CN105958664A - Power efficiency optimization method for wireless electric energy transmission system based on maximum power matching - Google Patents

Abstract

The invention discloses a power efficiency optimization method for a wireless electric energy transmission system based on maximum power matching, and the method achieves the joint optimization of power and efficiency under the condition of achieving the power matching of the wireless electric energy transmission system. Aiming at a wireless electric energy transmission system which requires for a medium transmission distance and the transmitting side and receiving side parameters of which cannot be changed, the method generates a plurality of matching power points and efficiency points corresponding to the matching power points when a fixed load is connected. According to the load demands, the proper power and efficiency points are selected from the plurality of generated matching power points and corresponding efficiency points as the working points of the system. The method meets the demands of the load for the power, and optimizes the efficiency and power on the basis.

Description

A kind of radio energy transmission system power efficiency optimization method based on peak power coupling

Technical field

The present invention relates to a kind of method that radio energy transmission system power efficiency optimizes, it is adaptable to distance radio in meter level Can transmit, not change transmitting terminal and the radio energy transmission system of receiving terminal parameter simultaneously.

Background technology

At middle distance wireless power transmission technological layer, how to optimize bearing power and efficiency of transmission always is a research Hot issue.At present, in order to realize at distance occasion relatively high power and the electric energy wireless transmission of greater efficiency, first, The resonant frequency of system is the highest, up to several MHz～tens MHz；Second, the resonance line that design size is bigger Circle improves transmission performance；3rd, optimize systematic parameter to realize the impedance matching of system.But, at higher resonance Under frequency, high frequency electric source is difficult to the output of relatively high power, and the most too high resonant frequency not only reduces the steady of system Localization degree, and the requirement for device is the highest.By the method for the resonance coil of design large-size at transmission sky Between cannot apply under limited occasion.About being realized the optimization of bearing power and system effectiveness by impedance matching, then study More, but be limited to emitting side or receive side be controlled and optimize.Emitting side and receive side the most restricted and not When just changing, these methods have just lacked the possibility of application.

Summary of the invention

Goal of the invention: in order to overcome the deficiency of existing scheme, the present invention proposes a kind of based on peak power coupling wireless Electric energy transmission system power efficiency optimization method.

Technical scheme: a kind of radio energy transmission system power efficiency optimization method based on peak power coupling, described nothing Line electric energy transmission system includes that coil radius is r and the transmitting coil being coaxially disposed, repeating coil and receiving coil, Distance between transmitting coil and receiving coil is d₀₂, and meet d₀₂=(10～12) r；Described transmitting coil and receiving coil The number of turn be N, the number of turn of described repeating coil is 2N, described repeating coil access compensate capacitance loop effective circle Number is adjustable in the range of 1～2N, distance d between described repeating coil and transmitting coil₀₁Adjustable；Described method include as Lower step:

1), for a certain dead load R_L, set the 0.1r unit displacement as repeating coil, change relaying successively The position of coil, dynamically changes described repeating coil on each position and accesses the effective turn of compensation capacitance loop and adjust Compensate electric capacity consistent to system resonance frequencies, if the bearing power emergent power peak point of described receiving coil, then should Power peak point is set to mesh power point and measures efficiency of transmission now；Distance d at repeating coil Yu transmitting coil₀₁ And distance d of repeating coil and receiving coil₁₂It is all higher than in the range of 2r, obtains being made up of several mesh power points Mesh power point set and the efficient point set being made up of the efficient point corresponding to mesh power point；

2), from mesh power point set and corresponding efficient point set, select meet load power demand and have the most efficient The point of rate is as the operating point of radio energy transmission system；

3) position and the described repeating coil access compensation capacitance loop of repeating coil, is adjusted according to the operating point selected Effective turn, it is achieved the optimization of system-power efficiency.

