The general configuration of CEV1 electric vehicle’s electrical system and the design scheme of its control sequence are presented, which are modularized by using VMU as master control unit, PMU as power management u...The general configuration of CEV1 electric vehicle’s electrical system and the design scheme of its control sequence are presented, which are modularized by using VMU as master control unit, PMU as power management unit, BMU as battery management unit. It is a rather advanced and practical general design scheme of electric vehicle, because the division of its module function is definite, which is advantage for research, manufacture and maintenance.展开更多
In this paper, a robust model predictive control approach is proposed for a class of uncertain systems with time-varying, linear fractional transformation perturbations. By adopting a sequence of feedback control laws...In this paper, a robust model predictive control approach is proposed for a class of uncertain systems with time-varying, linear fractional transformation perturbations. By adopting a sequence of feedback control laws instead of a single one, the control performance can be improved and the region of attraction can be enlarged compared with the existing model predictive control (MPC) approaches. Moreover, a synthesis approach of MPC is developed to achieve high performance with lower on-line computational burden. The effectiveness of the proposed approach is verified by simulation examples.展开更多
The world’s energy consumption and power generation demand will continue to rise.Furthermore,the bulk of the energy resources needed to satisfy the rising demand is far from the load centers.The aforementioned requir...The world’s energy consumption and power generation demand will continue to rise.Furthermore,the bulk of the energy resources needed to satisfy the rising demand is far from the load centers.The aforementioned requires long-distance transmission systems and one way to accomplish this is to use high voltage direct current(HVDC)transmission systems.The main technical issues for HVDC transmission systems are loss of synchronism,variation of quadrature currents,amplitude,the inability of station 1(rectifier),and station 2(inverter)to either inject,or absorb active,or reactive power in the network in any circumstances(before a fault occurs,during having a fault in network and after a fault cleared),and the variations of power transfer capabilities.Additionally,faults impact power quality such as voltage dips and power line outage time.This paper presents a method of overcoming the aforementioned technical issues using voltage-source converter(VSC)based HVDC transmission systems with SCADA VIEWER software and dynamic grid simulator.The benefits include having a higher capacity transmission system and proposed best method for control of active and reactive power transfer capabilities.Simulation results obtained using MATLAB validated the experimental results from SCADA Viewer software.The results indicate that the station’s rectifier or inverter can either inject or absorb either active power or reactive power in any circumstance.Also,the reverse power flow under different modes of operation can ride through faults.At a 100.0%power transfer rate,the rectifier injected 775.0 W into the network.At a 0.0%power transfer rate,the rectifier injected 164.0 W into the network.At a-100.0%rated power,the rectifier injected 1264.0 W into the network and direction was also changed.展开更多
Under complex grid conditions,the grid voltage usually has an imbalance,low order harmonics,and a small of DC bias.When the grid voltage contains low order harmonics and a small amount of DC bias component,the inverte...Under complex grid conditions,the grid voltage usually has an imbalance,low order harmonics,and a small of DC bias.When the grid voltage contains low order harmonics and a small amount of DC bias component,the inverter’s output current cannot meet the grid connection requirements,and there is a three-phase current imbalance in the control strategy of common VSG under unbalanced voltage.A theoretical analysis of non-ideal power grids is carried out,and a VSG control strategy under complex operating conditions is proposed.Firstly,the third-order generalized integrator(TOGI)is used to eliminate the influence of the DC component of grid voltage.An improved delay signal cancellation(DSC)method is proposed to control the balance current and power fluctuation under unbalanced voltage based on the method of common VSG positive and negative sequence separation,It also eliminates the harmonic of command current.Then,the improved quasi proportional resonant controller(QPR)cascaded PI is used to suppress the harmonic current further so that the harmonic content of grid-connected current can meet the grid-connected requirements and achieve the three-phase current balance.Finally,the proposed strategy is verified by simulation under the control objectives of the current balance,active power,and reactive power constant.展开更多
