CN104794349A - Corrosion prevention state estimation and control method for ship and ocean structure - Google Patents

Abstract

The invention discloses a corrosion prevention state estimation and control method for a ship and an ocean structure. The corrosion prevention state estimation and control method includes the step of building a database, wherein a ship and ocean structure boundary element model is built, protective potential data in different time periods in the full-service-life period of each node of a triangular unit are obtained, and the corrosion state estimation database is built; the step of calculation and estimation, wherein the space coordinates of a reference electrode monitoring point are obtained, the space coordinates of three nodes of a triangular grid where the electrode monitoring point is located and protective potential data in each time period are taken from the database, and the current corrosion state of the outer surface of the ship and the ocean structure is judged; the step of outputting and controlling a protective power source, wherein a direct current power source is controlled to output a corresponding potential value by comparing the measured protective potential value of a control point reference electrode and the protective potential reference value.

Description

Boats and ships and marine structure corrosion protection state estimation and control method

Technical field

The present invention relates to the assessment of a kind of etch state and control method, particularly relate to assessment and the control method of a kind of boats and ships based on boundary element principle and marine structure corrosion protection state.Relate generally to Patent classificating number G01 to measure; Test G01N is by means of measuring the chemistry of material or physical property is tested or the weatherability of analysis of material G01N17/00 test material, corrosion-resistant, or resistance to light.

Background technology

Boats and ships and marine structure adopt the corrosion protection system of corrosion resistant coating and cathodic protection compound usually; in protection period, the guard mode on its surface can be characterized by some parameters, mainly comprises protection potential; protecting current density, the measurement of anode current and anode voltage.

The size of protection potential is directly connected to the quality of the protected effect of steel construction, and As time goes on, protection potential can change.Current potential only just can make boats and ships and marine structure be subject to effective protection within certain numerical value scope, and current potential is just crossing (under proteciton) and current potential excessively negative (overprotection) all should be avoided.Therefore corrosion protection state estimation is carried out according to the protection potential distribution situation of boats and ships and marine structure submerged structure outside surface; simultaneously according to assessment result in real time anticathode protection system output current carry out adjusting thus control its corrosion protection state, to ensureing being significant of boats and ships and marine structure safe operation and prevention failure accidents.

The patent No. is that " trenchless construction large-diameter pipeline corrosion controlling and monitoring system " by name of CN101762622A discloses a kind of trenchless construction large-diameter pipeline corrosion controlling and monitoring system, but this system only carries out relevant monitoring for trenchless construction large diameter pipeline corrosion data, prior art only gives the Forecasting Methodology of the pipeline residual life based on corrosion rate electrochemical model in medium, do not set up etch state database, not by Data Comparison in Monitoring Data and database and then evaluation of corrosion state yet.The patent No. is that " shaft corrosion evaluating device " of CN202267645U discloses a kind of shaft corrosion evaluating device, this device uses weight-loss method evaluation of corrosion speed and estimates residual life, the possibility producing personal error in operating process is comparatively large, and credible result degree is low.

Summary of the invention

The present invention is directed to the proposition of above problem, and a kind of boats and ships of development and marine structure corrosion protection state estimation and control method, there are following steps:

Database step: set up boats and ships and marine structure submerged structure boundary element model, obtains the triangular element numbering of boats and ships and marine structure submerged structure, the node serial number of composition triangular element and node coordinate by pre-treatment; By numerical simulation calculation, show that each node of described triangular element is in life cycle management, protection potential data in different time sections also set up etch state assessment data storehouse;

Calculate appraisal procedure: the volume coordinate obtaining contrast electrode monitoring point, the volume coordinate of triangular mesh three nodes at place, electrode monitoring point described in called data storehouse and the protection potential data in each time period, the linear interpolation method under usable floor area coordinate calculates the protection potential reference value in each time period of described monitoring point; Relatively the protection potential measured value and described protection potential reference value that obtain are surveyed in monitoring point, determine immediate potential reference value, inquire about described database and find etch state file corresponding to described immediate potential reference value to judge the etch state of current boats and ships and marine structure submerged structure outside surface;

Direct supply exports rate-determining steps: use numerical simulation to calculate the range of influence of each direct supply respectively; Choose the reference mark in each range of influence; Set the protection potential reference value at each reference mark, the direct supply of the protection potential value comparing the actual measurement of reference mark contrast electrode to described protection potential reference value thus described in controlling exports corresponding potential value.

