CN103166329B - Bifurcation frequency transfer control circuit in inductive power transfer (IPT) system and control method thereof - Google Patents

Abstract

The invention discloses a bifurcation frequency transfer control circuit in an inductive power transfer (IPT) system and a control method of the bifurcation frequency transfer control circuit. The bifurcation frequency transfer control circuit comprises a power module, a switching network, a primary side resonance compensating circuit, a transmitting coil, a receiving coil, a secondary side resonance compensating circuit and loads. The bifurcation frequency transfer control circuit is characterized in that a delayed interference module is connected on a controller, and the controller controls the working condition of the switching network according to a delayed interference signal output by the delayed interference module and a zero-cross signal output by a zero-cross detection circuit. The bifurcation frequency transfer control circuit has the advantages of being simple in circuit structure, convenient to control and free of the requirement for addition of excessive circuits on a main circuit. Only timely delayed interference needs to be added on a detection feedback signal. According to design of the bifurcation frequency transfer control circuit in the IPT system and the specific control method of the bifurcation frequency transfer control circuit, phase track flow of the IPT system can be restrained to a specified stable attractor of a limit cycle, and therefore stability and reliability of the IPT system are improved.

Description

Fork frequency pipage control circuit and control method thereof in IPT system

Technical field

The present invention relates to induction electric energy transmission technology (Inductive Power Transfer is called for short IPT), specifically, is fork frequency pipage control circuit and the control method thereof in a kind of IPT system.

Background technology

Induction electric energy transmission technology (Inductive Power Transfer is called for short IPT) is that one take electromagnetic field of high frequency as energy carrier, electric energy is wirelessly transmitted to the delivery of electrical energy new technology of load end from power end with the form of magnetic energy.This technology has the advantages such as safe, reliable and flexible, has a wide range of applications in fields such as biology doctor electricity, track traffic, electric automobile, consumer electronics, has become one of study hotspot of field of power electronics.

As shown in Figure 1, from system configuration, IPT system comprises former limit and two parts of secondary, and former limit produces high-frequency alternating electric current on transmitting coil by controlled resonant converter, and the electric energy sensing on secondary energy receiving coil is exported to load after reactive power compensation and energy conversion.The particularity of structure and complexity cause system to present typical high-order nonlinear characteristic, thereby cause complicated dynamic behavior, have increased the difficulty of system modelling analysis and control.

Literature research shows, in IPT system, when system parameters is as mutual inductance, former secondary resonant network parameter and load impedance etc. change, all may cause the fork of system resonance frequency.In fork district, there are three resonance frequencys in the system that is presented as, wherein two have autonomous oscillatory stability, and another does not have autonomous oscillatory stability, and this frequency values is between two stabilized frequency values.About the research of non-contact electric energy transmission system frequency bifurcation can list of references " electrician's electric energy new technology " in April, 2005, the 24th disclosed paper of the 2nd phase of volume: the research of non-contact electric energy transmission system frequency bifurcation, author: electric institute of Xi'an Communications University, Han Teng, Zhuo Fang, etc.

In sum, the defect of prior art is: change to enter existing behind the frequency fork district that exceedes a stable resonant oscillation frequency with parameter in system, can work in which fork frequency actually, there is certain randomness, there is no at present way realize assigned frequency the phase path dynamic transport control of corresponding limit cycle attractor, thereby cause the problems such as system efficiency of transmission is unstable.

Summary of the invention

In order to overcome above-mentioned defect, the invention provides a kind of pipage control circuit and control method thereof of the frequency that diverges, for each resonant frequency point, its pipage control parameter is set respectively, then can as operation television set zapping, controls IPT system and freely switch on its multiple stable resonant oscillation Frequency points.

To achieve these goals, concrete technical scheme of the present invention is as follows:

Fork frequency pipage control circuit in a kind of IPT system, comprise power module, switching network, former limit resonance compensation circuit, transmitting coil, receiving coil, secondary resonance compensation circuit and load, its key is: on the resonance compensation circuit of described former limit, be connected with zero cross detection circuit, the output of this zero cross detection circuit is connected with controller, the output of this controller is connected with described switching network through overdrive circuit, on described controller, be also connected with time delay interference module, described controller is according to the operating state of switching network described in the zero cross signal control of the time delay interference signal of time delay interference module output and zero cross detection circuit output.

