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Nigel H Lovell - One of the best experts on this subject based on the ideXlab platform.
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RESEARCH ARTICLE Preload-Based Starling-Like Control for Rotary Blood Pumps: Numerical Comparison with Pulsatility Control and Constant Speed Operation
2016Co-Authors: Mahdi Mansouri, Robert F Salamonsen, Rini Akmeliawati, Einly Lim, Nigel H LovellAbstract:In this study, we evaluate a preload-based Starling-like controller for implantable rotary blood pumps (IRBPs) using left ventricular end-diastolic pressure (PLVED) as the feedback variable. Simulations are conducted using a validated mathematical model. The controller emulates the response of the natural left ventricle (LV) to changes in PLVED. We report the performance of the preload-based Starling-like controller in comparison with our recently designed pulsatility controller and constant Speed Operation. In handling the transition from a baseline state to test states, which include vigorous exercise, blood loss and a major re-duction in the LV contractility (LVC), the preload controller outperformed pulsatility control and constant Speed Operation in all three test scenarios. In exercise, preload-control achieved an increase of 54 % in mean pump flow (QP) with minimum loading on the LV, while pulsatility control achieved only a 5 % increase in flow and a decrease in mean pump Speed. In a hemorrhage scenario, the preload control maintained the greatest safety margin against LV suction. PLVED for the preload controller was 4.9 mmHg, compared with 0.4 mmHg for the pulsatility controller and 0.2 mmHg for the constant Speed mode. Thi
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preload based starling like control for rotary blood pumps numerical comparison with pulsatility control and constant Speed Operation
PLOS ONE, 2015Co-Authors: Majdi Mansouri, Robert F Salamonsen, Rini Akmeliawati, Nigel H LovellAbstract:In this study, we evaluate a preload-based Starling-like controller for implantable rotary blood pumps (IRBPs) using left ventricular end-diastolic pressure (PLVED) as the feedback variable. Simulations are conducted using a validated mathematical model. The controller emulates the response of the natural left ventricle (LV) to changes in PLVED. We report the performance of the preload-based Starling-like controller in comparison with our recently designed pulsatility controller and constant Speed Operation. In handling the transition from a baseline state to test states, which include vigorous exercise, blood loss and a major reduction in the LV contractility (LVC), the preload controller outperformed pulsatility control and constant Speed Operation in all three test scenarios. In exercise, preload-control achieved an increase of 54% in mean pump flow (QP-) with minimum loading on the LV, while pulsatility control achieved only a 5% increase in flow and a decrease in mean pump Speed. In a hemorrhage scenario, the preload control maintained the greatest safety margin against LV suction. PLVED for the preload controller was 4.9 mmHg, compared with 0.4 mmHg for the pulsatility controller and 0.2 mmHg for the constant Speed mode. This was associated with an adequate mean arterial pressure (MAP) of 84 mmHg. In transition to low LVC, QP- for preload control remained constant at 5.22 L/min with a PLVED of 8.0 mmHg. With regards to pulsatility control, QP- fell to the nonviable level of 2.4 L/min with an associated PLVED of 16 mmHg and a MAP of 55 mmHg. Consequently, pulsatility control was deemed inferior to constant Speed mode with a PLVED of 11 mmHg and a QP- of 5.13 L/min in low LVC scenario. We conclude that pulsatility control imposes a danger to the patient in the severely reduced LVC scenario, which can be overcome by using a preload-based Starling-like control approach.
