CN105375716A - Position estimation method for electrical and mechanical conversion double-side switch magnetic resistance linear motor mover - Google Patents

Abstract

The invention relates to a position estimation method for an electrical and mechanical conversion double-side switch magnetic resistance linear motor mover. The method is suitable for estimating mover positions of double-side switch magnetic resistance linear motors having various phases, each phase of stator winding of a double-side switch magnetic resistance linear motor comprises four concentrated coils, each side stator respectively has two concentrated coils, the two concentrated coils on one side stator are connected in series to form a stator winding u, the two concentrated coils on the other side stator are connected in series to form a stator winding d, online detection on an inductance value of the stator winding u and an inductance value of the stator winding d is carried out, an overlapping distance value d of a stator pole and a mover pole of the double-side switch magnetic resistance linear motor is calculated, so the mover position is acquired, precision of the mover position is not influenced by an eccentric degree of the mover, a base is established for position-less sensor control on the double-side switch magnetic resistance linear motor, and wide application prospects can be realized.

Description

Energy converting between mechanical bilateral switched relutance linear motor rotor position estimating and measuring method

Technical field

The present invention relates to a kind of energy converting between mechanical bilateral switched relutance linear motor rotor position estimating and measuring method, be particularly useful for the bilateral switched relutance linear motor of the various number of phases.

Background technology

Switched reluctance machines wants enforcing location closed-loop control just can follow the operation of minimum reluctance principle, but traditional position transducer easily breaks down and lost efficacy, and it reduces the reliability of switched reluctance motor system.Serial of methods is proposed to switching magnetic-resistance electric rotary machine position Sensorless Control, its essence is identical, namely by applying excitation to winding, measure its electric current and anode-cathode voltage, derive phase inductance or magnetic linkage, utilize the mapping relations of rotor-position to inductance, magnetic linkage to draw rotor position information.Switched relutance linear motor can realize the mechanical energy of rectilinear motion and electric energy directly turns, without the need to intermediate conversion device or transmission mechanism, thus reduce the volume of linear motion system, weight and cost, and the multiple error such as power, speed that intermediate conversion or transmission link bring can be eliminated.The track caused due to motor processing technology and motor long-time running and bearing wear, often there is certain bias in double-flanged end switched relutance linear motor, adopt the traditional stator winding connection similar to switching magnetic-resistance electric rotary machine, to realize position Sensorless Control, owing to being subject to mover Influence from Eccentric, rotor position estimation precision is not high, is difficult to carry out effective double-flanged end switched relutance linear motor position Sensorless Control.Therefore, provide a kind of not by the bilateral switched relutance linear motor rotor position estimating and measuring method of mover Influence from Eccentric, very important to the effective double-flanged end switched relutance linear motor position Sensorless Control of enforcement.

Summary of the invention

The object of the invention is to have problems in prior art, energy converting between mechanical bilateral switched relutance linear motor rotor position estimating and measuring method that a kind of method simply, is not subject to mover Influence from Eccentric, that be applicable to the various number of phases is provided.

For achieving the above object, energy converting between mechanical of the present invention bilateral switched relutance linear motor rotor position estimating and measuring method, comprise and adopt bilateral switched relutance linear motor, two stators of bilateral switched relutance linear motor and a mover, two stators are located at the both sides of mover respectively, every phase stator winding of bilateral switched relutance linear motor is made up of 4 concentrating coils, both sides stator respectively there are 2 concentrating coils, by two concentrating coils stator winding u in series on the stator of described side, two concentrating coils stator winding d in series on opposite side stator, the inductance value of setting stator winding u is L _u, stator winding d inductance value be L _d, on-line checkingi inductance value L _uwith inductance value L _d, the overlap distance value d of bilateral switched relutance linear motor stator poles and mover pole is calculated by following formula:

$\frac{1}{L_u}+\frac{1}{L_d}=\frac{g_0}{{\mathrm{\μ}}_0{\mathrm{dLN}}^2}$

In formula: μ ₀for permeability of vacuum value, L is that bilateral switched relutance linear motor folds thick value, g ₀for the one-sided gas length value of bilateral switched relutance linear motor, N is the number of turn value of each concentrating coil on stator;

According to the overlap distance value d of the bilateral switched relutance linear motor stator poles obtained and mover pole, obtain bilateral switched relutance linear motor rotor position estimated value x by following formula:

x＝d+0.5Wms-0.5Wsp

In formula: Wsp is stator tooth width values, Wms is mover groove width value, rotor position when x=0 represents that stator poles center line aligns with mover groove center line.

Described electric mover is in uninfluenced situation, and its mover side gas length value is worth identical with opposite side gas length, is one-sided gas length value g ₀.