In conjunction with said system structure, the present invention also proposes the control method of the fork frequency pipage control circuit in a kind of IPT system, specifically carries out according to following steps:

Step 1: two stable fork frequencies determining IPT system are f ₁and f ₂, and f ₁< f ₂;

Step 2: two kinds of time delay interference signals are set, are respectively the first time delay interference signal (δ ₁, T _d1) and the second time delay interference signal (δ ₂, T _d2), wherein δ ₁be the first time delay interference signal delay time and t _d1be the duration of the first time delay interference signal, δ ₂be the second time delay interference signal delay time and t _d2it is the duration of the second time delay interference signal.

Step 3: if IPT system need to be from stable fork frequency f ₁control to f ₂time, export the first time delay interference signal (δ by described time delay interference module ₁, T _d1) in described controller; If IPT system need to be from stable fork frequency f ₂control to f ₁time, export the second time delay interference signal (δ by described time delay interference module ₂, T _d2) in described controller;

Step 4: do the used time in state no interference signal, the zero cross signal of the control signal of described controller output and the output of described zero cross detection circuit is with frequency homophase;

When controller receives the first time delay interference signal (δ ₁, T _d1) time, the control signal of output is described zero cross signal hysteresis δ ₁the signal of time span, and the duration of time delay interference effect be T _d1, work as duration T _d1when end, described control signal reverts to described zero cross signal with frequency homophase again;

When controller receives the second time delay interference signal (δ ₂, T _d2) time, the control signal of output is described zero cross signal hysteresis δ ₂the signal of time span, and the duration of time delay interference effect be T _d2, work as duration T _d2when end, described control signal reverts to described zero cross signal with frequency homophase again.

As further describing, in the time that former limit resonance compensation circuit (3) and secondary resonance compensation circuit (4) are series resonant tank, determine in accordance with the following steps two stable fork frequency f of IPT system ₁and f ₂:

Step 1-1: set up equation $\left\{\begin{array}{c}\mathrm{Px}*\left(T\right)=0\\ \mathrm{Pf}(\mathrm{\&tau;},x*)\&NotEqual;0,\mathrm{\&tau;}\&Element;(0,\frac{T}{2})\end{array}\right.,$ Wherein:

$\left\{\begin{array}{c}x*\left(T\right)={[I+\mathrm{\&Phi;}\left(\frac{T}{2}\right)]}^{-1}{[I-\mathrm{\&Phi;}\left(\frac{T}{2}\right)]A}^{-1}{\mathrm{BE}}_{\mathrm{dc}}\\ f(\mathrm{\&tau;},x*)=\mathrm{\&Phi;}\left(\mathrm{\&tau;}\right)x*+[\mathrm{\&Phi;}\left(\mathrm{\&tau;}\right)-I]A^{-1}{\mathrm{BE}}_{\mathrm{dc}}\\ \mathrm{\&Phi;}\left(t\right)=e^{\mathrm{At}}\end{array}\right.$

And P is projection matrix, A, B are coefficient of combination matrix, and I is and the unit matrix of A with exponent number, E _dcfor the output voltage of power module, x is system mode vector, and x* is the period fixed point of system mode vector x, and has:

x＝[i _p,u _p,i _s,u _s] ^T；

$A=\left[\begin{array}{cccc}\frac{L_S{R}_p}{M^2-L_p{L}_s}& \frac{L_s}{M^2-L_p{L}_s}& \frac{M(R_s+R_L)}{M^2-L_p{L}_s}& \frac{M}{M^2-L_p{L}_s}\\ \frac{1}{C_p}& 0& 0& 0\\ \frac{{\mathrm{MR}}_p}{M^2-L_p{L}_s}& \frac{M}{M^2-L_p{L}_s}& \frac{L_p(R_s+R_L)}{M^2-L_p{L}_s}& \frac{L_p}{M^2-L_p{L}_s}\\ 0& 0& \frac{1}{C_s}& 0\end{array}\right]$

$B={\left[\begin{array}{cccc}\frac{-L_S}{m^2-L_p{L}_s}& 0& \frac{-M}{M^2-L_p{L}_s}& 0\end{array}\right]}^T$

P＝[1?0?0?0]

