성인 ADHD와 우울한 성인의 인지통제 결함: 순행성 통제와 반응성 통제 요구도에 따른 AX-CPT 수행 비교

김인용,박태원,김호영 한국인지및생물심리학회 2022 한국심리학회지 인지 및 생물 Vol.34 No.2

This study aimed to explore the characteristics of cognitive control deficits in adult ADHD from the perspective of Dual Mechanism of Control (DMC), which posits that cognitive control operates via two distinct dimensions, i.e., proactive and reactive control. AX-CPT, including nogo trials, was utilized to tap cognitive control processes in a sample of 27 adults with ADHD, 17 adults with depression, and 29 healthy adults. The performance of adults with ADHD was compared to that of adults with depression as well as healthy adults to investigate the effects of depression, which is a common comorbid condition in adult ADHD. AX-CPT is a continuous performance test consisting of four types of cue-probe pairs (AX, AY, BX, BY) and requires participants to respond to a probe based on a preceding cue. AX pairs are target pairs matched with a target response, and other pairs are non-target pairs matched with a non-target response. The proactive control demands were manipulated with the proportion of AX trials(AX-40 vs. AX-70) and the reactive control demands were manipulated with nogo trials(base vs. nogo). The order of the two AX-proportion conditions were counterbalanced, and the base condition and the nogo condition were implemented in order within each AX-proportion condition. The adult ADHD group showed lower accuracy than the depression group and the healthy control group in the performance of BX trials that require proactive inhibitory control. Both the ADHD group and the depression group performed lower than the healthy control group in nogo trials that require reactive inhibitory control. These results suggest that adults with ADHD have a deficit in overall cognitive control, including proactive and reactive control, and the reactive control deficit of adult ADHD may be associated with comorbid depression as well as ADHD itself. 본 연구에서는 순행성 통제(proactive control)와 반응성 통제(reactive control)로 구분되는 기제를 통해 인지통제가 작동한다는 인지통제의 이중기제(Dual Mechanism of Control, DMC) 이론의 관점에서 성인 ADHD의 인지통제 결함의 특성을 탐색하였다. 이를 위해 성인 ADHD 27명, 정상 대조군 성인 29명이 본 연구에 참여하였으며, 성인 ADHD에서 흔히 동반되는 우울이 인지통제에 미치는 영향을 알아보기 위해 ADHD가 아닌 우울한 성인 17명도 참여하였다. 인지통제 과제로 사용된 AX-CPT는 4가지 유형의 단서-탐색자극 쌍(AX, AY, BX, BY)으로 구성되며, AX에는 표적 반응을 나머지 자극 쌍에는 비표적 반응을 하게 하는 연속수행과제이다. 본 연구에서는 표적 반응에 대응하는 단서-탐색자극 쌍인 AX의 비율(AX-40 vs. AX-70)로 순행성 통제의 요구도를, 탐색자극 대신에 반응을 억제해야 하는 nogo 자극이 제시되는 nogo 시행을 이용(기저 vs. nogo 조건)하여 반응성 통제의 요구도를 조작하였다. AX-비율 조건은 역균형화하였으며, AX-비율 조건 내에서 기저 조건, nogo 조건 순으로 실시되었다. 성인 ADHD 집단은 단서를 이용하여 반응을 사전에 준비하는 순행성 통제과정이 전반적으로 저하된 데 비해, 우울 집단은 강력히 편향된 반응을 순행적으로 억제해야 조건(AX-70의 BX)에서만 낮은 수행을 보였다. 또한 반응성 통제에 대한 요구도가 높은 nogo 시행에서는 ADHD 집단과 우울 집단 모두 정상 집단에 비해 낮은 수행을 보였다. 이러한 결과는 성인 ADHD가 순행성 통제와 반응성 통제를 포함한 전반적인 인지통제의 결함을 가짐을 시사하며, 반응성 통제 결함은 이차적 우울의 영향도 혼재되었을 가능성을 시사한다.