Described linear difference method is specific as follows:

Volume coordinate (the x of known described monitoring point e _e, y _e, z _e) and the coordinate on place triangular element three summits and protection potential; Described monitoring point e is arranged in the triangle of three node a, b, c formations or is positioned on triangle border or summit;

Utilize area coordinate, the position of e point can by two numbers decisions below

$\begin{array}{cc}{l}_i=\frac{{\mathrm{\Δ}}_i}{{\mathrm{\Δ}}_{\mathrm{abc}}}& l_j=\frac{{\mathrm{\Δ}}_j}{{\mathrm{\Δ}}_{\mathrm{abc}}}\end{array}$

Wherein Δ is the area of triangle abc, Δ _i, Δ _jthe area of triangle abe and triangle ace respectively, e (l _i, l _j) be called area coordinate;

As cut-off angle coordinate system Oxy, x can be used _eand y _erepresent each leg-of-mutton area, so Δ _iarea be ${\mathrm{\Δ}}_i=\frac{1}{2}(a_i+b_i{x}_e+c_i{y}_e),$ In formula

$\left\{\begin{array}{c}{a}_i=x_a{y}_b-x_b{y}_a\\ b_i=y_c-y_b\\ c_i=x_b-x_a\end{array}\right.$

Due in uniform electric field, certain any potential value is only relevant with this position coordinates, therefore e point current potential under area coordinate system

Φ _e＝f(x _e,y _e)＝f(l _i,l _j)

In addition, electric field with apart from linear, therefore establish

Φ _e＝mx _e+ny _e+c＝Ml _i+Nl _j+C

A, b, c 3 area coordinates and potential value are substituted into above formula, following equation can be obtained,

$\left\{\begin{array}{c}{\mathrm{\Φ}}_a=C\\ {\mathrm{\Φ}}_b=N+C\\ {\mathrm{\Φ}}_c=M+C\end{array}\right.$

Solve above-mentioned equation can obtain, M=Φ _c-Φ _a, N=Φ _b-Φ _a, C=Φ _a.

Therefore the protection potential reference value of monitoring point e can be obtained

Φ _e＝(Φ _c-Φ _a)l _i+(Φ _b-Φ _a)l _j+Φ _a。

Compare monitoring point in described calculating appraisal procedure and survey the protection potential measured value and described protection potential reference value that obtain, judge that the method for the etch state of current monitoring point is as follows:

Extract the protection potential reference value of each monitoring point, form the etch state matrix of M*N:

${\left[\begin{array}{ccccccc}{v}_{11}& v_{12}& ...& v_{1i}& v_{1(i+1)}& ...& v_{1N}\\ v_{21}& v_{22}& ...& v_{2i}& v_{2(i+1)}& ...& v_{2N}\\ ...& ...& & & ...& & ...\\ v_{M1}& v_{M2}& ...& v_{\mathrm{Mi}}& v_{M(i+1)}& ...& v_{\mathrm{MN}}\end{array}\right]}_{M\×N}$

Wherein M is the number of etch state file, and N is the quantity of boats and ships and marine structure submerged structure outside surface monitoring point;

The protection potential measured value of monitoring point contrast electrode is formed a N dimensional vector, and wherein N is submerged structure outside surface monitoring point quantity;

Ask the mould of each row vector difference in the etch state matrix of monitoring N dimensional vector and the M*N obtained, namely the etch state file at wherein minimum with the mould of monitoring the N dimensional vector difference obtained row vector place represents current etch state, can be obtained the etch state of boats and ships and marine structure submerged structure outside surface by this etch state file.

Also there is data screening step:

T potential vectors is: V _1t, V _2t..., V _it..., V _nt;

T+1 moment potential vectors is: V _{1 (t+1)}, V _{2 (t+1)}..., V _{i (t+1)}..., V _{n (t+1)};

If V _{i (t+1)}-V _it> ε, then delete data V in N dimensional vector _{i (t+1)}, think to lose efficacy in i-th monitoring point; Delete the data of the i-th row in etch state matrix simultaneously.