Wherein, i _pfor former limit resonance current, u _pfor former limit resonance potential, i _sfor secondary resonance current, u _sfor secondary resonance potential, L _pfor the line of departure sense value of punctuating, R _pfor transmitting coil equivalent resistance, C _pfor former limit building-out capacitor value, L _sfor receiving coil inductance value, R _sfor receiving coil equivalent resistance, C _sfor secondary building-out capacitor value, R _lfor load resistance value, M is the mutual inductance value between transmitting coil and receiving coil;

Step 1-2: three roots that solve system fork region according to above-mentioned equation are T ₁, T', T ₂and T ₁> T'> T ₂;

Step 1-3: determine stable fork frequency according to three roots in step 1-2 $f_2=\frac{1}{T_2}.$

As preferably, the duration of described the first time delay interference signal the duration of described the second time delay interference signal

Remarkable result of the present invention is: circuit structure is simple, it is convenient to control, need on main circuit, not increase extra circuit, only need in detection feedback signal, add suitable time delay to disturb, by designing fork frequency pipage control circuit in this IPT system and the concrete control method of this circuit, system phase path stream can be converged on the stable limit cycle attractor of appointment, thereby improve stability and the reliability of IPT system.

Brief description of the drawings

Fig. 1 is the main circuit diagram that former and deputy limit is the IPT system of series resonance;

Fig. 2 is system principle diagram of the present invention;

Fig. 3 is control signal sequential chart of the present invention;

Fig. 4 is the system oscillation frequency response curve of specific embodiment.

Embodiment

Below in conjunction with accompanying drawing, the specific embodiment of the present invention and operation principle are described in further detail.

As Fig. 1, shown in Fig. 2, fork frequency pipage control circuit in a kind of IPT system, comprise power module 1, switching network 2, former limit resonance compensation circuit 3, transmitting coil, receiving coil, secondary resonance compensation circuit 4 and load, on described former limit resonance compensation circuit 3, be connected with zero cross detection circuit 5, mainly for detection of former limit resonance current i _pthe output of this zero cross detection circuit 5 is connected with controller 6, the output of this controller 6 is connected with described switching network 2 through overdrive circuit 7, on described controller 6, be also connected with time delay interference module 8, the operating state of switching network 2 described in the zero cross signal control that the time delay interference signal that described controller 6 is exported according to time delay interference module 8 and zero cross detection circuit 5 are exported.

In conjunction with foregoing circuit structure, the present invention also proposes the control method of the fork frequency pipage control circuit in a kind of described IPT system, specifically carries out according to following steps:

Step 1: two stable fork frequencies determining IPT system are f ₁and f ₂, and f ₁< f ₂;

Step 2: two kinds of time delay interference signals are set, are respectively the first time delay interference signal (δ ₁, T _d1) and the second time delay interference signal (δ ₂, T _d2), wherein δ ₁be the first time delay interference signal delay time and t _d1be the duration of the first time delay interference signal, δ ₂be the second time delay interference signal delay time and t _d2it is the duration of the second time delay interference signal.

Step 3: if IPT system need to be from stable fork frequency f ₁control to f ₂time, export the first time delay interference signal (δ by described time delay interference module 8 ₁, T _d1) in described controller 6; If IPT system need to be from stable fork frequency f ₂control to f ₁time, export the second time delay interference signal (δ by described time delay interference module 8 ₂, T _d2) in described controller 6;

Step 4: do the used time in state no interference signal, the zero cross signal that the control signal that described controller 6 is exported and described zero cross detection circuit 5 are exported is with frequency homophase;

When controller 6 receives the first time delay interference signal (δ ₁, T _d1) time, the control signal of output is described zero cross signal hysteresis δ ₁the signal of time span, and the duration of time delay interference effect be T _d1, work as duration T _d1when end, described control signal reverts to described zero cross signal with frequency homophase again;

When controller 6 receives the second time delay interference signal (δ ₂, T _d2) time, the control signal of output is described zero cross signal hysteresis δ ₂the signal of time span, and the duration of time delay interference effect be T _d2, work as duration T _d2when end, described control signal reverts to described zero cross signal with frequency homophase again.Shown in Fig. 3, can find out clearly the interference effect of time delay interference signal to control signal.

