Summary of the invention
Do not consider flywheel self angular momentum and may cause the problem that flywheel moment is saturated so that can't finish the work in order to overcome traditional moment distribution method, also in order to overcome the not high problem of QUADRATIC PROGRAMMING METHOD FOR solution complexity and efficient, the present invention proposes a kind of single shaft batch counteraction flyback moment based on angular momentum nargin and optimize distribution method.
Described single shaft batch counteraction flyback moment based on angular momentum nargin is optimized distribution method and be may further comprise the steps:
Step 1: set up the single shaft mathematical model of counteraction flyback moment distribution in batches.Suppose on certain axle of aircraft n counteraction flyback to be housed, then the installation matrix of this flywheel group can be written as
System is expressed as u to this expectation moment
c, the instruction moment that each divided flywheel is fitted on is designated as
Then expect to satisfy u between the moment and instruction moment
c=I
Tu
w, this formula also is the constraint condition of differentiate optimization problem simultaneously.
Step 2: the energy-optimised distribution method of deriving.Because the energy consumption of flywheel system and the output torque of each counteraction flyback are closely bound up, therefore, utilize the flywheel moment vector to be constructed as follows the energy indexes function
Then energy-optimised allocation strategy can be expressed as following optimization problem:
Adopt method of Lagrange multipliers structure Lagrangian function to be
With Lagrangian function respectively to u
wAsk local derviation can draw following formula with λ,
Obtain after the arrangement:
Simultaneous can obtain single shaft counteraction flyback moment optimization allocation strategy in batches, that is:
Step 3: in conjunction with the concept of angular momentum nargin, derive and optimize distribution method in batches.The angular momentum initial value of supposing flywheel system is H
W0=[H
W01H
W02H
W0n], the angular momentum nargin vector that then defines the flywheel group is
H wherein
WmBe the maximum angular momentum that flywheel can reach, H
w=[H
W1H
W2H
Wn] be the output angle momentum of flywheel group, wherein:
For aerocraft system, because its attitude pace of change is slower, the characteristics that control cycle is short can be written as this formula: H
Wi=u
WiΔ t, Δ t are system's control cycle of aircraft, so H
w=u
wΔ t.
Then angular momentum nargin index is combined with energy indexes, utilizes the weight coefficient optimization method, propose to optimize in batches index:
Wherein
ρ 1=diag (ρ
11ρ
12ρ
1n) be the energy weight coefficient of each flywheel,
ρ 2=diag (ρ
21ρ
22ρ
2n) be the angular momentum nargin weight coefficient of each flywheel.
Therefore, optimizing distribution method can be expressed as optimization problem in batches:
Then Lagrangian function is H=J+ λ (I
Tu
w-u
c), the formula that the embodies substitution Lagrangian function of each amount is obtained
H wherein
Ws=IH
Wm-H
W0, with Lagrangian function respectively to u
wAsk local derviation to obtain with λ:
Obtain after the arrangement:
(1) formula is launched and can be obtained:
To obtain in this formula substitution (2) formula
Therefore
To can obtain optimizing in batches the analytical expression of distribution method in λ substitution (3) formula:
In the following formula, Δ t is system's control cycle of aircraft.
Step 4: the choosing of weight coefficient; For the energy weight coefficient
ρ 1, for i flywheel, its energy weight coefficient is chosen for the ratio of output torque with the average of the output torque of last all flywheels of the moment of this flywheel of the moment, namely
And for initial time
ρ 1The unit's of being chosen for diagonal matrix, namely
ρ 1(t
0)=diag (11 ... 1)
N * nFor angular momentum nargin weight coefficient
ρ 2, for i flywheel, its angular momentum nargin weight coefficient was chosen for the ratio of average of angular momentum nargin of angular momentum nargin and all flywheels in last a period of time of this flywheel constantly, namely
And for initial time
ρ 2The unit's of being chosen for diagonal matrix, namely
ρ 2(t
0)=diag (11 ... 1)
N * n
This method is utilized the weight coefficient optimization method, take all factors into consideration system capacity consumption and each flywheel output nargin, give suitable weight coefficient for each according to the output nargin of energy consumption and each flywheel, in the process that moment is distributed, regulate weight coefficient, when consuming to reach the minimizing energy, prevent that flywheel is saturated, not only be conducive to improve flywheel and be fan-out capability but also fuel saving to a certain extent.