The Pseudopleuronectes americanus antifreeze protein gene was synthesized and control sequences were added such as 35S promoter and nos terminator that can facilitate the transcription and Ω sequence and Kozak sequen...The Pseudopleuronectes americanus antifreeze protein gene was synthesized and control sequences were added such as 35S promoter and nos terminator that can facilitate the transcription and Ω sequence and Kozak sequence that can improve the expression in translation level, the high expression cassette of antifreeze protein was constructed. This cassette was connected to pBI121.1 and finally got the high expression vector pBRTSAFP introduced into the maize callus. The expression of gus gene that linked to the antifreeze protein gene was detected, and the results was that the gus gene can express strongly and instantaneously.展开更多
[Object] This study was conducted to explore the genetic diversity and structure of the wild Repomucenus curvicornis inhabiting Liaoning Coast, China. [Method] The mitochondrial COⅠ gene and control region(CR) were...[Object] This study was conducted to explore the genetic diversity and structure of the wild Repomucenus curvicornis inhabiting Liaoning Coast, China. [Method] The mitochondrial COⅠ gene and control region(CR) were PCR amplified from the wild R. curvicornis populations from the Liaodong Bay(n=22) and the northern Yellow Sea(n=18), sequenced and analyzed for genetic diversity. [Result] The contents of A, T, C and G of 624 bp COⅠ gene were 24.09%, 31.04%, 25.28%, and 19.59%, and those of 460 bp CR fragment were 32.96%, 32.80%, 14.86% and 19.38%, respectively. The total number of variable sites, average number of nucleotide differences( k), haplotype diversity(H) and nucleotide diversity(π) based on COⅠ gene were 38, 4.67,(0.96±0.02) and(0.007 5±0.004 2), and those based on CR fragment were 26, 3.35,(0.97 ±0.02) and(0.007 3±0.004 3), respectively. Based on mitochondrial COⅠ gene and CR, the genetic diversity of Liaodong Bay population was lower than that of the northern Yellow Sea population. The AMOVA analysis based on CR fragments revealed almost significant genetic divergence between the Liaodong Bay and the northern Yellow Sea populations, while there was no significant genetic divergence based on COⅠ gene. The results showed that CR and COⅠ gene are effective molecular markers for detecting the genetic diversity of R. curvicornis population, while CR is more reliable than COⅠ gene in detecting the genetic structure. [Conclusion] CR is an appropriate marker for genetic analysis of marine fish population.展开更多
The theory of shared control combines organically the control of every controlled ele-ments and with it all the controlled elements share the same control element. Applying theschemes of shared control searched by ass...The theory of shared control combines organically the control of every controlled ele-ments and with it all the controlled elements share the same control element. Applying theschemes of shared control searched by assembly programs, an integrated control of all the ele-ments is fulfilled. The distinguishing point of the method is that the maximum control output canbe obtained with the least input information. Hence it is the optimum for the conversion of com-bination states. Finally, a thared rotary valve is designed, and it is the simplest with only onegroup of control holes.展开更多
Sequenced-defined oligomer has been emerged as one of the hot topics in polymer chemistry due to its capability of precisely controlling both chain length and monomer sequence.Recent efforts have focused on developmen...Sequenced-defined oligomer has been emerged as one of the hot topics in polymer chemistry due to its capability of precisely controlling both chain length and monomer sequence.Recent efforts have focused on development of synthetic methodologies using state-ofthe-art chemistry tools.However,investigating the impact of minor changes in monomer sequence on physical properties of these materials is still underdeveloped.Herein,four sequenced pentamers are synthesized by a reversible addition-fragmentation chain transfer(RAFT)single unit monomer insertion technique,in which a base pentamer possesses a relatively rigid backbone comprising of five cyclic monomer units.One of the cyclic units in this base pentamer is replaced by an acyclic monomer at different locations(the 1st,3rd and 5th unit)to produce three modified pentamers,which leads to a significant decrease of glass transition temperature(Tg)compared to the base pentamer.Meanwhile,the modified pentamers with identical primary structures but distinct monomer sequences also present different Tg values depending on the position of the acyclic monomer unit.The middle(3rd)position of the acyclic unit causes profound decrease of Tg due to its increased molecular flexibility.These synthetic pentamers have been demonstrated to be excellent oligomeric plasticizers to modulate thermal transitions of bulk polymer materials.展开更多