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preload based starling like control for rotary blood pumps numerical comparison with pulsatility control and constant Speed Operation
PLOS ONE, 2015Co-Authors: Majdi Mansouri, Robert F Salamonsen, Rini Akmeliawati, Einly Lim, Nigel H LovellAbstract:In this study, we evaluate a preload-based Starling-like controller for implantable rotary blood pumps (IRBPs) using left ventricular end-diastolic pressure (PLVED) as the feedback variable. Simulations are conducted using a validated mathematical model. The controller emulates the response of the natural left ventricle (LV) to changes in PLVED. We report the performance of the preload-based Starling-like controller in comparison with our recently designed pulsatility controller and constant Speed Operation. In handling the transition from a baseline state to test states, which include vigorous exercise, blood loss and a major reduction in the LV contractility (LVC), the preload controller outperformed pulsatility control and constant Speed Operation in all three test scenarios. In exercise, preload-control achieved an increase of 54% in mean pump flow ([Formula: see text]) with minimum loading on the LV, while pulsatility control achieved only a 5% increase in flow and a decrease in mean pump Speed. In a hemorrhage scenario, the preload control maintained the greatest safety margin against LV suction. PLVED for the preload controller was 4.9 mmHg, compared with 0.4 mmHg for the pulsatility controller and 0.2 mmHg for the constant Speed mode. This was associated with an adequate mean arterial pressure (MAP) of 84 mmHg. In transition to low LVC, [Formula: see text] for preload control remained constant at 5.22 L/min with a PLVED of 8.0 mmHg. With regards to pulsatility control, [Formula: see text] fell to the nonviable level of 2.4 L/min with an associated PLVED of 16 mmHg and a MAP of 55 mmHg. Consequently, pulsatility control was deemed inferior to constant Speed mode with a PLVED of 11 mmHg and a [Formula: see text] of 5.13 L/min in low LVC scenario. We conclude that pulsatility control imposes a danger to the patient in the severely reduced LVC scenario, which can be overcome by using a preload-based Starling-like control approach.
Majdi Mansouri - One of the best experts on this subject based on the ideXlab platform.
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preload based starling like control for rotary blood pumps numerical comparison with pulsatility control and constant Speed Operation
PLOS ONE, 2015Co-Authors: Majdi Mansouri, Robert F Salamonsen, Rini Akmeliawati, Nigel H LovellAbstract:In this study, we evaluate a preload-based Starling-like controller for implantable rotary blood pumps (IRBPs) using left ventricular end-diastolic pressure (PLVED) as the feedback variable. Simulations are conducted using a validated mathematical model. The controller emulates the response of the natural left ventricle (LV) to changes in PLVED. We report the performance of the preload-based Starling-like controller in comparison with our recently designed pulsatility controller and constant Speed Operation. In handling the transition from a baseline state to test states, which include vigorous exercise, blood loss and a major reduction in the LV contractility (LVC), the preload controller outperformed pulsatility control and constant Speed Operation in all three test scenarios. In exercise, preload-control achieved an increase of 54% in mean pump flow (QP-) with minimum loading on the LV, while pulsatility control achieved only a 5% increase in flow and a decrease in mean pump Speed. In a hemorrhage scenario, the preload control maintained the greatest safety margin against LV suction. PLVED for the preload controller was 4.9 mmHg, compared with 0.4 mmHg for the pulsatility controller and 0.2 mmHg for the constant Speed mode. This was associated with an adequate mean arterial pressure (MAP) of 84 mmHg. In transition to low LVC, QP- for preload control remained constant at 5.22 L/min with a PLVED of 8.0 mmHg. With regards to pulsatility control, QP- fell to the nonviable level of 2.4 L/min with an associated PLVED of 16 mmHg and a MAP of 55 mmHg. Consequently, pulsatility control was deemed inferior to constant Speed mode with a PLVED of 11 mmHg and a QP- of 5.13 L/min in low LVC scenario. We conclude that pulsatility control imposes a danger to the patient in the severely reduced LVC scenario, which can be overcome by using a preload-based Starling-like control approach.
