Method for calculating coordination control weights in distributed drive electric vehicles

A device for calculating coordination control weights in a distributed drive electric vehicle, comprising:

• a dataset construction module;
• a category classification module;
• a distance calculation module;
• a weight factor determination module;
• an objective function construction module;
• and
• a solution module;
• the dataset construction module is configured for constructing a vehicle motion state dataset;
• wherein a vehicle motion state data in the vehicle motion state dataset is characteristic parameters related to a lateral stability state;
• the category classification module is configured for performing a cluster analysis on the vehicle motion state data;
• dividing the vehicle motion state data into three categories:
• a stable state category, a transition state category, and an unstable state category, and determining a cluster center for each of the three categories;
• the distance calculation module is configured for determining a midpoint of a line connecting the cluster center of the stable state category and the cluster center of the transition state category, and calculating a Euclidean distance between the midpoint and the cluster center of the stable state category, denoted as the first distance;
• and calculating a Euclidean distance between the cluster center of the stable state category and the cluster center of the transition state category, denoted as a second distance;
• and
• calculating a Euclidean distance between the cluster center of the stable state category and the cluster center of the unstable state category, denoted as a third distance;
• and calculating a Euclidean distance between a current vehicle motion state data and the cluster center of the stable state category, denoted as a fourth distance;
• the weight factor determination module is configured for determining weight factors for an objective function of an Active Front Steering/Direct Yaw moment Control (AFS/DYC) coordination controller based on a relationship between the first distance, the second distance, the third distance, and the fourth distance;
• the objective function construction module is configured for constructing the objective function of the AFS/DYC coordination controller using the weight factors;
• and
• the solution module is configured for solving the objective function of the AFS/DYC coordination controller to obtain optimal weight factors for an AFS system and a DYC system;
• the weight factor determination module is further configured for determining the weight factors by a following formula expressed as:
• λ
• 1
• ,
• λ
• 2
• =
• {
• 0.5
• ,
• 0.25
• if
• ⁢
• xx
• 1
• <
• L
• 1
• ;
• 0.5
• -
• 0.5
• *
• (
• xx
• 1
• -
• L
• 1
• )
• 2
• (
• L
• 1
• -
• L
• 2
• )
• 2
• ,
• 0.75
• -
• λ
• 1
• if
• ⁢
• L
• 1
• <
• xx
• 1
• <
• (
• L
• 1
• -
• L
• 2
• )
• 2
• ;
• 0.25
• +
• 0.5
• *
• (
• 1
• -
• xx
• 1
• -
• L
• 1
• L
• 2
• -
• L
• 1
• )
• 2
• ,
• 0.75
• -
• λ
• 1
• if
• ⁢
• (
• L
• 1
• -
• L
• 2
• )
• 2
• <
• xx
• 1
• <
• L
• 2
• ;
• 0.25
• ,
• 0.5
• -
• 0.5
• *
• (
• xx
• 1
• -
• L
• 2
• )
• 2
• (
• L
• 3
• -
• L
• 2
• )
• 2
• if
• ⁢
• L
• 2
• <
• xx
• 1
• <
• (
• L
• 2
• -
• L
• 3
• )
• 2
• ;
• 0.25
• ,
• 0.25
• +
• 0.5
• *
• (
• 1
• -
• xx
• 1
• -
• L
• 2
• L
• 3
• -
• L
• 2
• )
• if
• ⁢
• (
• L
• 2
• -
• L
• 3
• )
• 2
• <
• xx
• 1
• <
• L
• 3
• ;
• 0.25
• ,
• 0.25
• if
• ⁢
• xx
• 1
• >
• L
• 3
• ;
• λ
• 3
• =
• 1
• -
• λ
• 1
• -
• λ
• 2
• ;
• and
• wherein λ1 represents a weight factor related to a lateral displacement;
• λ2 represents a weight factor related to a yaw angular velocity;
• λ3 represents a weight factor related to a sideslip angle;
• xx1 is the fourth distance;
• L1 is the first distance;
• L2 is the second distance;
• L3 is the third distance;
• and
• the objective function of the AFS/DYC coordination controller is expressed by a following formula:
• J
• =
• λ
• 1
• ⁢
• ∑
• i
• =
• 1
• N
• ❘
• "\[LeftBracketingBar]"
• e
• d
• ⁢
• i
• ❘
• "\[RightBracketingBar]"
• N
• ⁢
• ❘
• "\[LeftBracketingBar]"
• e
• dmax
• ❘
• "\[RightBracketingBar]"
• +
• λ
• 2
• ⁢
• ∑
• i
• =
• 1
• N
• ❘
• "\[LeftBracketingBar]"
• β
• i
• -
• β
• r
• ⁢
• e
• ⁢
• f
• ❘
• "\[RightBracketingBar]"
• N
• ⁢
• ❘
• "\[LeftBracketingBar]"
• β
• max
• ❘
• "\[RightBracketingBar]"
• +
• λ
• 3
• ⁢
• ∑
• i
• =
• 1
• N
• ❘
• "\[LeftBracketingBar]"
• w
• i
• -
• w
• r
• ⁢
• e
• ⁢
• f
• ❘
• "\[RightBracketingBar]"
• N
• ⁢
• ❘
• "\[LeftBracketingBar]"
• w
• max
• ❘
• "\[RightBracketingBar]"
• wherein J represents an objective function value;
• λ1 represents the weight factor related to the lateral displacement;
• λ2 represents the weight factor related to the yaw angular velocity;
• λ3 represents the weight factor related to the sideslip angle;
• N is the number of sampling instants;
• edi is a lateral displacement deviation at an i-th sampling instant;
• edmax is a maximum lateral displacement deviation;
• βi is a sideslip angle at the i-th sampling instant;
• βref is a reference sideslip angle;
• βmax is a maximum sideslip angle;
• wi is a yaw angular velocity at the i-th sampling instant;
• wref is a reference yaw angular velocity;
• and wmax is a maximum yaw angular velocity;
• and
• edi, βi, and wi are determined according to a discrete vehicle motion differential equation which is related to the optimal weight factor of the AFS system.