The described method choosing range of influence is specially: utilize numerical simulation to calculate the submerged structure outside surface Potential distribution situation under the independent electric power thus supplied of each direct supply respectively, find the separatrix in DC power supply region, determine the range of influence of each direct supply.

The described method choosing reference mark is specially: set multiple DC power output voltage, utilize numerical simulation calculation, obtains the current potential of the current potential highs and lows under different DC power output voltage.And be horizontal ordinate with DC power output voltage, respectively with the current potential of current potential highs and lows for ordinate curve plotting.Article two, in curve, the point (peak or minimum point) of the representative that slope is larger is the reference mark in each region.

Also there is alarming step: if V _{i (t+1)}-V _it> ε, then delete data V in N dimensional vector _{i (t+1)}, think to lose efficacy in i-th monitoring point, send warning.

Owing to have employed technique scheme; boats and ships provided by the invention and marine structure etch state appraisal procedure; by the method for finite element analysis, linear interpolation analysis and numerical simulation; accurately according to the protection potential numerical value of current monitoring point, the etch state of current boats and ships and marine structure underwater portion can be estimated.Compared to existing analytical approach, its current potential can be effectively avoided just to cross or excessively negative.As time goes on, the total current required for impressed current cathodic protection system can increase gradually, can automatically adjust direct supply output current in real time, ensure that surface potential is in zone of reasonableness, instead of traditional manual shift by said method.Simultaneously also can according to result of calculation to contrast electrode Failure Alarm, can prevent from losing efficacy the inaccurate of the measurement result caused due to contrast electrode.

Accompanying drawing explanation

In order to the technical scheme of clearer explanation embodiments of the invention or prior art, introduce doing one to the accompanying drawing used required in embodiment or description of the prior art simply below, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.

Fig. 1 is area coordinate interpolation method schematic diagram of the present invention

Fig. 2 is the schematic diagram of etch state database of the present invention

Fig. 3 is process flow diagram of the present invention

Embodiment

For making the object of embodiments of the invention, technical scheme and advantage clearly, below in conjunction with the accompanying drawing in the embodiment of the present invention, clear complete description is carried out to the technical scheme in the embodiment of the present invention:

As Figure 1-3: a kind of boats and ships and marine structure corrosion protection state estimation and control method, mainly comprise the steps:

Database step: set up boats and ships and marine structure submerged structure boundary element model, obtains the triangular element numbering of boats and ships and marine structure submerged structure, the node serial number of composition triangular element and node coordinate by numerical simulation calculation; By numerical simulation calculation, show that each node of described triangular element is in life cycle management, protection potential data in different time sections also set up etch state database, as shown in Figure 2.

Calculate appraisal procedure: the volume coordinate obtaining contrast electrode monitoring point, the volume coordinate of triangular mesh three nodes at this place, monitoring point and the protection potential data in each time period in called data storehouse, the linear interpolation method under usable floor area coordinate calculates the protection potential reference value in the time period of described monitoring point; Relatively the protection potential measured value and described protection potential reference value that obtain are surveyed in monitoring point, determine immediate potential reference value, inquire about described database and find etch state file corresponding to described immediate potential reference value to judge the etch state of current boats and ships and marine structure submerged structure outside surface;

Direct supply exports rate-determining steps: use numerical simulation to calculate the range of influence of each direct supply respectively; Choose the reference mark in each range of influence; Set the protection potential reference value at each reference mark, the direct supply of the protection potential value comparing the actual measurement of reference mark contrast electrode to described protection potential reference value thus described in controlling exports corresponding potential value.

In above-mentioned steps, the computational mathematics model that numerical simulation adopts is as follows

The mathematical model of boats and ships and Cathodic Protection System for Marine Structure problem can be summed up as the math equation (in territory governing equation) describing seawater electrolysis matter region (Ω) inner potential state and current phasor state, the math equation (boundary condition) describing potential state and current status on all boundary.

Governing equation

In seawater electrolysis matter region, the current potential in the electric field that hull cathodic protection system produces and current density meet equation:

$q=-\frac{1}{\mathrm{\ρ}}\▿\mathrm{\Φ}---\left(1\right)$

In formula: q represents current density, Φ is current potential, and ρ is extra large resistivity of water.