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preload based starling like control for rotary blood pumps numerical comparison with pulsatility control and constant Speed Operation
PLOS ONE, 2015Co-Authors: Majdi Mansouri, Robert F Salamonsen, Rini Akmeliawati, Einly Lim, Nigel H LovellAbstract:In this study, we evaluate a preload-based Starling-like controller for implantable rotary blood pumps (IRBPs) using left ventricular end-diastolic pressure (PLVED) as the feedback variable. Simulations are conducted using a validated mathematical model. The controller emulates the response of the natural left ventricle (LV) to changes in PLVED. We report the performance of the preload-based Starling-like controller in comparison with our recently designed pulsatility controller and constant Speed Operation. In handling the transition from a baseline state to test states, which include vigorous exercise, blood loss and a major reduction in the LV contractility (LVC), the preload controller outperformed pulsatility control and constant Speed Operation in all three test scenarios. In exercise, preload-control achieved an increase of 54% in mean pump flow ([Formula: see text]) with minimum loading on the LV, while pulsatility control achieved only a 5% increase in flow and a decrease in mean pump Speed. In a hemorrhage scenario, the preload control maintained the greatest safety margin against LV suction. PLVED for the preload controller was 4.9 mmHg, compared with 0.4 mmHg for the pulsatility controller and 0.2 mmHg for the constant Speed mode. This was associated with an adequate mean arterial pressure (MAP) of 84 mmHg. In transition to low LVC, [Formula: see text] for preload control remained constant at 5.22 L/min with a PLVED of 8.0 mmHg. With regards to pulsatility control, [Formula: see text] fell to the nonviable level of 2.4 L/min with an associated PLVED of 16 mmHg and a MAP of 55 mmHg. Consequently, pulsatility control was deemed inferior to constant Speed mode with a PLVED of 11 mmHg and a [Formula: see text] of 5.13 L/min in low LVC scenario. We conclude that pulsatility control imposes a danger to the patient in the severely reduced LVC scenario, which can be overcome by using a preload-based Starling-like control approach.
Jinhwan Jung - One of the best experts on this subject based on the ideXlab platform.
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dual inverter control strategy for high Speed Operation of ev induction motors
IEEE Transactions on Industrial Electronics, 2004Co-Authors: Junha Kim, Jinhwan Jung, Kwanghee NamAbstract:An integrated starter/alternator (ISA) is normally designed to have high pole structure (10-14 poles) for high starting torque. However, its back electromotive force (EMF) at the peak revolutions per minute should be less than its battery voltage for the power flow control. For example, the back-EMF of a 12-pole ISA should be 42 V at 6000 r/min. These types of conflicting requirements lead to a nonclassical motor design that has extremely large field-weakening range (8:1/spl sim/10:1). In this paper, we are considering the use of an induction machine instead of a permanent synchronous machine. As an idea for solving the voltage limit problem, two inverters are utilized with an objective of sharing the required voltage. The secondary inverter only takes care of the reactive voltage component that grows very fast in high-Speed Operation. Therefore, an extra voltage source is not required for the secondary inverter. Only a capacitor bank suffices for the secondary inverter.
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A dynamic decoupling control scheme for high-Speed Operation of induction motors
IEEE Transactions on Industrial Electronics, 1999Co-Authors: Jinhwan JungAbstract:In a high-Speed Operation of a vector-controlled induction motor, coupling between d-q current dynamics impairs the characteristics of torque response. The feedforward decoupling scheme does not perform well if an error exists in the motor parameter estimation. We derive a dynamic decoupling condition when the two additional proportional integral current controllers are used. A great advantage of this dynamic decoupling controller is the robustness to the motor parameter estimation errors. Further, we observe that overmodulation methods lead to the violation of the decoupling condition, thereby yielding a poor performance in the high-Speed high-power Operation. As a method of resolving this problem, we propose a decoupling preserving overmodulation algorithm which also enhances the torque transient response. Through simulation and experimental results, we demonstrate the improved performance of the proposed controller.
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pi type decoupling control scheme for high Speed Operation of induction motors
Power Electronics Specialists Conference, 1997Co-Authors: Jinhwan Jung, Sunkyoung Lim, Kwanghee NamAbstract:In the high-Speed Operation of a vector controlled induction motor, decoupling current control is a very important problem. However, the conventional decoupling scheme does not perform well when there are mismatches in the motor parameters. The authors propose a PI type decoupling current controller. A great advantage of this PI type decoupling controller is its robustness to motor parameter errors. Hence, the proposed scheme appears suitable for practical applications where the exact parameters are unknown. Through simulation results, the authors show that the proposed controller achieves the desired performances.
