summary/Keyword: Integral control

Search Result 1,248, Processing Time 0.043 seconds

Extended Integral Control with the PI Controller (확장적분 제어개념을 도입한 PI 제어기에 관한 연구)

  • Ryu, Heon-Su;Jeong, Gi-Yeong;Song, Gyeong-Bin;Mun, Yeong-Hyeon
    • The Transactions of the Korean Institute of Electrical Engineers A
    • /
    • v.49 no.7
    • /
    • pp.345-349
    • /
    • 2000
  • This paper presents an extended integral control with the PI controller by introducing the delay and decaying factors. The extended integral control scheme is developed by substituting the proportional convolution integral control for the PI(Proportional Integral) control. So far, the integral part of PI controller produces a signal that is proportional to the time integral of the input signal to the controller. The steady-state operation points are affected forever by errors in the past due to the input signal containing the information of the error in the past. These phenomena may cause some disturbances for other control purposes related to the given PI control. Introduction of forgetting factors to the error in the past can resolve the disturbance problems. Various forgetting factors are developed using the delay elements, the decaying factors, and the combination of the delay and decaying factors. The proposed various extended integral control schemes can be applicable to the corresponding PI control designs in which the error in the past may badly affect the current steady-state operation points and may cause some disturbances for other control purposes.

  • PDF

Comparison of Proportional, Integral, and P-I Control Systems in Biological Wastewater Treatment Plants (생물학적 하수처리시스템에 적용된 Proportional, Integral 및 P-I 조절 시스템에 대한 비교)

  • Kim, Sungpyo
    • Journal of Korean Society on Water Environment
    • /
    • v.21 no.4
    • /
    • pp.410-415
    • /
    • 2005
  • The main purpose of this study is to evaluate the characteristics of three sets of traditional control methods (proportional, integral, and proportional - integral controls) through lab-scale biological reactor experiments. An increase in proportional gain ($K_c$) resulted in reduced dissolved oxygen (DO) offset under proportional control. An increase in integral time ($T_i$) resulted in a slower response in DO concentration with less oscillation, but took longer to get to the set point. P-I control showed more stable and efficient control of DO and airflow rates compared to either proportional control or integral control. Developed P-I control system was successfully applied to lab-scale Sequencing Batch Reactor (SBR) for treating industrial wastewater with high organic strength.

Extended Integral Control with the PID Controller (PID 제어기를 이용한 확장 적분 제어)

  • Moon, Young-Hyun;Jung, Ki-Young;Ryu, Heon-Su;Song, Kyung-Bin
    • Proceedings of the KIEE Conference
    • /
    • 1999.07c
    • /
    • pp.1063-1066
    • /
    • 1999
  • This paper presents an extended integral control with the PID controller by introducing the delay and decaying factors. The convolution integral control scheme is developed by substituting proportional convolution integral controls for the proportional-integral control. So far, the integral part of the PI controller produces a signal that is proportional to the time integral of the input of the controller. The steady-state operation points are affected forever by the errors in the past due to the input signal containing the information of the errors in the past. These phenomina may cause some disturbances for other control purposes related to the given PI control. Introduction of forgetting factors of the error in the past can resolve the disturbance problems. Various forgetting factors are developed using the delay, the decaying factors, and the combination of the delay and the decaying factors. The proposed various extended integral control schemes can be applicable to corresponding PI control designs in which the error in the past may badly affect to the current steady-state operation points and may cause some disturbances for other control purposes.

  • PDF

Optimization of PI Controller Gain for Simplified Vector Control on PMSM Using Genetic Algorithm

  • Jeong, Seok-Kwon;Wibowo, Wahyu Kunto
    • Journal of Power System Engineering
    • /
    • v.17 no.5
    • /
    • pp.86-93
    • /
    • 2013
  • This paper proposes the used of genetic algorithm for optimizing PI controller and describes the dynamic modeling simulation for the permanent magnet synchronous motor driven by simplified vector control with the aid of MATLAB-Simulink environment. Furthermore, three kinds of error criterion minimization, integral absolute error, integral square error, and integral time absolute error, are used as objective function in the genetic algorithm. The modeling procedures and simulation results are described and presented in this paper. Computer simulation results indicate that the genetic algorithm was able to optimize the PI controller and gives good control performance of the system. Moreover, simplified vector control on permanent magnet synchronous motor does not need to regulate the direct axis component current. This makes simplified vector control of the permanent magnet synchronous motor very useful for some special applications that need simple control structure and low cost performance.

The Development of Anti-Windup Scheme for Time Delay Control with Switching Action Using Integral Sliding Surface (적분형 슬라이딩 서피스를 이용한 TDCSA(Time Delay Control With Switching Action)의 와인드업 방지를 위한 기법의 개발)

  • Lee, Seong-Uk;Jang, Pyeong-Hun
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.26 no.8
    • /
    • pp.1534-1544
    • /
    • 2002
  • The TDCSA(Time Delay Control with Switching Action) method, which consists of Time Delay Control(TDC) and a switching action of sliding mode control(SMC), has been proposed as a promising technique in the robust control area, where the plant has unknown dynamics with parameter variations and substantial disturbances are preset. When TDCSA is applied to the plant with saturation nonlinearity, however, the so-called windup phenomena are observed to arise, causing excessive overshoot and instability. The integral element of TDCSA and the saturation element of a plant cause the windup phenomena. There are two integral effects in TDCSA. One is the integral effect occurred by time delay estimation of TDC. Other is the integral term of an integral sliding surface. In order to solve this problem, we have proposed an anti-windup scheme method for TDCSA. The stability of the overall system has been proved for a class of nonlinear system. Experiment results show that the proposed method overcomes the windup problem of the TDCSA.