Secondary Voltage Control for Reactive Power Sharing in an Islanded Microgrid

Guo, Qian,Wu, Hongyan,Lin, Liaoyuan,Bai, Zhihong,Ma, Hao The Korean Institute of Power Electronics 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.1

Owing to mismatched feeder impedances in an islanded microgrid, the conventional droop control method typically results in errors in reactive power sharing among distributed generation (DG) units. In this study, an improved droop control strategy based on secondary voltage control is proposed to enhance the reactive power sharing accuracy in an islanded microgrid. In a DG local controller, an integral term is introduced into the voltage droop function, in which the voltage compensation signal from the secondary voltage control is utilized as the common reactive power reference for each DG unit. Therefore, accurate reactive power sharing can be realized without any power information exchange among DG units or between DG units and the central controller. Meanwhile, the voltage deviation in the microgrid common bus is removed. Communication in the proposed strategy is simple to implement because the information of the voltage compensation signal is broadcasted from the central controller to each DG unit. The reactive power sharing accuracy is also not sensitive to time-delay mismatch in the communication channels. Simulation and experimental results are provided to validate the effectiveness of the proposed method.

Secondary Voltage Control for Reactive Power Sharing in an Islanded Microgrid

Qian Guo,Hongyan Wu,Liaoyuan Lin,Zhihong Bai,Hao Ma 전력전자학회 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.1

Owing to mismatched feeder impedances in an islanded microgrid, the conventional droop control method typically results in errors in reactive power sharing among distributed generation (DG) units. In this study, an improved droop control strategy based on secondary voltage control is proposed to enhance the reactive power sharing accuracy in an islanded microgrid. In a DG local controller, an integral term is introduced into the voltage droop function, in which the voltage compensation signal from the secondary voltage control is utilized as the common reactive power reference for each DG unit. Therefore, accurate reactive power sharing can be realized without any power information exchange among DG units or between DG units and the central controller. Meanwhile, the voltage deviation in the microgrid common bus is removed. Communication in the proposed strategy is simple to implement because the information of the voltage compensation signal is broadcasted from the central controller to each DG unit. The reactive power sharing accuracy is also not sensitive to time-delay mismatch in the communication channels. Simulation and experimental results are provided to validate the effectiveness of the proposed method.

Improved Reactive Power Sharing for Parallel-operated Inverters in Islanded Microgrids

Walid Issa,Suleiman Sharkh,Tapas Mallick,Mohammad Abusara 전력전자학회 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.3

The unequal impedances of the interconnecting cables between paralleled inverters in the island mode of microgrids cause inaccurate reactive power sharing when the traditional droop control is used. Many studies in the literature adopt low speed communications between the inverters and the central control unit to overcome this problem. However, the losses of this communication link can be very detrimental to the performance of the controller. This paper proposes an improved reactive power-sharing control method. It employs infrequent measurements of the voltage at the point of common coupling (PCC) to estimate the output impedance between the inverters and the PCC and then readjust the voltage droop controller gains accordingly. The controller then reverts to being a traditional droop controller using the newly calculated gains. This increases the immunity of the controller against any losses in the communication links between the central control unit and the inverters. The capability of the proposed control method has been demonstrated by simulation and experimental results using a laboratory scale microgrid.

A Study on Cooperative Control Method to Secure the Reactive Power in the Power System

Lee, Hyun-Chul,Jeong, Ki-Seok,Park, Ji-Ho,Baek, Young-Sik The Korean Institute of Electrical Engineers 2014 The Journal of International Council on Electrical Vol.4 No.3

This paper proposes the cooperative control method between reactive power compensation devices for securing the reactive reserve power of the FACTS in the power system. The Cooperative control consists of the two different methods, such as concurrent and sequence control. This proposed method is used different method according to the normal and abnormal state. The concurrent control is applied for maintaining the bus voltage in desired level when the load of power system has been remarkably increased or decreased. This control method is operated at once by calculating necessary active power capacity based on the voltage difference to each substation voltage and reference voltage in the power system. The sequence control has been used to secure momentary reactive power. The momentary reactive power is processed with the fast control characteristics. Therefore, this control has been managed for improving the voltage stability in the power system. Also, it has been demonstrated by the PSS/E and the Python programs.