When the electric field that cathodic protection system produces reaches equilibrium state, can obtain governing equation in territory is:

$\frac{1}{\mathrm{\ρ}}{\▿}^2\mathrm{\Φ}=0---\left(2\right)$

Boundary condition

The intact position S of boats and ships wet structure corrosion-inhibiting coating ₁with Sea surface boundary S _wthe current density that should meet perpendicular to boundary direction is " 0 "; Coating damage position S ₂potential state and current status between relation meet polarization curve: the enough S at a distance of distance hull _∞current potential be constant, current density is " 0 ".In sum, the boundary condition of hull cathodic protection problem is as equation (3).

$\left\{\begin{array}{cc}q=\frac{1}{\mathrm{\ρ}}\frac{\∂\mathrm{\Φ}}{\∂n}=0& \mathrm{on}{\mathrm{}S}_1\\ q=\frac{1}{\mathrm{\ρ}}\frac{\∂\mathrm{\Φ}}{\∂n}=f_{\∞}\left(\mathrm{\Φ}\right)& \mathrm{on}\mathrm{}{S}_2\\ q=\frac{1}{\mathrm{\ρ}}\frac{\∂\mathrm{\Φ}}{\∂n}=0& \mathrm{on}{\mathrm{}S}_w\\ \mathrm{\Φ}={\mathrm{\Φ}}_{\∞}& \mathrm{on}\mathrm{}{S}_{\∞}\\ q=\frac{1}{\mathrm{\ρ}}\frac{\∂\mathrm{\Φ}}{\∂n}=0& \mathrm{on}{\mathrm{}S}_{\∞}\end{array}\right.---\left(3\right)$

Boundary integral equation

From the weighted residual equation that (3) formula is corresponding, introduce elementary solution and set up boundary integral equation:

$\frac{1}{\mathrm{\ρ}}{C}_i{\mathrm{\Φ}}_i+{\∫}_s{q}^{*}(P,Q)\mathrm{\ΦdS}={\∫}_s{\mathrm{q\Φ}}^{*}(P,Q)\mathrm{dS}+\frac{1}{\mathrm{\ρ}}{\mathrm{\Φ}}_{\∞}---\left(4\right)$

In formula, Ci is shape coefficient, only depends on the boundary geometry in physical model.

Equation (4) is carried out on border discretely obtain the boundary integral equation of shape as (5).

HΦ＝Gq (5)

In formula, H and G is matrix of coefficients.

(3) formula substituted into, row iteration of going forward side by side solves the potential value and normal direction current density that can obtain each node on border.

Described linear difference method is specific as follows:

Volume coordinate (the x of known described monitoring point e _e, y _e, z _e) and the coordinate on place triangular element three summits and protection potential; Described monitoring point e is arranged in the triangle of three node a, b, c formations or is positioned on triangle border or summit;

Utilize area coordinate, the position of e point can by two numbers decisions below

$\begin{array}{cc}{l}_i=\frac{{\mathrm{\Δ}}_i}{{\mathrm{\Δ}}_{\mathrm{abc}}}& l_j=\frac{{\mathrm{\Δ}}_j}{{\mathrm{\Δ}}_{\mathrm{abc}}}\end{array}$

Wherein Δ is the area of triangle abc, Δ _i, Δ _jthe area of triangle abe and triangle ace respectively; E (l _i, l _j) be called area coordinate.

As cut-off angle coordinate system O _xy, can x be used _eand y _erepresent each leg-of-mutton area, so Δ _iarea be ${\mathrm{\Δ}}_i=\frac{1}{2}(a_i+b_i{x}_e+c_i{y}_e),$ In formula

$\left\{\begin{array}{c}{a}_i=x_a{y}_b-x_b{y}_a\\ b_i=y_c-y_b\\ c_i=x_b-x_a\end{array}\right.$

Due in uniform electric field, certain any potential value is only relevant with this position coordinates, therefore e point current potential under area coordinate system;

Φ _e＝f(x _e,y _e)＝f(l _i,l _j)

In addition, electric field with apart from linear, therefore establish

Φ _e＝mx _e+ny _e+c＝Ml _i+Nl _j+C

A, b, c 3 area coordinates and potential value are substituted into above formula, following equation can be obtained,

$\left\{\begin{array}{c}{\mathrm{\Φ}}_a=C\\ {\mathrm{\Φ}}_b=N+C\\ {\mathrm{\Φ}}_c=M+C\end{array}\right.$

Solve above-mentioned equation can obtain, M=Φ _c-Φ _a, N=Φ _b-Φ _a, C=Φ _a.