A kind of radio energy transmission system power efficiency optimization method the most according to claim 1, it is characterised in that: Described step 1) in, also include the calibration steps to described power peak point:

A), for arbitrary described power peak point, position and repeating coil according to corresponding repeating coil are accessed and are compensated The effective turn of capacitance loop, is calculated the mutual inductance M of repeating coil and transmitting coil₀₁, transmitting coil and receiving coil Mutual inductance M₀₂, the mutual inductance M of repeating coil and receiving coil₁₂；

B), according to described M₀₁、M₀₂、M₁₂It is calculated transmitting coil reflected umpedance R on repeating coil_ref0→1、 Repeating coil transmitting impedance R on receiving coil_ref1→2, transmitting coil reflected umpedance R on receiving coil_ref0→2With And the impedance loss coefficient Γ of repeating coil_0→1:

$R_{ref0\→1}=\frac{{\left({\mathrm{\ωM}}_{01}\right)}^2}{r_s+r_0}$

$R_{ref1\→2}=\frac{{\left({\mathrm{\ωM}}_{12}\right)}^2}{r_1}$

$R_{ref0\→2}=\frac{{\left({\mathrm{\ωM}}_{02}\right)}^2}{r_s+r_0}$

${\mathrm{\Γ}}_{0\→1}=\frac{r_1}{R_{ref0\→1}+r_1}$

Wherein, r_sFor connecting the internal resistance of the high frequency electric source of transmitting coil, r₀For the internal resistance of transmitting coil, r₁For repeating coil Internal resistance, r₂Internal resistance for receiving coil；ω is radio energy transmission system resonance angular frequency；

C), by described R_ref0→1、R_ref1→2、R_ref0→2And Γ_0→1Substitute in following formula, it is judged that whether formula is set up:

$R_L=\sqrt{4({\mathrm{\Γ}}_{0\→1}-{{\mathrm{\Γ}}_{0\→1}}^2)R_{ref0\→2}{R}_{ref1\→2}+{\[{\mathrm{\Γ}}_{0\→1}(R_{ref0\→2}+R_{ref1\→2})+r_2\]}^2}$

If this formula is false, then mesh power point corresponding for this power peak point and efficient point are deleted from set.

Beneficial effect: a kind of based on peak power coupling the radio energy transmission system power efficiency optimization side of the present invention Method, for requiring medium transmission range and emitting side and the most immutable radio energy transmission system of reception side parameter, logical Overregulate the distance between repeating coil and transmitting coil and the method changing the repeating coil number of turn, change itself and transmitting coil And to realize the same repeating coil that is supported on, there is the different number of turn and diverse location from the mutual inductance relationships between receiving coil Shi Duodian power match.This method achieve system access a certain fixed size load time produce multiple mesh power point with And the efficient point corresponding to mesh power point；Secondly according to loading demand, at produced multiple mesh power points and right The efficient point answered is chosen suitable power and the efficient point operating point as system, it is possible to meet the load need for power On the premise of asking, efficiency and power are optimized.

Accompanying drawing explanation

Fig. 1 is the radio energy transmission system structure chart with repeating coil；

Fig. 2 is the radio energy transmission system equivalent circuit diagram with repeating coil；

Fig. 3 is the scattergram of unequally loaded power match point；

Fig. 4 is optimal power and the efficient point of a certain dead load.

Detailed description of the invention

Below in conjunction with the accompanying drawings the present invention is done and further explain.

As it is shown in figure 1, in a kind of radio energy transmission system power efficiency optimization method based on peak power coupling, should Radio energy transmission system includes that coil radius is r and the transmitting coil being coaxially disposed, repeating coil and receiving coil, Distance between transmitting coil and receiving coil is d₀₂, and meet d₀₂=(10～12) r.Transmitting coil series connection primary compensates electricity Connecting high frequency electric source after appearance, the adjustable relaying of repeating coil series connection compensates electric capacity, after receiving coil series connection secondary compensation electric capacity For connecting load.The number of turn of transmitting coil and receiving coil is N, and the number of turn of repeating coil is 2N, repeating coil The effective turn accessing compensation capacitance loop is adjustable in the range of 1～2N, distance d between repeating coil and transmitting coil₀₁ Adjustable.It is illustrated in figure 2 the equivalent circuit diagram of this radio energy transmission system, U_sFor high frequency electric source, r_sFor the internal resistance of source, L₀, L₁, L₂It is respectively transmitting coil, repeating coil, the self-induction of receiving coil, M₀₁、M₁₂、M₀₂It is respectively and launches Mutual inductance between coil and repeating coil, repeating coil and receiving coil, transmitting coil and receiving coil, r₀、r₁And r₂ It is respectively transmitting coil, repeating coil and the internal resistance of receiving coil, C₀、C₁And C₂It is respectively radiating circuit, middle relay Road and the resonance compensation electric capacity of reception circuit.R_LThe load connect by receiving coil.The frequency of high frequency electric source and resonance mechanism Resonant frequency keep consistent, i.e. f=1/ (2 π sqrt (L₀ C₀))=1/ (2 π sqrt (L₁ C₁))=1/ (2 π sqrt (L₂ C₂))。