Built-in-test (BIT) is responsible for equipment fault detection, so the test data correct- ness directly influences diagnosis results. Equipment suffers all kinds of environment stresses, such as temperature, vibra...Built-in-test (BIT) is responsible for equipment fault detection, so the test data correct- ness directly influences diagnosis results. Equipment suffers all kinds of environment stresses, such as temperature, vibration, and electromagnetic stress. As embedded testing facility, BIT also suffers from these stresses and the interferences/faults are caused, so that the test course is influenced, resulting in incredible results. Therefore it is necessary to monitor test data and judge test failures. Stress monitor and BIT self-diagnosis would redound to BIT reliability, but the existing anti- jamming researches are mainly safeguard design and signal process. This paper focuses on test results monitor and BIT equipment (BITE) failure judge, and a series of improved approaches is proposed. Firstly the stress influences on components are illustrated and the effects on the diagnosis results are summarized. Secondly a composite BIT program is proposed with information integra- tion, and a stress monitor program is given. Thirdly, based on the detailed analysis of system faults and forms of BIT results, the test sequence control method is proposed. It assists BITE failure judge and reduces error probability. Finally the validation cases prove that these approaches enhance credibility.展开更多
Monomer sequence influences the properties and applications of polymers.Consequently,massive efforts have been made to implement sequence control of polymers.In this work,we developed a computer-aided droplet-flow pol...Monomer sequence influences the properties and applications of polymers.Consequently,massive efforts have been made to implement sequence control of polymers.In this work,we developed a computer-aided droplet-flow polymerization based on photo-controlled reversible-deactivation radical polymerization(photo-RDRP),enabling synthesis of gradient copolymers of tunable sequential arrangements,low dispersity and good structural fidelity from various monomers without following their intrinsic reactivities,which is a key limitation in sequence control.The obtained gradient copolymers exhibit unique thermal properties and stimulus responsiveness comparing with the random and block counterparts,and their glass transition behaviour could be regulated by the gradient tendency.We believe that the unprecedented gradient photo-RDRP based on flow synthesis opens a robust and versatile avenue to streamline the synthesis of well-defined gradient polymers,and is compatible with other polymerization mechanisms.展开更多
We consider a finite horizon,zero-sum linear quadratic differential game.The feature of this game is that a weight matrix of the minimiser’s control cost in the cost functional is singular.Due to this singularity,the...We consider a finite horizon,zero-sum linear quadratic differential game.The feature of this game is that a weight matrix of the minimiser’s control cost in the cost functional is singular.Due to this singularity,the game can be solved neither by applying the Isaacs MinMax principle nor using the Bellman–Isaacs equation approach,i.e.this game is singular.Aprevious paper of one of the authors analysed such a game in the case where the cost functional does not contain the minimiser’s control cost at all,i.e.the weight matrix of this cost equals zero.In this case,all coordinates of the minimiser’s control are singular.In the present paper,we study the general case where the weight matrix of the minimiser’s control cost,being singular,is not,in general,zero.This means that only a part of the coordinates of the minimiser’s control is singular,while others are regular.The considered game is treated by a regularisation,i.e.by its approximate conversion to an auxiliary regular game.The latter has the same equation of dynamics and a similar cost functional augmented by an integral of the squares of the singular control coordinates with a small positive weight.Thus,the auxiliary game is a partial cheap control differential game.Based on a singular perturbation’s asymptotic analysis of this auxiliary game,the existence of the value of the original(singular)game is established,and its expression is obtained.The maximiser’s optimal state feedback strategy and the minimising control sequence in the original game are designed.It is shown that the coordinates of the minimising control sequence,corresponding to the regular coordinates of the minimiser’s control,are point-wise convergent in the class of regular functions.The optimal trajectory sequence and the optimal trajectory in the considered singular game also are obtained.An illustrative example is presented.展开更多
文摘The general configuration of CEV1 electric vehicle’s electrical system and the design scheme of its control sequence are presented, which are modularized by using VMU as master control unit, PMU as power management unit, BMU as battery management unit. It is a rather advanced and practical general design scheme of electric vehicle, because the division of its module function is definite, which is advantage for research, manufacture and maintenance.