Kwanghee Nam - One of the best experts on this subject based on the ideXlab platform.
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Dual Inverter Strategy for High Speed Operation of HEV Permanent Magnet Synchronous Motor
Conference Record of the 2006 IEEE Industry Applications Conference Forty-First IAS Annual Meeting, 2006Co-Authors: Joon-sik Park, Kwanghee NamAbstract:Bi-directional buck-boost DC/DC converter is normally utilized for high Speed Operation of motors for hybrid electric vehicles (HEV). In this work, a dual inverter strategy is proposed for HEV motor with the purpose of accommodating high Speed Operation without increasing battery voltage. By setting the secondary inverter to take care of only reactive voltage component, the secondary inverter do not carry voltage source other than capacitor bank. DC link voltage regulation is achieved through the control of active power flow.
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dual inverter control strategy for high Speed Operation of ev induction motors
IEEE Transactions on Industrial Electronics, 2004Co-Authors: Junha Kim, Jinhwan Jung, Kwanghee NamAbstract:An integrated starter/alternator (ISA) is normally designed to have high pole structure (10-14 poles) for high starting torque. However, its back electromotive force (EMF) at the peak revolutions per minute should be less than its battery voltage for the power flow control. For example, the back-EMF of a 12-pole ISA should be 42 V at 6000 r/min. These types of conflicting requirements lead to a nonclassical motor design that has extremely large field-weakening range (8:1/spl sim/10:1). In this paper, we are considering the use of an induction machine instead of a permanent synchronous machine. As an idea for solving the voltage limit problem, two inverters are utilized with an objective of sharing the required voltage. The secondary inverter only takes care of the reactive voltage component that grows very fast in high-Speed Operation. Therefore, an extra voltage source is not required for the secondary inverter. Only a capacitor bank suffices for the secondary inverter.
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pi type decoupling control scheme for high Speed Operation of induction motors
Power Electronics Specialists Conference, 1997Co-Authors: Jinhwan Jung, Sunkyoung Lim, Kwanghee NamAbstract:In the high-Speed Operation of a vector controlled induction motor, decoupling current control is a very important problem. However, the conventional decoupling scheme does not perform well when there are mismatches in the motor parameters. The authors propose a PI type decoupling current controller. A great advantage of this PI type decoupling controller is its robustness to motor parameter errors. Hence, the proposed scheme appears suitable for practical applications where the exact parameters are unknown. Through simulation results, the authors show that the proposed controller achieves the desired performances.
Rini Akmeliawati - One of the best experts on this subject based on the ideXlab platform.
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RESEARCH ARTICLE Preload-Based Starling-Like Control for Rotary Blood Pumps: Numerical Comparison with Pulsatility Control and Constant Speed Operation
2016Co-Authors: Mahdi Mansouri, Robert F Salamonsen, Rini Akmeliawati, Einly Lim, Nigel H LovellAbstract:In this study, we evaluate a preload-based Starling-like controller for implantable rotary blood pumps (IRBPs) using left ventricular end-diastolic pressure (PLVED) as the feedback variable. Simulations are conducted using a validated mathematical model. The controller emulates the response of the natural left ventricle (LV) to changes in PLVED. We report the performance of the preload-based Starling-like controller in comparison with our recently designed pulsatility controller and constant Speed Operation. In handling the transition from a baseline state to test states, which include vigorous exercise, blood loss and a major re-duction in the LV contractility (LVC), the preload controller outperformed pulsatility control and constant Speed Operation in all three test scenarios. In exercise, preload-control achieved an increase of 54 % in mean pump flow (QP) with minimum loading on the LV, while pulsatility control achieved only a 5 % increase in flow and a decrease in mean pump Speed. In a hemorrhage scenario, the preload control maintained the greatest safety margin against LV suction. PLVED for the preload controller was 4.9 mmHg, compared with 0.4 mmHg for the pulsatility controller and 0.2 mmHg for the constant Speed mode. Thi