This method comprises the steps:

1), for a certain dead load R_L, set the 0.1r unit displacement as repeating coil, change relaying successively The position of coil, dynamically changes described repeating coil on each position and accesses the effective turn of compensation capacitance loop and adjust Compensate electric capacity consistent to system resonance frequencies, if the bearing power emergent power peak point of receiving coil, then by this power Peak point is set to mesh power point and measures efficiency of transmission now.Distance d at repeating coil Yu transmitting coil₀₁In and Continue coil distance d with receiving coil₁₂It is all higher than in the range of 2r, obtains the coupling being made up of several mesh power points Power points set and the efficient point set being made up of the efficient point corresponding to mesh power point.

Step 1) in also include the calibration steps to power peak point each in mesh power point set, particularly as follows:

A), for arbitrary power peak point, position and repeating coil according to corresponding repeating coil are accessed and are compensated electric capacity The effective turn of loop, is calculated the mutual inductance M of repeating coil and transmitting coil₀₁, transmitting coil mutual with receiving coil Sense M₀₂, the mutual inductance M of repeating coil and receiving coil₁₂。

B), according to M₀₁、M₀₂、M₁₂It is calculated transmitting coil reflected umpedance R on repeating coil_ref0→1In, Continue coil transmitting impedance R on receiving coil_ref1→2, transmitting coil reflected umpedance R on receiving coil_ref0→2And The impedance loss coefficient Γ of repeating coil_0→1:

$R_{ref0\→1}=\frac{{\left({\mathrm{\ωM}}_{01}\right)}^2}{r_s+r_0}$

$R_{ref1\→2}=\frac{{\left({\mathrm{\ωM}}_{12}\right)}^2}{r_1}$

$R_{ref0\→2}=\frac{{\left({\mathrm{\ωM}}_{02}\right)}^2}{r_s+r_0}$

${\mathrm{\Γ}}_{0\→1}=\frac{r_1}{R_{ref0\→1}+r_1}$

Wherein, r_sFor connecting the internal resistance of the high frequency electric source of transmitting coil, r₀For the internal resistance of transmitting coil, r₁For repeating coil Internal resistance, r₂Internal resistance for receiving coil；ω is radio energy transmission system resonance angular frequency.

C), by R_ref0→1、R_ref1→2、R_ref0→2And Γ_0→1Substitute in following formula, it is judged that whether formula is set up:

$R_L=\sqrt{4({\mathrm{\Γ}}_{0\→1}-{{\mathrm{\Γ}}_{0\→1}}^2)R_{ref0\→2}{R}_{ref1\→2}+{\[{\mathrm{\Γ}}_{0\→1}(R_{ref0\→2}+R_{ref1\→2})+r_2\]}^2}$

If this formula is false, then mesh power point corresponding for this power peak point and efficient point are deleted from set. It judges that principle is, bearing power P_outWith load R_LResistance is relevant, to radio energy transmission system bearing power P_out Seek first derivative and to make reciprocal value be zero to obtain above formula, power match when i.e. meeting above formula, could be realized.

2), from mesh power point set and corresponding efficient point set, select meet load power demand and have the most efficient The point of rate is as the operating point of radio energy transmission system.

3) position and the described repeating coil access compensation capacitance loop of repeating coil, is adjusted according to the operating point selected Effective turn, it is achieved the optimization of system-power efficiency.

For making present embodiment apparent, with R_LNominal value be respectively 5 Ω, 10 Ω and 15 Ω as a example by this reality is described Execute mode.

First the deviation arranging load value is limited to 10%, i.e. with nominal value R_LAs a example by=5 Ω, load value in the range of 4.5 Ω～5.5 Ω.According to above-mentioned embodiment, when the number of turn of repeating coil from 1 circle to the variable range of 36 circles, launch Coil and distance d of repeating coil₀₁When 0.36m～0.62m is variable, it is thus achieved that power match point as shown in Figure 3 Scattergram, corresponding to the load that nominal value is 5 Ω, has 23 points and meets；Corresponding to the load that nominal value is 10 Ω, Have 15 points to meet.Each point both corresponds to a system when mesh power and load this mesh power of acquisition Efficiency.Further, to load R_LNominal value be respectively 5 Ω and 10 Ω as a example by, 3 obtained with reference to the accompanying drawings Mesh power and corresponding efficiency draw bearing power and system effectiveness figure, such as accompanying drawing 4.Under conditions of mesh power, root According to maximum transmitted theorem, system effectiveness is certainly less than 50%；Now, according to curve, select first to meet bearing power and want Seek and have the operating point optimal working point as system of peak efficiency.