基金supported by National Natural Science Foundation of China (No. 60934007, No. 61074060)China Postdoctoral Science Foundation (No. 20090460627)+1 种基金Shanghai Postdoctoral Scientific Program (No. 10R21414600)China Postdoctoral Science Foundation Special Support (No. 201003272)
文摘In this paper, a robust model predictive control approach is proposed for a class of uncertain systems with time-varying, linear fractional transformation perturbations. By adopting a sequence of feedback control laws instead of a single one, the control performance can be improved and the region of attraction can be enlarged compared with the existing model predictive control (MPC) approaches. Moreover, a synthesis approach of MPC is developed to achieve high performance with lower on-line computational burden. The effectiveness of the proposed approach is verified by simulation examples.
基金support through GrantNo.(600005-Z17X0234)Quanzhou Science and Technology Bureau for financial support through Grant No.(2018Z010)+2 种基金Huaqiao University through Grant No.(17BS201)the Fujian Provincial Department of Science and Technology for financial support through Grant(2018J05121)Authors are also grateful for financial support from the Fujian Provincial Department of Science and Technology through Grant Nos.(2021I0014)and(2018J05121).
文摘The world’s energy consumption and power generation demand will continue to rise.Furthermore,the bulk of the energy resources needed to satisfy the rising demand is far from the load centers.The aforementioned requires long-distance transmission systems and one way to accomplish this is to use high voltage direct current(HVDC)transmission systems.The main technical issues for HVDC transmission systems are loss of synchronism,variation of quadrature currents,amplitude,the inability of station 1(rectifier),and station 2(inverter)to either inject,or absorb active,or reactive power in the network in any circumstances(before a fault occurs,during having a fault in network and after a fault cleared),and the variations of power transfer capabilities.Additionally,faults impact power quality such as voltage dips and power line outage time.This paper presents a method of overcoming the aforementioned technical issues using voltage-source converter(VSC)based HVDC transmission systems with SCADA VIEWER software and dynamic grid simulator.The benefits include having a higher capacity transmission system and proposed best method for control of active and reactive power transfer capabilities.Simulation results obtained using MATLAB validated the experimental results from SCADA Viewer software.The results indicate that the station’s rectifier or inverter can either inject or absorb either active power or reactive power in any circumstance.Also,the reverse power flow under different modes of operation can ride through faults.At a 100.0%power transfer rate,the rectifier injected 775.0 W into the network.At a 0.0%power transfer rate,the rectifier injected 164.0 W into the network.At a-100.0%rated power,the rectifier injected 1264.0 W into the network and direction was also changed.
基金National Natural Science Foundation of China(61863023).
文摘Under complex grid conditions,the grid voltage usually has an imbalance,low order harmonics,and a small of DC bias.When the grid voltage contains low order harmonics and a small amount of DC bias component,the inverter’s output current cannot meet the grid connection requirements,and there is a three-phase current imbalance in the control strategy of common VSG under unbalanced voltage.A theoretical analysis of non-ideal power grids is carried out,and a VSG control strategy under complex operating conditions is proposed.Firstly,the third-order generalized integrator(TOGI)is used to eliminate the influence of the DC component of grid voltage.An improved delay signal cancellation(DSC)method is proposed to control the balance current and power fluctuation under unbalanced voltage based on the method of common VSG positive and negative sequence separation,It also eliminates the harmonic of command current.Then,the improved quasi proportional resonant controller(QPR)cascaded PI is used to suppress the harmonic current further so that the harmonic content of grid-connected current can meet the grid-connected requirements and achieve the three-phase current balance.Finally,the proposed strategy is verified by simulation under the control objectives of the current balance,active power,and reactive power constant.