In specific implementation process, determine in accordance with the following steps two stable fork frequency f of IPT system ₁and f ₂, the IPT system that this example is only series resonant tank to the former limit resonance compensation circuit 3 shown in Fig. 1 and secondary resonance compensation circuit 4 is analyzed, and concrete steps are as follows:

Step 1-1: set up equation $\left\{\begin{array}{c}\mathrm{Px}*\left(T\right)=0\\ \mathrm{Pf}(\mathrm{\&tau;},x*)\&NotEqual;0,\mathrm{\&tau;}\&Element;(0,\frac{T}{2})\end{array}\right.,$ Wherein:

$\left\{\begin{array}{c}x*\left(T\right)={[I+\mathrm{\&Phi;}\left(\frac{T}{2}\right)]}^{-1}{[I-\mathrm{\&Phi;}\left(\frac{T}{2}\right)]A}^{-1}{\mathrm{BE}}_{\mathrm{dc}}\\ f(\mathrm{\&tau;},x*)=\mathrm{\&Phi;}\left(\mathrm{\&tau;}\right)x*+[\mathrm{\&Phi;}\left(\mathrm{\&tau;}\right)-I]A^{-1}{\mathrm{BE}}_{\mathrm{dc}}\\ \mathrm{\&Phi;}\left(t\right)=e^{\mathrm{At}}\end{array}\right.$

And P is projection matrix, A, B are coefficient of combination matrix, and I is and the unit matrix of A with exponent number, E _dcfor the output voltage of power module 1, x is system mode vector, and x* is the period fixed point of system mode vector x, and has:

x＝[i _p,u _p,i _s,u _s] ^T；

$A=\left[\begin{array}{cccc}\frac{L_S{R}_p}{M^2-L_p{L}_s}& \frac{L_s}{M^2-L_p{L}_s}& \frac{M(R_s+R_L)}{M^2-L_p{L}_s}& \frac{M}{M^2-L_p{L}_s}\\ \frac{1}{C_p}& 0& 0& 0\\ \frac{{\mathrm{MR}}_p}{M^2-L_p{L}_s}& \frac{M}{M^2-L_p{L}_s}& \frac{L_p(R_s+R_L)}{M^2-L_p{L}_s}& \frac{L_p}{M^2-L_p{L}_s}\\ 0& 0& \frac{1}{C_s}& 0\end{array}\right]$

$B={\left[\begin{array}{cccc}\frac{-L_S}{m^2-L_p{L}_s}& 0& \frac{-M}{M^2-L_p{L}_s}& 0\end{array}\right]}^T$

P＝[1?0?0?0]

Wherein, i _pfor former limit resonance current, u _pfor former limit resonance potential i _sfor secondary resonance current, u _sfor secondary resonance potential, L _pfor the line of departure sense value of punctuating, R _pfor transmitting coil equivalent resistance, C _pfor former limit building-out capacitor value, L _sfor receiving coil inductance value, R _sfor receiving coil equivalent resistance, C _sfor secondary building-out capacitor value, R _lfor load resistance value, M is the mutual inductance value between transmitting coil and receiving coil, for the voltage-type topological structure that former limit resonance compensation circuit 3 and secondary resonance compensation circuit 4 are other form, only need to change above-mentioned equation group, and each expression formula in coefficient of combination matrix A, B, other control step and operation principle are identical with the present embodiment;

Step 1-2: can solve system according to above-mentioned equation is T at three roots in fork region ₁, T', T ₂and T ₁> T'> T ₂, also can find out according to list of references listed in background technology, system is at three root T in fork region ₁, T', T ₂respectively corresponding two stabilized frequencies and an instability frequency, and instability frequency is between two stabilized frequencies;

Step 1-3: therefore can determine two stable fork frequencies according to three roots in step 1-2 $f_1=\frac{1}{T_1},$ $f_2=\frac{1}{T_2}.$

Because time delay interference signal duration span is wider, for guarantee system reenters another stable state from a stable state, as preferably, the duration of described the first time delay interference signal the duration of described the second time delay interference signal

In conjunction with a concrete IPT system, system parameters value is as shown in table 1, can be as shown in table 2 in the hope of the resonance working point of system according to the system equation group of this system buildup, can set the first time delay interference signal (δ according to the frequency values of two of table 2 gained stable fork Frequency points ₁, T _d1) delay time δ ₁be 15 μ s, duration time T _d1be made as 500 μ s, the second time delay interference signal (δ ₂, T _d2) delay time δ ₂be 5 μ s, duration T _d2be made as 500 μ s, according to above-mentioned parameter and control step, this IPT system controlled, can obtain the frequency of oscillation response curve shown in Fig. 4.