Steady-State Integral Proportional Integral Controller for PI Motor Speed Controllers

  • Hoo, Choon Lih;Haris, Sallehuddin Mohamed;Chung, Edwin Chin Yau;Mohamed, Nik Abdullah Nik
    • Journal of Power Electronics
    • /
    • v.15 no.1
    • /
    • pp.177-189
    • /
    • 2015
  • The output of the controller is said to exceed the input limits of the plant being controlled when a control system operates in a non-linear region. This process is called the windup phenomenon. The windup phenomenon is not preferable in the control system because it leads to performance degradation, such as overshoot and system instability. Many anti-windup strategies involve switching, where the integral component differently operates between the linear and the non-linear states. The range of state for the non-overshoot performance is better illustrated by the boundary integral error plane than the proportional-integral (PI) plane in windup inspection. This study proposes a PI controller with a separate closed-loop integral controller and reference value set with respect to the input command and external torque. The PI controller is compared with existing conventional proportional integral, conditional integration, tracking back calculation, and integral state prediction schemes by using ScicosLab simulations. The controller is also experimentally verified on a direct current motor under no-load and loading conditions. The proposed controller shows a promising potential with its ability to eliminate overshoot with short settling time using the decoupling mode in both conditions.

Output Feedback Stabilization using Integral Sliding Mode Control (적분 슬라이딩 모드 제어기를 이용한 출력 궤환 안정화)

  • Oh, Seung-Rohk
    • The Transactions of the Korean Institute of Electrical Engineers D
    • /
    • v.52 no.3
    • /
    • pp.142-147
    • /
    • 2003
  • We consider a single-input-single-output nonlinear system which can be represented in a normal form. The nonlinear system has a modeling uncertainties including the input coefficient uncertainty. A high-gain observer is used to estimate the states variables to reject a modeling uncertainty. A globally bounded output feedback integral sliding mode control is proposed to stabilize the closed loop system. The proposed integral sliding mode control can asymptotically stabilize the closed loop system in the presence of input coefficient uncertainty.

INSTRUMENTATION AND CONTROL STRATEGIES FOR AN INTEGRAL PRESSURIZED WATER REACTOR

  • UPADHYAYA, BELLE R.;LISH, MATTHEW R.;HINES, J. WESLEY;TARVER, RYAN A.
    • Nuclear Engineering and Technology
    • /
    • v.47 no.2
    • /
    • pp.148-156
    • /
    • 2015
  • Several vendors have recently been actively pursuing the development of integral pressurized water reactors (iPWRs) that range in power levels from small to large reactors. Integral reactors have the features of minimum vessel penetrations, passive heat removal after reactor shutdown, and modular construction that allow fast plant integration and a secure fuel cycle. The features of an integral reactor limit the options for placing control and safety system instruments. The development of instrumentation and control (I&C) strategies for a large 1,000 MWe iPWR is described. Reactor system modeling-which includes reactor core dynamics, primary heat exchanger, and the steam flashing drum-is an important part of I&C development and validation, and thereby consolidates the overall implementation for a large iPWR. The results of simulation models, control development, and instrumentation features illustrate the systematic approach that is applicable to integral light water reactors.

Effect of Active Control Bearing on Unbalance Response of a Rotor-Bearing System (축-베어링 계의 불균형 응답에 대한 능동 제어 베어링의 효과)

  • 노병후;김경웅
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
    • /
    • 2001.11a
    • /
    • pp.316-321
    • /
    • 2001
  • The paper presents the unbalance response of a rotor-bearing system supported by an active control bearing. The proportional, derivative and integral controls are employed for the control algorithm of an active control bearing to suppress the unbalance response of a rotor-bearing system. Results of analytical investigations on the unbalance responses of a rotor supported by an active control bearing are presented for various control gains. It is found that the unbalance response of a rotor can be greatly suppressed by the proportional, derivative or integral control of the bearing. The proportional control is more effective than the derivative control at low rotational speed, and the derivative control is more effective than the proportional control at high rotational speed. In the case of the integral control of the bearing , the unbalance response of a rotor is increased as a general rule. However, the integral control of the bearing is extremely superior to proportional or derivative control at very low rotational speed.

  • PDF

Effect of Active Control Bearing on Unbalance Response of a Rotor-Bearing System (축-베어링 계의 불균형 응답에 대한 능동 제어 베어링의 효과)

  • 노병후;김경웅
    • Tribology and Lubricants
    • /
    • v.18 no.2
    • /
    • pp.99-104
    • /
    • 2002
  • The paper presents the unbalance response of a rotor-bearing system supported by an active control bearing. The proportional, derivative and integral controls are investigated fur the control algorithm of an active control bearing to suppress the unbalance response of a rotor-bearing system. Results of analytical investigations on the unbalance responses of a rotor supported by an active control bearing are presented for various control gains. It is found that the unbalance response of a rotor can be greatly suppressed by the proportional, derivative or integral control of the bearing. The proportional control is more effective than the derivative control at low rotational speed, and the derivative control is more effective than the proportional control at high rotational speed. In the case of the integral control of the bearing, the unbalance response ova rotor is increased as a general rule. However, the integral control of the bearing is extremely superior to proportional or derivative control at very low rotational speed.