基金Supported by National Transgenic Plant Research and.Industrialization Foundation(J00-B-003-04)
文摘The Pseudopleuronectes americanus antifreeze protein gene was synthesized and control sequences were added such as 35S promoter and nos terminator that can facilitate the transcription and Ω sequence and Kozak sequence that can improve the expression in translation level, the high expression cassette of antifreeze protein was constructed. This cassette was connected to pBI121.1 and finally got the high expression vector pBRTSAFP introduced into the maize callus. The expression of gus gene that linked to the antifreeze protein gene was detected, and the results was that the gus gene can express strongly and instantaneously.
基金Supported by the National Key R&D Program of China(2017YFC1404400)The National Natural Science Foundation of China(31770458)
文摘[Object] This study was conducted to explore the genetic diversity and structure of the wild Repomucenus curvicornis inhabiting Liaoning Coast, China. [Method] The mitochondrial COⅠ gene and control region(CR) were PCR amplified from the wild R. curvicornis populations from the Liaodong Bay(n=22) and the northern Yellow Sea(n=18), sequenced and analyzed for genetic diversity. [Result] The contents of A, T, C and G of 624 bp COⅠ gene were 24.09%, 31.04%, 25.28%, and 19.59%, and those of 460 bp CR fragment were 32.96%, 32.80%, 14.86% and 19.38%, respectively. The total number of variable sites, average number of nucleotide differences( k), haplotype diversity(H) and nucleotide diversity(π) based on COⅠ gene were 38, 4.67,(0.96±0.02) and(0.007 5±0.004 2), and those based on CR fragment were 26, 3.35,(0.97 ±0.02) and(0.007 3±0.004 3), respectively. Based on mitochondrial COⅠ gene and CR, the genetic diversity of Liaodong Bay population was lower than that of the northern Yellow Sea population. The AMOVA analysis based on CR fragments revealed almost significant genetic divergence between the Liaodong Bay and the northern Yellow Sea populations, while there was no significant genetic divergence based on COⅠ gene. The results showed that CR and COⅠ gene are effective molecular markers for detecting the genetic diversity of R. curvicornis population, while CR is more reliable than COⅠ gene in detecting the genetic structure. [Conclusion] CR is an appropriate marker for genetic analysis of marine fish population.
文摘The theory of shared control combines organically the control of every controlled ele-ments and with it all the controlled elements share the same control element. Applying theschemes of shared control searched by assembly programs, an integrated control of all the ele-ments is fulfilled. The distinguishing point of the method is that the maximum control output canbe obtained with the least input information. Hence it is the optimum for the conversion of com-bination states. Finally, a thared rotary valve is designed, and it is the simplest with only onegroup of control holes.
基金the Australian Research Council(ARC)and UNSW Sydney for the financial support under the schemes of Future Fellowship(No.FT160100095)and Startup Fund。
文摘Sequenced-defined oligomer has been emerged as one of the hot topics in polymer chemistry due to its capability of precisely controlling both chain length and monomer sequence.Recent efforts have focused on development of synthetic methodologies using state-ofthe-art chemistry tools.However,investigating the impact of minor changes in monomer sequence on physical properties of these materials is still underdeveloped.Herein,four sequenced pentamers are synthesized by a reversible addition-fragmentation chain transfer(RAFT)single unit monomer insertion technique,in which a base pentamer possesses a relatively rigid backbone comprising of five cyclic monomer units.One of the cyclic units in this base pentamer is replaced by an acyclic monomer at different locations(the 1st,3rd and 5th unit)to produce three modified pentamers,which leads to a significant decrease of glass transition temperature(Tg)compared to the base pentamer.Meanwhile,the modified pentamers with identical primary structures but distinct monomer sequences also present different Tg values depending on the position of the acyclic monomer unit.The middle(3rd)position of the acyclic unit causes profound decrease of Tg due to its increased molecular flexibility.These synthetic pentamers have been demonstrated to be excellent oligomeric plasticizers to modulate thermal transitions of bulk polymer materials.