Analyze visible by Fig. 4, system startup enters after stable state, is operated on resonance point 3, and its autonomous oscillatory work frequency is 48.08kHz, when adding after time lag interference signal, system oscillation frequency generation marked change, by 48.08kHz rapid adjustment to 64.52kHz, after time lag end of interrupt, the autonomous frequency of oscillation of system converges to 63.25kHz, system works point is transferred on resonance point 1, and resonance frequency is controlled, ensures stability and the reliability of system.

Table 1 series resonance-type IPT system parameter table

Table 2 series resonance-type IPT system resonance working point

Claims (3)

1. the control method of the fork frequency pipage control circuit in an IPT system, its circuit comprises power module (1), switching network (2), former limit resonance compensation circuit (3), transmitting coil, receiving coil, secondary resonance compensation circuit (4) and load, on described former limit resonance compensation circuit (3), be connected with zero cross detection circuit (5), the output of this zero cross detection circuit (5) is connected with controller (6), the output of this controller (6) is connected with described switching network (2) through overdrive circuit (7), on described controller (6), be also connected with time delay interference module (8), it is characterized in that this circuit controls according to following steps:

Step 1: two stable fork frequencies determining IPT system are f ₁and f ₂, and f ₁< f ₂;

Step 2: two kinds of time delay interference signals are set, are respectively the first time delay interference signal (δ ₁, T _d1) and the second time delay interference signal (δ ₂, T _d2), wherein δ ₁be the first time delay interference signal delay time and t _d1be the duration of the first time delay interference signal, δ ₂be the second time delay interference signal delay time and t _d2it is the duration of the second time delay interference signal;

Step 3: if IPT system need to be from stable fork frequency f ₁control to f ₂time, by described time delay interference module (8) output the first time delay interference signal (δ ₁, T _d1) in described controller (6); If IPT system need to be from stable fork frequency f ₂control to f ₁time, by described time delay interference module (8) output the second time delay interference signal (δ ₂, T _d2) in described controller (6);

Step 4: do the used time in state no interference signal, the zero cross signal of the control signal of described controller (6) output and described zero cross detection circuit (5) output is with frequency homophase;

When controller (6) receives the first time delay interference signal (δ ₁, T _d1) time, the control signal of output is described zero cross signal hysteresis δ ₁the signal of time span, and the duration of time delay interference effect be T _d1, work as duration T _d1when end, described control signal reverts to described zero cross signal with frequency homophase again;

When controller (6) receives the second time delay interference signal (δ ₂, T _d2) time, the control signal of output is described zero cross signal hysteresis δ ₂the signal of time span, and the duration of time delay interference effect be T _d2, work as duration T _d2when end, described control signal reverts to described zero cross signal with frequency homophase again.

2. the control method of the fork frequency pipage control circuit in IPT system according to claim 1, it is characterized in that: in the time that former limit resonance compensation circuit (3) and secondary resonance compensation circuit (4) are series resonant tank, determine in accordance with the following steps two stable fork frequency f of IPT system ₁and f ₂:

Step 1-1: set up equation wherein:

And P is projection matrix, A, B are coefficient of combination matrix, and I is and the unit matrix of A with exponent number, E _dcfor the output voltage of power module (1), x is system mode vector, and x* is the period fixed point of system mode vector x, and has:

x＝[i _p,u _p,i _s,u _s] ^T；

P＝[1?0?0?0]

Wherein, i _pfor former limit resonance current, u _pfor former limit resonance potential, i _sfor secondary resonance current, u _sfor secondary resonance potential, L _pfor transmitting coil inductance value, R _pfor transmitting coil equivalent resistance, C _pfor former limit building-out capacitor value, L _sfor receiving coil inductance value, R _sfor receiving coil equivalent resistance, C _sfor secondary building-out capacitor value, R _lfor load resistance value, M is the mutual inductance value between transmitting coil and receiving coil;

Step 1-2: three roots that solve system fork region according to above-mentioned equation are T ₁, T', T ₂and T ₁> T'> T ₂;

Step 1-3: determine stable fork frequency according to three roots in step 1-2

3. the control method of the fork frequency pipage control circuit in IPT system according to claim 1, is characterized in that: the duration of described the first time delay interference signal the duration of described the second time delay interference signal