An Accurate Reactive Power Sharing Control Strategy for DG Units in a Microgrid

Jinwei He,Yun Wei Li 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

A popular power control and load demand sharing method for distributed generation (DG) units in microgrid is the frequency and voltage droop control. However, in a low voltage microgrid, due to the effects of nontrivial feeder impedance, the conventional droop control is subject to the real and reactive power coupling and steady-state reactive power errors. Furthermore, different microgrid configurations (looped network or radial system) and the different locations of loads make the DG reactive power sharing even more challenging. To improve the power control and sharing accuracy, this paper proposes a control strategy that estimates the reactive power sharing errors of DG units through injecting small real power disturbances. With the estimated reactive power errors, the conventional reactive power droop control can be improved with zero steadystate sharing error, just like the real power sharing through frequency droop control. The proposed method can work in both grid-connected mode and islanding mode and is effective for all types of microgrid configurations and load locations.

PWM 전력 컨버터를 이용한 배전용 무효전력 보상기 제어

고지호,김용현,김재홍,김일환 濟州大學校 産業技術硏究所 2000 산업기술연구소논문집 Vol.11 No.1

This paper presents the control method of reactive power in distribution system using PWM power converter. The PWM power converter controlled by space vector PWM method is voltage source type using IGBT switching device. Using the Park's transformation, three phase load current can be written in terms of component α and β current in a synchronously rotating reference frame. Two axis. the direct axis. α. and the quadrature axis. β, mean the active and reactive component in load current. Also. two components appear as de quantities in that frame. So it is easy to control the reactive power by controlling the d axis currents. And in accordance with the change of reactive power in load side. PWM power converter compensate the reactive power by generating the reactive current to the load side using PI control. To verify the theoretical analysis. results of computer simulation and experiment are presented to support the discussion

PWM 전력 컨버터를 이용한 배전용 무효전력 보상기 제어

고지호,김용현,김재홍,김일환 제주대학교 산업기술연구소 2000 尖端技術硏究所論文集 Vol.11 No.1

This paper presents the control method of reactive power in distribution system using PWM power converter. The PWM power converter controlled by space vector PWM method is voltage source type using IGBT switching device. Using the Park's transformation, three phase load current can be written in terms of component α and β current in a synchronously rotating reference frame. Two axis, the direct axis, α, and the quadrature axis, β, mean the active and reactive component in load current. Also, two components appear as dc quantities in that frame. So it is easy to control the reactive power by controlling the d axis currents. And in accordance with the change of reactive power in load side, PWM power converter compensate the reactive power by generating the reactive current to the load side using PI control. To verify the theoretical analysis, results of computer simulation and experiment are presented to support the discussion

Improved Reactive Power Sharing for Parallel-operated Inverters in Islanded Microgrids

Issa, Walid,Sharkh, Suleiman,Mallick, Tapas,Abusara, Mohammad The Korean Institute of Power Electronics 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.3

The unequal impedances of the interconnecting cables between paralleled inverters in the island mode of microgrids cause inaccurate reactive power sharing when the traditional droop control is used. Many studies in the literature adopt low speed communications between the inverters and the central control unit to overcome this problem. However, the losses of this communication link can be very detrimental to the performance of the controller. This paper proposes an improved reactive power-sharing control method. It employs infrequent measurements of the voltage at the point of common coupling (PCC) to estimate the output impedance between the inverters and the PCC and then readjust the voltage droop controller gains accordingly. The controller then reverts to being a traditional droop controller using the newly calculated gains. This increases the immunity of the controller against any losses in the communication links between the central control unit and the inverters. The capability of the proposed control method has been demonstrated by simulation and experimental results using a laboratory scale microgrid.

High-Performance Sensorless Control of PSM Using Back-EMF and Reactive Power

Guen Bo Lee,Jun Seong Park,Sung Hun Lee,Young Ahn Kwon 제어로봇시스템학회 2009 제어로봇시스템학회 국제학술대회 논문집 Vol.2009 No.8

This Paper investigates a high-performance strategy for speed sensorless control of a permanent magnet synchronous motor. Two speed sensorless controls using back-뜰 뭉 reactive power are analyzed in this paper, and these two speed estimations are appropriately applied according to the steady and transient states for a high-performance sensorless control. The proposed sensorless control algorithm has a better performance compared to the conventional control algorithms.