基金supported by the Ministry Level Project of China
文摘Built-in-test (BIT) is responsible for equipment fault detection, so the test data correct- ness directly influences diagnosis results. Equipment suffers all kinds of environment stresses, such as temperature, vibration, and electromagnetic stress. As embedded testing facility, BIT also suffers from these stresses and the interferences/faults are caused, so that the test course is influenced, resulting in incredible results. Therefore it is necessary to monitor test data and judge test failures. Stress monitor and BIT self-diagnosis would redound to BIT reliability, but the existing anti- jamming researches are mainly safeguard design and signal process. This paper focuses on test results monitor and BIT equipment (BITE) failure judge, and a series of improved approaches is proposed. Firstly the stress influences on components are illustrated and the effects on the diagnosis results are summarized. Secondly a composite BIT program is proposed with information integra- tion, and a stress monitor program is given. Thirdly, based on the detailed analysis of system faults and forms of BIT results, the test sequence control method is proposed. It assists BITE failure judge and reduces error probability. Finally the validation cases prove that these approaches enhance credibility.
基金This work was supported by the National Natural Science Foundation of China(21704016,21971044).
文摘Monomer sequence influences the properties and applications of polymers.Consequently,massive efforts have been made to implement sequence control of polymers.In this work,we developed a computer-aided droplet-flow polymerization based on photo-controlled reversible-deactivation radical polymerization(photo-RDRP),enabling synthesis of gradient copolymers of tunable sequential arrangements,low dispersity and good structural fidelity from various monomers without following their intrinsic reactivities,which is a key limitation in sequence control.The obtained gradient copolymers exhibit unique thermal properties and stimulus responsiveness comparing with the random and block counterparts,and their glass transition behaviour could be regulated by the gradient tendency.We believe that the unprecedented gradient photo-RDRP based on flow synthesis opens a robust and versatile avenue to streamline the synthesis of well-defined gradient polymers,and is compatible with other polymerization mechanisms.
文摘We consider a finite horizon,zero-sum linear quadratic differential game.The feature of this game is that a weight matrix of the minimiser’s control cost in the cost functional is singular.Due to this singularity,the game can be solved neither by applying the Isaacs MinMax principle nor using the Bellman–Isaacs equation approach,i.e.this game is singular.Aprevious paper of one of the authors analysed such a game in the case where the cost functional does not contain the minimiser’s control cost at all,i.e.the weight matrix of this cost equals zero.In this case,all coordinates of the minimiser’s control are singular.In the present paper,we study the general case where the weight matrix of the minimiser’s control cost,being singular,is not,in general,zero.This means that only a part of the coordinates of the minimiser’s control is singular,while others are regular.The considered game is treated by a regularisation,i.e.by its approximate conversion to an auxiliary regular game.The latter has the same equation of dynamics and a similar cost functional augmented by an integral of the squares of the singular control coordinates with a small positive weight.Thus,the auxiliary game is a partial cheap control differential game.Based on a singular perturbation’s asymptotic analysis of this auxiliary game,the existence of the value of the original(singular)game is established,and its expression is obtained.The maximiser’s optimal state feedback strategy and the minimising control sequence in the original game are designed.It is shown that the coordinates of the minimising control sequence,corresponding to the regular coordinates of the minimiser’s control,are point-wise convergent in the class of regular functions.The optimal trajectory sequence and the optimal trajectory in the considered singular game also are obtained.An illustrative example is presented.