Therefore the protection potential reference value of monitoring point e can be obtained

Φ _e＝(Φ _c-Φ _a)l _i+(Φ _b-Φ _a)l _j+Φ _a。

Compare monitoring point in described calculating appraisal procedure and survey the protection potential measured value and described protection potential reference value that obtain, judge that the method for the etch state of current monitoring point is as follows:

Extract the protection potential reference value of each monitoring point, form the etch state matrix of M*N:

${\left[\begin{array}{ccccccc}{v}_{11}& v_{12}& ...& v_{1i}& v_{1(i+1)}& ...& v_{1N}\\ v_{21}& v_{22}& ...& v_{2i}& v_{2(i+1)}& ...& v_{2N}\\ ...& ...& & & ...& & ...\\ v_{M1}& v_{M2}& ...& v_{\mathrm{Mi}}& v_{M(i+1)}& ...& v_{\mathrm{MN}}\end{array}\right]}_{M\×N}$

Wherein M is the number of etch state file, and N is the quantity of boats and ships and marine structure submerged structure outside surface monitoring point;

The protection potential measured value of monitoring point contrast electrode is formed a N dimensional vector, and wherein N is submerged structure outside surface monitoring point quantity;

Ask the mould of each row vector difference in the etch state matrix of monitoring N dimensional vector and the M*N obtained, namely the etch state file that wherein minimum with the mould of monitoring the N dimensional vector difference obtained row vector is sitting in represents current etch state, can be obtained the etch state of boats and ships and marine structure submerged structure outside surface by this etch state file.

Also there is data screening step:

T potential vectors is: V1t, V2t ..., Vit ..., VNt;

T+1 moment potential vectors is: V1 (t+1), V2 (t+1) ..., Vi (t+1) ..., VN (t+1);

If Vi (t+1)-Vit> is ε, then in N dimensional vector, delete data Vi (t+1), think to lose efficacy in i-th monitoring point; Delete the data of the i-th row in etch state matrix simultaneously.

The method of described selected characteristic point range of influence is specially: utilize numerical simulation to calculate the submerged structure outside surface Potential distribution situation under the independent electric power thus supplied of each direct supply respectively, find the separatrix in each DC power supply region, determine the range of influence of each direct supply.

The method choosing reference mark is specially: set multiple DC power output voltage, utilize numerical simulation calculation, obtains the current potential of the current potential highs and lows under different DC power output voltage.And with the output voltage of direct supply for horizontal ordinate, respectively with the current potential of current potential highs and lows for ordinate curve plotting.Article two, in curve, the point (peak or minimum point) of the representative that slope is larger is the reference mark in each region.

Further, the present invention also has alarming step: if Vi (t+1)-Vit> is ε, then in N dimensional vector, delete data Vi (t+1), thinks to lose efficacy in i-th monitoring point, sends warning.

Direct supply exports rate-determining steps and is specially: determine position, reference mark, obtain its potential value; If reference mark, on the node of described triangular mesh unit, directly draws the output potential at reference mark according to described etch state file; If reference mark is at triangle interior, then the linear interpolation method under described area coordinate is utilized to calculate the output potential at reference mark by the coordinate figure of adjacent node and potential value.

When reality uses, direct supply extracts the potential calculation value at reference mark, each direct supply range of influence according to the etch state file obtained in etch state evaluation process, direct supply adjusts its magnitude of voltage exported automatically, until the potential measurement value at each reference mark is equal with potential calculation value.

The above; be only the present invention's preferably embodiment; but protection scope of the present invention is not limited thereto; anyly be familiar with those skilled in the art in the technical scope that the present invention discloses; be equal to according to technical scheme of the present invention and inventive concept thereof and replace or change, all should be encompassed within protection scope of the present invention.