Beneficial effect: owing to have employed technique scheme, the present invention obtains the overlap distance value of bilateral switched relutance linear motor stator poles and mover pole by bilateral switched relutance linear motor both sides stator winding inductance value Reciprocals sums, again by the overlap distance value of bilateral switched relutance linear motor stator poles and mover pole, stator poles width values and mover groove width value, obtain bilateral switched relutance linear motor rotor position value, not by mover Influence from Eccentric, bilateral switched relutance linear motor rotor position estimation accurately, for bilateral switched relutance linear motor position Sensorless Control lays the foundation, be applicable to the bilateral switched relutance linear motor rotor position estimation of energy converting between mechanical of the various number of phases.Its method is simple, effective, has broad application prospects.

Accompanying drawing explanation

Fig. 1 is bilateral switched relutance linear motor stator winding coil connection diagram of the present invention.

Fig. 2 is that bilateral switched relutance linear motor one of the present invention communicates electrical equivalent magnetic circuit schematic diagram.

Fig. 3 is rotor position value of the present invention and stator poles and mover pole overlap distance value relation schematic diagram.

Fig. 4 is bilateral switched relutance linear motor power converter circuit topological structure schematic diagram of the present invention.

Embodiment

Below in conjunction with accompanying drawing, one embodiment of the present of invention are further described:

As shown in Figure 1, energy converting between mechanical of the present invention bilateral switched relutance linear motor rotor position estimating and measuring method, adopt bilateral switched relutance linear motor, two stators of bilateral switched relutance linear motor and a mover, two stators are located at the both sides of mover respectively, every phase stator winding of bilateral switched relutance linear motor is made up of 4 concentrating coils, both sides stator respectively there are 2 concentrating coils, by two concentrating coils stator winding u in series on the stator of described side, two concentrating coils stator winding d in series on opposite side stator, the inductance value of setting stator winding u is L _u, stator winding d inductance value be L _d, on-line checkingi inductance value L _uwith inductance value L _d, the overlap distance value d of bilateral switched relutance linear motor stator poles and mover pole is calculated by following formula:

$\frac{1}{L_u}+\frac{1}{L_d}=\frac{g_0}{{\mathrm{\μ}}_0{\mathrm{dLN}}^2}$

In formula: μ ₀for permeability of vacuum value, L is that bilateral switched relutance linear motor folds thick value, g ₀for the one-sided gas length value of bilateral switched relutance linear motor, in the uninfluenced situation of electric mover, electric mover side gas length value is worth identical with opposite side gas length, is one-sided gas length value g ₀, N is the number of turn value of each concentrating coil on stator;

According to the overlap distance value d of the bilateral switched relutance linear motor stator poles obtained and mover pole, obtain bilateral switched relutance linear motor rotor position estimated value x by following formula:

x＝d+0.5Wms-0.5Wsp

In formula: Wsp is stator tooth width values, Wms is mover groove width value, rotor position when x=0 represents that stator poles center line aligns with mover groove center line.

For the A phase of motor, A phase winding is by winding A ₁~ A ₄composition, side stator two winding A ₁and A ₂be connected in series and form side stator winding A _u, equally, opposite side stator A ₃and A ₄be connected in series and form opposite side side stator winding A _d;

For the B phase of motor, B phase winding is by winding B ₁~ B ₄composition, side stator two winding B ₁and B ₂be connected in series and form side stator winding B _u, equally, opposite side stator B ₃and B ₄be connected in series and form opposite side side stator winding B _d;

For the C phase of motor, C phase winding is by winding C ₁~ C ₄composition, side stator two winding C ₁and C ₂be connected in series and form side stator winding C _u, equally, opposite side stator C ₃and C ₄be connected in series and form opposite side side stator winding C _d;

For the B phase of motor, its equivalent magnetic circuit as shown in Figure 2, R _sfor stator core magnetic resistance value, R _ufor side air-gap reluctance value, R _dfor opposite side air-gap reluctance value, R _mfor mover core magnetic resistance value, and

$R_u=\frac{g_u}{{\mathrm{\μ}}_0{A}_g}=\frac{g_0(1\±\mathrm{\ϵ})}{{\mathrm{\μ}}_0\left(dL\right)}---\left(1\right)$

In formula: μ ₀permeability of vacuum value, A _gair gap equivalence magnetic flux area value, g _ufor side gas length value, g _dfor opposite side gas length value, in the not eccentric situation of electric mover, the gas length value of mover side is worth identical with opposite side gas length, is g ₀, L is that bilateral switched relutance linear motor folds thick value, and d is the overlap distance value of bilateral switched relutance linear motor stator poles and mover pole, and as shown in Figure 3, ε is mover eccentricity, namely

$\mathrm{\ϵ}=\frac{\mathrm{\Δ}g}{g_0}\×100\%---\left(3\right)$

In formula: Δ g is mover center displacement value.

Because air-gap reluctance value is much larger than stator, mover core magnetic resistance value, therefore ignore R in magnetic circuit _mand R _simpact, as shown in Figure 2; Between measuring point a and measuring point b approximate " short circuit ", whole magnetic circuit be divided into two independently magnetic circuit analyze, the Ni in Fig. 2 _uside stator winding coil B ₁and B ₂magnetic potential, Ni _dopposite side stator winding coil B ₃and B ₄magnetic potential.