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preload based starling like control for rotary blood pumps numerical comparison with pulsatility control and constant Speed Operation
PLOS ONE, 2015Co-Authors: Majdi Mansouri, Robert F Salamonsen, Rini Akmeliawati, Nigel H LovellAbstract:In this study, we evaluate a preload-based Starling-like controller for implantable rotary blood pumps (IRBPs) using left ventricular end-diastolic pressure (PLVED) as the feedback variable. Simulations are conducted using a validated mathematical model. The controller emulates the response of the natural left ventricle (LV) to changes in PLVED. We report the performance of the preload-based Starling-like controller in comparison with our recently designed pulsatility controller and constant Speed Operation. In handling the transition from a baseline state to test states, which include vigorous exercise, blood loss and a major reduction in the LV contractility (LVC), the preload controller outperformed pulsatility control and constant Speed Operation in all three test scenarios. In exercise, preload-control achieved an increase of 54% in mean pump flow (QP-) with minimum loading on the LV, while pulsatility control achieved only a 5% increase in flow and a decrease in mean pump Speed. In a hemorrhage scenario, the preload control maintained the greatest safety margin against LV suction. PLVED for the preload controller was 4.9 mmHg, compared with 0.4 mmHg for the pulsatility controller and 0.2 mmHg for the constant Speed mode. This was associated with an adequate mean arterial pressure (MAP) of 84 mmHg. In transition to low LVC, QP- for preload control remained constant at 5.22 L/min with a PLVED of 8.0 mmHg. With regards to pulsatility control, QP- fell to the nonviable level of 2.4 L/min with an associated PLVED of 16 mmHg and a MAP of 55 mmHg. Consequently, pulsatility control was deemed inferior to constant Speed mode with a PLVED of 11 mmHg and a QP- of 5.13 L/min in low LVC scenario. We conclude that pulsatility control imposes a danger to the patient in the severely reduced LVC scenario, which can be overcome by using a preload-based Starling-like control approach.
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preload based starling like control for rotary blood pumps numerical comparison with pulsatility control and constant Speed Operation
PLOS ONE, 2015Co-Authors: Majdi Mansouri, Robert F Salamonsen, Rini Akmeliawati, Einly Lim, Nigel H LovellAbstract:In this study, we evaluate a preload-based Starling-like controller for implantable rotary blood pumps (IRBPs) using left ventricular end-diastolic pressure (PLVED) as the feedback variable. Simulations are conducted using a validated mathematical model. The controller emulates the response of the natural left ventricle (LV) to changes in PLVED. We report the performance of the preload-based Starling-like controller in comparison with our recently designed pulsatility controller and constant Speed Operation. In handling the transition from a baseline state to test states, which include vigorous exercise, blood loss and a major reduction in the LV contractility (LVC), the preload controller outperformed pulsatility control and constant Speed Operation in all three test scenarios. In exercise, preload-control achieved an increase of 54% in mean pump flow ([Formula: see text]) with minimum loading on the LV, while pulsatility control achieved only a 5% increase in flow and a decrease in mean pump Speed. In a hemorrhage scenario, the preload control maintained the greatest safety margin against LV suction. PLVED for the preload controller was 4.9 mmHg, compared with 0.4 mmHg for the pulsatility controller and 0.2 mmHg for the constant Speed mode. This was associated with an adequate mean arterial pressure (MAP) of 84 mmHg. In transition to low LVC, [Formula: see text] for preload control remained constant at 5.22 L/min with a PLVED of 8.0 mmHg. With regards to pulsatility control, [Formula: see text] fell to the nonviable level of 2.4 L/min with an associated PLVED of 16 mmHg and a MAP of 55 mmHg. Consequently, pulsatility control was deemed inferior to constant Speed mode with a PLVED of 11 mmHg and a [Formula: see text] of 5.13 L/min in low LVC scenario. We conclude that pulsatility control imposes a danger to the patient in the severely reduced LVC scenario, which can be overcome by using a preload-based Starling-like control approach.