The above is only the preferred embodiment of the present invention, it is noted that for those skilled in the art For, under the premise without departing from the principles of the invention, it is also possible to make some improvements and modifications, these improvements and modifications are also Should be regarded as protection scope of the present invention.

Claims (2)

1. a radio energy transmission system power efficiency optimization method based on peak power coupling, it is characterised in that: institute State radio energy transmission system and include that coil radius is r and the transmitting coil being coaxially disposed, repeating coil and receives line Circle, the distance between transmitting coil and receiving coil is d₀₂, and meet d₀₂=(10～12) r；Described transmitting coil and reception The number of turn of coil is N, and the number of turn of described repeating coil is 2N, and described repeating coil accesses and compensates having of capacitance loop The effect number of turn is adjustable in the range of 1～2N, distance d between described repeating coil and transmitting coil₀₁Adjustable；Described method bag Include following steps:

1), for a certain dead load R_L, set the 0.1r unit displacement as repeating coil, change relaying successively The position of coil, dynamically changes described repeating coil on each position and accesses the effective turn of compensation capacitance loop and adjust Compensate electric capacity consistent to system resonance frequencies, if the bearing power emergent power peak point of described receiving coil, then should Power peak point is set to mesh power point and measures efficiency of transmission now；Distance d at repeating coil Yu transmitting coil₀₁ And distance d of repeating coil and receiving coil₁₂It is all higher than in the range of 2r, obtains being made up of several mesh power points Mesh power point set and the efficient point set being made up of the efficient point corresponding to mesh power point；

2), from mesh power point set and corresponding efficient point set, select meet load power demand and have the most efficient The point of rate is as the operating point of radio energy transmission system；

3) position and the described repeating coil access compensation capacitance loop of repeating coil, is adjusted according to the operating point selected Effective turn, it is achieved the optimization of system-power efficiency.

A kind of radio energy transmission system power efficiency optimization method the most according to claim 1, it is characterised in that: Described step 1) in, also include the calibration steps to described power peak point:

A), for arbitrary described power peak point, position and repeating coil according to corresponding repeating coil are accessed and are compensated The effective turn of capacitance loop, is calculated the mutual inductance M of repeating coil and transmitting coil₀₁, transmitting coil and receiving coil Mutual inductance M₀₂, the mutual inductance M of repeating coil and receiving coil₁₂；

B), according to described M₀₁、M₀₂、M₁₂It is calculated transmitting coil reflected umpedance R on repeating coil_ref0→1、 Repeating coil transmitting impedance R on receiving coil_ref1→2, transmitting coil reflected umpedance R on receiving coil_ref0→2With And the impedance loss coefficient Γ of repeating coil_0→1:

$R_{ref0\→1}=\frac{{\left({\mathrm{\ωM}}_{01}\right)}^2}{r_s+r_0}$

$R_{ref1\→2}=\frac{{\left({\mathrm{\ωM}}_{12}\right)}^2}{r_1}$

$R_{ref0\→2}=\frac{{\left({\mathrm{\ωM}}_{02}\right)}^2}{r_s+r_0}$

${\mathrm{\Γ}}_{0\→1}=\frac{r_1}{R_{ref0\→1}+r_1}$

Wherein, r_sFor connecting the internal resistance of the high frequency electric source of transmitting coil, r₀For the internal resistance of transmitting coil, r₁For repeating coil Internal resistance, r₂Internal resistance for receiving coil；ω is radio energy transmission system resonance angular frequency；

C), by described R_ref0→1、R_ref1→2、R_ref0→2And Γ_0→1Substitute in following formula, it is judged that whether formula is set up:

$R_L=\sqrt{4({\mathrm{\Γ}}_{0\→1}-{{\mathrm{\Γ}}_{0\→1}}^2)R_{ref0\→2}{R}_{ref1\→2}+{\[{\mathrm{\Γ}}_{0\→1}(R_{ref0\→2}+R_{ref1\→2})+r_2\]}^2}$

If this formula is false, then mesh power point corresponding for this power peak point and efficient point are deleted from set.