CN101582670A - Method for fixing turn-off angle and optimizing turn-on angle of switched reluctance generator - Google Patents

Abstract

The invention discloses a method for fixing a turn-off angle and optimizing a turn-on angle of a switched reluctance generator, and belongs to the technical field of switched reluctance generator control. The method comprises the following steps of: 1, firstly deducing a phase current expression according to a voltage equation of the switched reluctance generator, integrating based on the expression to evaluate an average electromagnetic power expression in a cycle, and isolating a factor only related to the turn-on angle and the turn-off angle from the expression; and 2, then fixing the turn-off angle, making the turn-on angle change in a reasonable range, taking the factor as a one-variable function of the turn-on angle, and solving the turn-on angle corresponding to the maximum value of the one-variable function according to the characteristic of higher derivative of the one-variable function. The method has the advantages of theoretical basis, simpleness and good commonality.

Description

The method of switch reluctance generator fixing turn-off angle and optimizing turn-on angle

Technical field

Invention relates to a kind of method of switch reluctance generator fixing turn-off angle and optimizing turn-on angle, belongs to the technical field of switch reluctance generator control.

Background technology

The control of switch reluctance generator is divided into three kinds usually: current chopping control, voltage pwm control and angle position control.

1. present, the research that Chinese scholars is controlled for the switch reluctance generator angle mainly concentrates on by emulation and optimum experimental and opens the shutoff angle to obtain on the peak power output, this optimization method relies on experience accumulation and practice, is theoretically unsound to a certain extent.

2. traditional angle optimization method need carry out repeatedly emulation and experiment obtains the result, the process complexity, and workload is big.

The conclusion of 3. traditional angle optimization method is only set up the motor object that carries out emulation and experiment, does not possess versatility, when the motor object changes, need carry out emulation and experiment again.

The result of 4. traditional angle optimization method changes with the variation of simulated conditions and experimental situation, and its precision is subjected to the restriction of emulation and experiment number.

Summary of the invention

The present invention seeks to provide a kind of method of switch reluctance generator fixing turn-off angle and optimizing turn-on angle at the defective that prior art exists.

The present invention adopts following technical scheme for achieving the above object:

The method of switch reluctance generator fixing turn-off angle and optimizing turn-on angle of the present invention is characterized in that comprising the steps:

1) the phase inductance L of the described switch reluctance generator of initialization and the pass angle of rupture;

2) rational turn-on angle increment Delta θ _OnThe ascent stage that makes turn-on angle be in the described phase inductance L of step 1 promptly satisfies: Δ θ _On∈ [θ ₂-θ ₄+ θ ₁, θ ₁], and make the phase magnetic linkage of switch reluctance generator drop to zero promptly satisfied at phase inductance L minimal segment: Δ θ _On∈ [2 θ ₃-θ ₆, 2 θ ₃-θ ₄], if above-mentioned two interval existence occur simultaneously, then the described pass of step 1 angle of rupture rationally enters step 3; Otherwise the condition of working as is 2 θ a) ₃-θ ₆＜θ ₂-θ ₄+ θ ₁And 2 θ ₃-θ ₄＜θ ₂-θ ₄+ θ ₁Or condition b) 2 θ ₃-θ ₆＞θ ₁, it is unreasonable then to close the angle of rupture, returns step 1 and reinitializes the pass angle of rupture, wherein θ ₁Be first deflection angle of phase inductance L, θ ₂Be second deflection angle of phase inductance L, θ ₄Be the 3rd deflection angle of phase inductance L, θ ₆Be the 4th deflection angle of phase inductance L, θ ₃Be the initialized pass angle of rupture, down together;

3) ask for turn-on angle increment Delta θ _OnSpan [X ₁, X ₂]:

Work as θ ₂-θ ₄+ θ ₁≤ 2 θ ₃-θ ₆≤ θ ₁And 2 θ ₃-θ ₄〉=θ ₁, Δ θ _OnSpan be:

Δθ _on∈[2θ ₃-θ ₆，θ ₁]；

Work as θ ₂-θ ₄+ θ ₁≤ 2 θ ₃-θ ₆≤ θ ₁And 2 θ ₃-θ ₄＜θ ₁, Δ θ _OnSpan be:

Δθ _on∈[2θ ₃-θ ₆，2θ ₃-θ ₄]；

As 2 θ ₃-θ ₆＜θ ₂-θ ₄+ θ ₁And θ ₂-θ ₄+ θ ₁≤ 2 θ ₃-θ ₄≤ θ ₁, Δ θ _OnSpan be:

Δθ _on∈[θ ₂-θ ₄+θ ₁，2θ ₃-θ ₄]；

As 2 θ ₃-θ ₆＜θ ₂-θ ₄+ θ ₁And 2 θ ₃-θ ₄＞θ ₁, Δ θ _OnSpan be:

Δθ _on∈[θ ₂-θ ₄+θ ₁，θ ₁]，

X wherein ₁Be turn-on angle increment Delta θ _OnThe left end point of span, X ₂Be turn-on angle increment Delta θ _OnThe right endpoint of span;

4) described switch reluctance generator is placed under the self-excitation pattern, obtains the average electrical magnetic power of a rotor cycle of switch reluctance generator: $P_{\mathrm{av}}=\frac{\mathrm{<figure-callout\; id="2"\; label="m\; U\; c"\; filenames="A2009100278400011H1.png,A2009100278400012H1.png"\; state="\{\{state\}\}">m</figure-callout>}{U}_c^{}{}_2^{}}{{2\mathrm{\&theta;}}_r\mathrm{K\&omega;}}F\left({\mathrm{\&Delta;\&theta;}}_{\mathrm{on}}\right),$ Wherein m is the number of phases of switched reluctance machines, θ _rBe the angle that the rotor one-period turns over, F () is an one-variable function, F (Δ θ _On) be turn-on angle increment Delta θ _OnOne-variable function, U _cBe the voltage at described switch reluctance generator generating electric capacity two ends, ω is a rotor velocity, and K is the absolute value of phase inductance L slope;

5) as F (X ₁) 〉=F (X ₂), then optimum turn-on angle increment θ=X ₁, otherwise optimum turn-on angle increment θ=X ₂

6) the described optimum turn-on angle increment θ of step 5 is converted into the coordinate system commonly used of switched reluctance machines, promptly rotor pole and stator slot axial alignment location definition are the optimum turn-on angle θ under the coordinate system of zero degree _On, ${\mathrm{\&theta;}}_{\mathrm{on}}=\frac{{\mathrm{\&theta;}}_r}{2}-\frac{{\mathrm{\&theta;}}_1}{2}-\frac{{\mathrm{\&theta;}}_2}{2}+\mathrm{\&theta;}.$

The inventive method has following characteristics: 1. the conclusion of this optimization method is based on theoretical derivation, and the optimization of opening angle for switch reluctance generator provides certain theoretical foundation; 2. this optimization method only need be imported initial condition and just can be need not to have significantly reduced workload by repeatedly emulation and experiment by the computer solving result; 3. this optimization method versatility is good, and for different switch reluctance generators, procedure subject is constant, only needs to change the initial condition of input, can draw corresponding conclusion.4. the result of this optimization method does not change with the variation of simulated conditions and experimental situation, and its precision is not subjected to the restriction of emulation and experiment number.

Generally speaking, the method for switch reluctance generator fixing turn-off angle and optimizing turn-on angle is a kind of based on theoretical derivation, and optimizing process is simple, the optimization method that versatility is good.

Description of drawings

Fig. 1 is a main flow chart of the present invention;

Fig. 2 is step 2 of the present invention, 3 flow charts;

Fig. 3 is the initialized variable schematic diagram of the present invention, number in the figure: θ ₁, θ ₂, θ ₄, θ ₆: be the form parameter of inductance; θ ₃: be the initialized pass angle of rupture; θ ₅: for magnetic linkage drops to zero pairing angle, under the self-excitation pattern, θ ₅=2 θ ₃L _Max: be the phase inductance maximum; K: be the absolute value of phase inductance slope, K=(L _Max-L _Min)/(θ ₄-θ ₂), L wherein _MinBe the phase inductance minimum value;

Fig. 4 is the described F of step 5 of the present invention (Δ θ _On) second dervative and turn-on angle increment Delta θ _OnThe intersection point D of axle and turn-on angle increment constant interval concern schematic diagram, D is forever on the left side of turn-on angle increment constant interval.