In Fig. 2 loop 1, total magnetic resistance drawn by following formula:

$R_{tot}^u=2R_u+R_s+R_m\≈2R_u---\left(4\right)$

By coil B ₁with coil B ₂series connection, the side stator winding B connected into _uinductance value L _uapproximate calculation is

$L_u=\frac{{\left(2N\right)}^2}{R_{tot}^u}=\frac{{\left(2N\right)}^2}{2R_u}=\frac{2{\mathrm{\μ}}_0{\mathrm{dLN}}^2}{g_0(1\±\mathrm{\ϵ})}---\left(5\right)$

In formula: N is the number of turn value of each concentrating coil on stator.

In like manner, in Fig. 2 loop 2, opposite side stator winding B _dinductance value L _dapproximate calculation is:

Drawn by formula (5) and formula (6):

$\frac{1}{L_u}+\frac{1}{L_d}=\frac{g_0}{{\mathrm{\μ}}_0{\mathrm{dLN}}^2}---\left(7\right)$

Bilateral switched relutance linear motor both sides stator winding B _uand B _dinductance Reciprocals sums and bilateral switched relutance linear motor mover eccentricity have nothing to do, have one-to-one relationship with the overlap distance value d of bilateral switched relutance linear motor stator poles and mover pole;

As long as detect inductance value L _uwith inductance value L _djust can calculate overlap distance value d by formula (7).

Work as x=0, then represent rotor position when stator poles center line aligns with mover groove center line, bilateral switched relutance linear motor rotor position value x, Wsp are stator poles width values, Wms is mover groove width value, the overlap distance value d of stator poles and mover pole, can obtain bilateral switched relutance linear motor rotor position estimated value x by following formula:

x＝d+0.5Wms-0.5Wsp(8)

As shown in Figure 4, with power inverter, bilateral switched relutance linear motor stator winding is powered, A phase main switch S _a1, S _a2and S _a0conducting, sustained diode _a1, D _a2and D _a0turn off, A phase winding excitation, current path as shown in FIG., A _uand A _da phase both sides stator winding respectively; B phase main switch S _b1and S _b2shutoff, S _b0conducting, sustained diode _b1and D _b2conducting, D _b0turn off, the afterflow of B phase winding no-voltage, current path as shown in FIG., B _uand B _db phase both sides stator winding respectively; C phase main switch S _c1, S _c2and S _c0turn off, sustained diode _c1, D _c2and D _c0conducting, C phase winding negative voltage freewheel current path as shown in FIG., C _uand C _dc phase both sides stator winding respectively.

By controlling main switch turn-on and turn-off, high-frequency pulse voltage is injected mutually to non-conduction, non-conduction phase winding is allowed to experience excitation, no-voltage afterflow, negative voltage freewheeling period, by institute's response impulse current amplitude and pulse current rising and falling time in the stator winding of each phase both sides, calculate the inductance value L of both sides stator winding _uand L _d, more bilateral switched relutance linear motor rotor position estimated value x can be obtained, not by mover Influence from Eccentric by formula (7) and formula (8) calculating.

Claims (2)

1. an energy converting between mechanical bilateral switched relutance linear motor rotor position estimating and measuring method, comprise and adopt bilateral switched relutance linear motor, two stators of bilateral switched relutance linear motor and a mover, two stators are located at the both sides of mover respectively, every phase stator winding of bilateral switched relutance linear motor is made up of 4 concentrating coils, both sides stator respectively there are 2 concentrating coils, it is characterized in that: by two concentrating coils stator winding u in series on the stator of described side, two concentrating coils stator winding d in series on opposite side stator, the inductance value of setting stator winding u is L _u, stator winding d inductance value be L _d, on-line checkingi inductance value L _uwith inductance value L _d, the overlap distance value d of bilateral switched relutance linear motor stator poles and mover pole is calculated by following formula:

$\frac{1}{L_u}+\frac{1}{L_d}=\frac{g_0}{{\mathrm{\μ}}_0{\mathrm{dLN}}^2}$

In formula: μ ₀for permeability of vacuum value, L is that bilateral switched relutance linear motor folds thick value, g ₀for the one-sided gas length value of bilateral switched relutance linear motor, N is the number of turn value of each concentrating coil on stator;

According to the overlap distance value d of the bilateral switched relutance linear motor stator poles obtained and mover pole, obtain bilateral switched relutance linear motor rotor position estimated value x by following formula:

x＝d+0.5Wms-0.5Wsp

In formula: Wsp is stator tooth width values, Wms is mover groove width value, rotor position when x=0 represents that stator poles center line aligns with mover groove center line.

2. a kind of energy converting between mechanical according to claim 1 bilateral switched relutance linear motor rotor position estimating and measuring method, it is characterized in that: described electric mover is in uninfluenced situation, its mover side gas length value is worth identical with opposite side gas length, is one-sided gas length value g ₀.