Embodiment:
1. set up the single shaft mathematical model of counteraction flyback moment distribution in batches.Suppose on certain axle of aircraft n counteraction flyback to be housed, then the installation matrix of this flywheel group can be written as
System is expressed as u to this expectation moment
c, the instruction moment that each divided flywheel is fitted on is designated as
Then expect to satisfy u between the moment and instruction moment
c=I
Tu
w, this formula also is the constraint condition of differentiate optimization problem simultaneously.
2. the energy-optimised distribution method of deriving.Because the energy consumption of flywheel system and the output torque of each counteraction flyback are closely bound up, therefore, utilize the flywheel moment vector to be constructed as follows the energy indexes function
Then energy-optimised allocation strategy can be expressed as following optimization problem:
Adopt method of Lagrange multipliers structure Lagrangian function to be
With Lagrangian function respectively to u
wAsk local derviation can draw following formula with λ,
Obtain after the arrangement:
Simultaneous can obtain single shaft counteraction flyback moment optimization allocation strategy in batches, that is:
3. in conjunction with the concept of angular momentum nargin, derive and optimize distribution method in batches.The angular momentum initial value of supposing flywheel system is H
W0=[H
W01H
W02H
W0n], the angular momentum nargin vector that then defines the flywheel group is
H wherein
WmBe the maximum angular momentum that flywheel can reach, H
w=[H
W1H
W2H
Wn] be the output angle momentum of flywheel group, wherein:
For aerocraft system, because its attitude pace of change is slower, the characteristics that control cycle is short can be written as this formula: H
Wi=u
WiΔ t, Δ t are system's control cycle of aircraft.
Then angular momentum nargin index is combined with energy indexes, utilizes the weight coefficient optimization method, propose to optimize in batches index:
Wherein
ρ 1=diag (ρ
11ρ
12ρ
1n) be the energy weight coefficient of each flywheel,
ρ 2=diag (ρ
21ρ
22ρ
2n) be the angular momentum nargin weight coefficient of each flywheel.
Therefore, optimizing distribution method can be expressed as optimization problem in batches:
Then Lagrangian function is H=J+ λ (I
Tu
w-u
c), the formula that the embodies substitution Lagrangian function of each amount is obtained
H wherein
Ws=IH
Wm-H
W0, with Lagrangian function respectively to u
wAsk local derviation to obtain with λ:
Obtain after the arrangement:
(4) formula is launched and can be obtained:
To obtain in this formula substitution (5) formula
Therefore
To can obtain optimizing in batches the analytical expression of distribution method in λ substitution (6) formula:
In the formula
Δ t gets system's control cycle.
4. weight coefficient chooses; For the energy weight coefficient
ρ 1, for i flywheel, its energy weight coefficient is chosen for the ratio of output torque with the average of the output torque of last all flywheels of the moment of this flywheel of the moment, namely
And for initial time
ρ 1The unit's of being chosen for diagonal matrix, namely
ρ 1(t
0)=diag (11 ... 1)
N * nFor angular momentum nargin weight coefficient
ρ 2, for i flywheel, its angular momentum nargin weight coefficient was chosen for the ratio of average of angular momentum nargin of angular momentum nargin and all flywheels in last a period of time of this flywheel constantly, namely
And for initial time
ρ 2The unit's of being chosen for diagonal matrix, namely
ρ 2(t
0)=diag (11 ... 1)
N * n
So far, all variablees are known, can carry out moment to the batch flywheel and distribute.