Embodiment

The method of the invention is divided into following steps: 1. initialization inductance parameters L _Max, K, θ ₁, θ ₂, θ ₄, θ ₆With pass angle of rupture θ ₃, notice that the origin of coordinates should be in the inductance ascent stage and the pass angle of rupture should be in inductance descending branch (seeing accompanying drawing 3).2. judge whether initialization is reasonable, reasonable then calculate the scope of turn-on angle increment, otherwise get back to step 1, and reinitializing, the flow process in this step is seen accompanying drawing 2.3. calculate F (X ₁), F (X ₂).4. find the solution the turn-on angle increment of maximum average electrical magnetic power correspondence.F (Δ θ _On) second dervative perseverance on the constant interval of turn-on angle increment just (see accompanying drawing 4), more interval two-end-point can be obtained optimum turn-on angle increment.5. the position of definition rotor pole and stator slot axial alignment is a zero degree, and the turn-on angle increment of trying to achieve is converted into the turn-on angle number of degrees under this definition.

Be elaborated below in conjunction with the technical scheme of accompanying drawing 1 to 4 pairs of inventions of accompanying drawing:

The method of switch reluctance generator fixing turn-off angle and optimizing turn-on angle of the present invention is characterized in that comprising the steps:

1) the phase inductance L of the described switch reluctance generator of initialization and the pass angle of rupture;

2) rational turn-on angle increment Delta θ _OnThe ascent stage that makes turn-on angle be in the described phase inductance L of step 1 promptly satisfies: Δ θ _On∈ [θ ₂-θ ₄+ θ ₁, θ ₁], and make the phase magnetic linkage of switch reluctance generator drop to zero promptly satisfied at phase inductance L minimal segment: Δ θ _On∈ [2 θ ₃-θ ₆, 2 θ ₃-θ ₄], if above-mentioned two interval existence occur simultaneously, then the described pass of step 1 angle of rupture rationally enters step 3; Otherwise the condition of working as is 2 θ a) ₃-θ ₆＜θ ₂-θ ₄+ θ ₁And 2 θ ₃-θ ₄＜θ ₂-θ ₄+ θ ₁Or condition b) 2 θ ₃-θ ₆＞θ ₁, it is unreasonable then to close the angle of rupture, returns step 1 and reinitializes the pass angle of rupture, wherein θ ₁Be first deflection angle of phase inductance L, θ ₂Be second deflection angle of phase inductance L, θ ₄Be the 3rd deflection angle of phase inductance L, θ ₆Be the 4th deflection angle of phase inductance L, θ ₃Be the initialized pass angle of rupture, down together;

3) ask for turn-on angle increment Delta θ _OnSpan [X ₁, X ₂]:

Work as θ ₂-θ ₄+ θ ₁≤ 2 θ ₃-θ ₆≤ θ ₁And 2 θ ₃-θ ₄〉=θ ₁, Δ θ _OnSpan be:

Δθ _on∈[2θ ₃-θ ₆，θ ₁]；

Work as θ ₂-θ ₄+ θ ₁≤ 2 θ ₃-θ ₆≤ θ ₁And 2 θ ₃-θ ₄＜θ ₁, Δ θ _OnSpan be:

Δθ _on∈[2θ ₃-θ ₆，2θ ₃-θ ₄]；

As 2 θ ₃-θ ₆＜θ ₂-θ ₄+ θ ₁And θ ₂-θ ₄+ θ ₁≤ 2 θ ₃-θ ₄≤ θ ₁, Δ θ _OnSpan be:

Δθ _on∈[θ ₂-θ ₄+θ ₁，2θ ₃-θ ₄]；

As 2 θ ₃-θ ₆＜θ ₂-θ ₄+ θ ₁And 2 θ ₃-θ ₄＞θ ₁, Δ θ _OnSpan be:

Δθ _on∈[θ ₂-θ ₄+θ ₁，θ ₁]，

X wherein ₁Be turn-on angle increment Delta θ _OnThe left end point of span, X ₂Be turn-on angle increment Delta θ _OnThe right endpoint of span;

4) described switch reluctance generator is placed under the self-excitation pattern, obtains the average electrical magnetic power of a rotor cycle of switch reluctance generator:

$P_{\mathrm{av}}=\frac{\mathrm{<figure-callout\; id="2"\; label="m\; U\; c"\; filenames="A2009100278400011H1.png,A2009100278400012H1.png"\; state="\{\{state\}\}">m</figure-callout>}{U}_c^{}{}_2^{}}{2{\mathrm{\&theta;}}_r\mathrm{K\&omega;}}\left[\begin{array}{c}{\mathrm{\&theta;}}_1+{\mathrm{\&theta;}}_2-{\mathrm{\&theta;}}_4+\frac{{\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="A2009100278400011H1.png,A2009100278400012H1.png"\; state="\{\{state\}\}">M</figure-callout>}}_1{\mathrm{\&theta;}}_1}{{\mathrm{\&theta;}}_1+{\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="A2009100278400011H1.png,A2009100278400012H1.png"\; state="\{\{state\}\}">M</figure-callout>}}_1}+\frac{{\mathrm{<figure-callout\; id="2"\; label="M"\; filenames="A2009100278400011H1.png,A2009100278400012H1.png"\; state="\{\{state\}\}">M</figure-callout>}}_2^2({\mathrm{\&theta;}}_2-{\mathrm{\&theta;}}_3)}{({\mathrm{\&theta;}}_3-M_2)({\mathrm{\&theta;}}_2-M_2)}+\frac{{(M_2-{2\mathrm{\&theta;}}_3)}^2({\mathrm{\&theta;}}_3-{\mathrm{\&theta;}}_4)}{({\mathrm{\&theta;}}_4-M_2)({\mathrm{\&theta;}}_3-M_2)}\\ -{2\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="A2009100278400011H1.png,A2009100278400012H1.png"\; state="\{\{state\}\}">M</figure-callout>}}_1\ln \left(\frac{{\mathrm{\&theta;}}_1+M_1}{M_1}\right)-{2\mathrm{<figure-callout\; id="2"\; label="M"\; filenames="A2009100278400011H1.png,A2009100278400012H1.png"\; state="\{\{state\}\}">M</figure-callout>}}_2\ln \left(\frac{{\mathrm{\&theta;}}_3-{\mathrm{<figure-callout\; id="2"\; label="M"\; filenames="A2009100278400011H1.png,A2009100278400012H1.png"\; state="\{\{state\}\}">M</figure-callout>}}_2}{{\mathrm{\&theta;}}_2-M_2}\right)-2(M_2-{2\mathrm{\&theta;}}_3)\ln \left(\frac{{\mathrm{\&theta;}}_4-{\mathrm{<figure-callout\; id="2"\; label="M"\; filenames="A2009100278400011H1.png,A2009100278400012H1.png"\; state="\{\{state\}\}">M</figure-callout>}}_2}{{\mathrm{\&theta;}}_3-M_2}\right)\end{array}\right],$

M wherein ₁=L _Max/ K-θ ₁, M ₂=L _Max/ K+ θ ₂, θ ₃Be the initialized pass angle of rupture, m is the number of phases of switched reluctance machines, θ _rBe the angle that the rotor one-period turns over, U _cBe the voltage at described switch reluctance generator generating electric capacity two ends, ω is a rotor velocity, and K is the absolute value of phase inductance L slope.Formula that the following formula bracket is outer and turn-on angle are irrelevant, all θ in the formula in the bracket _nItem (θ _n-Δ θ _On) replace n=1 wherein, 2,3,4, Δ θ _OnBe the turn-on angle increment, and its abbreviation got:

$F\left({\mathrm{\&Delta;\&theta;}}_{\mathrm{on}}\right)=C+\frac{{{\mathrm{\&Delta;\&theta;}}_{\mathrm{on}}}^2}{M_2-{\mathrm{\&theta;}}_4}+{\mathrm{<figure-callout\; id="1"\; label="K"\; filenames="A2009100278400011H1.png,A2009100278400012H1.png"\; state="\{\{state\}\}">K</figure-callout>}}_1{\mathrm{\&Delta;\&theta;}}_{\mathrm{on}}+2({\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="A2009100278400011H1.png,A2009100278400012H1.png"\; state="\{\{state\}\}">M</figure-callout>}}_1+{\mathrm{\&Delta;\&theta;}}_{\mathrm{on}})\ln \frac{{\mathrm{\&theta;}}_1+M_1}{{\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="A2009100278400011H1.png,A2009100278400012H1.png"\; state="\{\{state\}\}">M</figure-callout>}}_1+{\mathrm{\&Delta;\&theta;}}_{\mathrm{on}}},$

Wherein ${\mathrm{<figure-callout\; id="1"\; label="K"\; filenames="A2009100278400011H1.png,A2009100278400012H1.png"\; state="\{\{state\}\}">K</figure-callout>}}_1=\frac{{2\mathrm{KM}}_1({\mathrm{\&theta;}}_3-M_2)+2{\mathrm{KM}}_2({\mathrm{\&theta;}}_3-{\mathrm{\&theta;}}_2)}{L_{\max }({\mathrm{\&theta;}}_3-M_2)}+\frac{2({\mathrm{\&theta;}}_4-{\mathrm{\&theta;}}_3)(M_2-{2\mathrm{\&theta;}}_3)}{({\mathrm{\&theta;}}_3-M_2)({\mathrm{\&theta;}}_4-M_2)}+2\ln \frac{({\mathrm{\&theta;}}_4-M_2)({\mathrm{\&theta;}}_2-M_2)}{{({\mathrm{\&theta;}}_3-M_2)}^2},$

C is and Δ θ _OnIrrelevant constant,

Ask second dervative to get: $F^{\&prime;\&prime;}\left({\mathrm{\&Delta;\&theta;}}_{\mathrm{on}}\right)=\frac{2}{M_2-{\mathrm{\&theta;}}_4}-\frac{2}{{\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="A2009100278400011H1.png,A2009100278400012H1.png"\; state="\{\{state\}\}">M</figure-callout>}}_1+{\mathrm{\&Delta;\&theta;}}_{\mathrm{on}}},$

This function is that the right half point that moves on two four-quadrant hyperbolas move to left again earlier props up.It and Δ θ _OnThe axle intersection point is:

D＝θ ₁+θ ₂-θ ₄。

5) as F (X ₁) 〉=F (X ₂), then optimum turn-on angle increment θ=X ₁, otherwise optimum turn-on angle increment θ=X ₂

6) the described optimum turn-on angle increment θ of step 5 is converted into the coordinate system commonly used of switched reluctance machines, promptly rotor pole and stator slot axial alignment location definition are the optimum turn-on angle θ under the coordinate system of zero degree _On, ${\mathrm{\&theta;}}_{\mathrm{on}}=\frac{{\mathrm{\&theta;}}_r}{2}-\frac{{\mathrm{\&theta;}}_1}{2}-\frac{{\mathrm{\&theta;}}_2}{2}+\mathrm{\&theta;}.$

Operation principle of the present invention is that the phase winding voltage equation that adopts separation of variables to find the solution switch reluctance generator obtains instantaneous phase current expression formula, and then obtain the transient electromagnetic power expression, by can draw the average electrical magnetic power expression formula of a rotor cycle to transient electromagnetic power integration.Factor only relevant with opening the pass angle of rupture in the average electrical magnetic power expression formula is separated independent research, if the fixing angle of rupture that closes, it is the one-variable function of turn-on angle increment so.According to the permanent positive characteristic of its second dervative, more interval two-end-point draws optimum turn-on angle increment, and then draws optimum turn-on angle.

Claims (1)

1, a kind of method of switch reluctance generator fixing turn-off angle and optimizing turn-on angle is characterized in that comprising the steps:

1) the phase inductance L of the described switch reluctance generator of initialization and the pass angle of rupture;

2) rational turn-on angle increment Delta θ _OnThe ascent stage that makes turn-on angle be in the described phase inductance L of step 1 promptly satisfies: Δ θ _On∈ [θ ₂-θ ₄+ θ ₁, θ ₁], and make the phase magnetic linkage of switch reluctance generator drop to zero promptly satisfied at phase inductance L minimal segment: Δ θ _On∈ [2 θ ₃-θ ₆, 2 θ ₃-θ ₄], if above-mentioned two interval existence occur simultaneously, then the described pass of step 1 angle of rupture rationally enters step 3; Otherwise the condition of working as is 2 θ a) ₃-θ ₆＜θ ₂-θ ₄+ θ ₁And 2 θ ₃-θ ₄＜θ ₂-θ ₄+ θ ₁Or condition b) 2 θ ₃-θ ₆＞θ ₁, it is unreasonable then to close the angle of rupture, returns step 1 and reinitializes the pass angle of rupture, wherein θ ₁Be first deflection angle of phase inductance L, θ ₂Be second deflection angle of phase inductance L, θ ₄Be the 3rd deflection angle of phase inductance L, θ ₆Be the 4th deflection angle of phase inductance L, θ ₃Be the initialized pass angle of rupture, down together;

3) ask for turn-on angle increment Delta θ _OnSpan [X ₁, X ₂]:

Work as θ ₂-θ ₄+ θ ₁≤ 2 θ ₃-θ ₆≤ θ ₁And 2 θ ₃-θ ₄〉=θ ₁, Δ θ _OnSpan be:

Δθ _on∈[2θ ₃-θ ₆，θ ₁]；

Work as θ ₂-θ ₄+ θ ₁≤ 2 θ ₃-θ ₆≤ θ ₁And 2 θ ₃-θ ₄＜θ ₁, Δ θ _OnSpan be:

Δθ _on∈[2θ ₃-θ ₆，2θ ₃-θ ₄]；

As 2 θ ₃-θ ₆＜θ ₂-θ ₄+ θ ₁And θ ₂-θ ₄+ θ ₁≤ 2 θ ₃-θ ₄≤ θ ₁, Δ θ _OnSpan be:

Δθ _on∈[θ ₂-θ ₄+θ ₁，2θ ₃-θ ₄]；

As 2 θ ₃-θ ₆＜θ ₂-θ ₄+ θ ₁And 2 θ ₃-θ ₄＞θ ₁, Δ θ _OnSpan be:

Δθ _on∈[θ ₂-θ ₄+θ ₁，θ ₁]，

X wherein ₁Be turn-on angle increment Delta θ _OnThe left end point of span, X ₂Be turn-on angle increment Delta θ _OnThe right endpoint of span;

4) described switch reluctance generator is placed under the self-excitation pattern, obtains the average electrical magnetic power of a rotor cycle of switch reluctance generator: $P_{\mathrm{av}}=\frac{m{U}_c^2}{2{\mathrm{\&theta;}}_r\mathrm{K\&omega;}}F\left({\mathrm{\&Delta;\&theta;}}_{\mathrm{on}}\right),$ Wherein m is the number of phases of switched reluctance machines, θ _rBe the angle that the rotor one-period turns over, F () is an one-variable function, F (Δ θ _On) be turn-on angle increment Delta θ _OnOne-variable function, U _cBe the voltage at described switch reluctance generator generating electric capacity two ends, ω is a rotor velocity, and K is the absolute value of phase inductance L slope;

5) as F (X ₁) 〉=F (X ₂), then optimum turn-on angle increment θ=X ₁, otherwise optimum turn-on angle increment θ=X ₂

6) the described optimum turn-on angle increment θ of step 5 is converted into the coordinate system commonly used of switched reluctance machines, promptly rotor pole and stator slot axial alignment location definition are the optimum turn-on angle θ under the coordinate system of zero degree _On, ${\mathrm{\&theta;}}_{\mathrm{on}}=\frac{{\mathrm{\&theta;}}_r}{2}-\frac{{\mathrm{\&theta;}}_1}{2}-\frac{{\mathrm{\&theta;}}_2}{2}+\mathrm{\&theta;}.$

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