Claims (7)

1. boats and ships and marine structure corrosion protection state estimation and a control method, has following steps:

Database step: the boundary element model setting up boats and ships and marine structure submerged structure, obtains the triangular element numbering of boats and ships and marine structure submerged structure, the node serial number of composition triangular element and node coordinate by pre-treatment; By numerical simulation calculation, show that each node of described triangular element is in life cycle management, protection potential data in different time sections also set up etch state assessment data storehouse;

Calculate appraisal procedure: the volume coordinate obtaining contrast electrode monitoring point, the volume coordinate of triangular mesh three nodes at place, electrode monitoring point described in called data storehouse and the protection potential data in each time period, the linear interpolation method under usable floor area coordinate calculates the protection potential reference value in each time period of described monitoring point; Relatively the protection potential measured value and described protection potential reference value that obtain are surveyed in monitoring point, determine immediate potential reference value, inquire about described database and find etch state file corresponding to described immediate potential reference value to judge the etch state of current boats and ships and marine structure submerged structure outside surface;

Direct supply exports rate-determining steps: use numerical simulation to calculate the range of influence of each direct supply respectively; Choose the reference mark in each range of influence; Set the protection potential reference value at each reference mark, the direct supply of the protection potential value comparing the actual measurement of reference mark contrast electrode to described protection potential reference value thus described in controlling exports corresponding potential value.

2. boats and ships according to claim 1 and marine structure corrosion protection state estimation and control method, is further characterized in that: described linear difference method is specific as follows:

Volume coordinate (the x of known described monitoring point e _e, y _e, z _e) and the coordinate on place triangular element three summits and protection potential; Described monitoring point e is arranged in the triangle of three node a, b, c formations or is positioned on triangle border or summit;

Utilize area coordinate, the position of e point can by two numbers decisions below

$\begin{array}{cc}{l}_i=\frac{{\mathrm{\Δ}}_i}{{\mathrm{\Δ}}_{\mathrm{abc}}}& l_j=\frac{{\mathrm{\Δ}}_j}{{\mathrm{\Δ}}_{\mathrm{abc}}}\end{array}$

Wherein Δ is the area of triangle abc, Δ _i, Δ _jthe area of triangle abe and triangle ace respectively, e (l _i, l _j) be called area coordinate;

As cut-off angle coordinate system Oxy, x can be used _eand y _erepresent each leg-of-mutton area, so Δ _iarea be ${\mathrm{\Δ}}_i=\frac{1}{2}(a_i+b_i{x}_e+c_i{y}_e),$ In formula

$\left\{\begin{array}{c}{a}_i=x_a{y}_b-x_b{y}_a\\ b_i=y_c-y_b\\ c_i=x_b-x_a\end{array}\right.$

Due in uniform electric field, certain any potential value is only relevant with this position coordinates, therefore e point current potential under area coordinate system,

Φ _e＝f(x _e,y _e)＝f(l _i,l _j)

In addition, electric field with apart from linear, therefore establish

Φ _e＝mx _e+ny _e+c＝Ml _i+Nl _j+C

A, b, c 3 area coordinates and potential value are substituted into above formula, following equation can be obtained,

$\left\{\begin{array}{c}{\mathrm{\Φ}}_a=C\\ {\mathrm{\Φ}}_b=N+C\\ {\mathrm{\Φ}}_c=M+C\end{array}\right.$

Solve above-mentioned equation can obtain, M=Φ _c-Φ _a, N=Φ _b-Φ _a, C=Φ _a.

Therefore the protection potential reference value of monitoring point e can be obtained

Φ _e＝(Φ _c-Φ _a)l _i+(Φ _b-Φ _a)l _j+Φ _a。

3. boats and ships according to claim 2 and marine structure corrosion protection state estimation and control method; be further characterized in that: compare monitoring point in described calculating appraisal procedure and survey the protection potential measured value and described protection potential reference value that obtain, judge that the method for the etch state of current monitoring point is as follows:

Extract the protection potential reference value of each monitoring point, form the etch state matrix of M*N:

${\left[\begin{array}{ccccccc}{v}_{11}& v_{12}& ...& v_{1i}& v_{1(i+1)}& ...& v_{1N}\\ v_{21}& v_{22}& ...& v_{2i}& v_{2(i+1)}& ...& v_{2N}\\ ...& ...& & & ...& & ...\\ v_{M1}& v_{M2}& ...& v_{\mathrm{Mi}}& v_{M(i+1)}& ...& v_{\mathrm{MN}}\end{array}\right]}_{M\×N}$

Wherein M is the number of etch state file, and N is the quantity of boats and ships and marine structure submerged structure outside surface monitoring point;

The protection potential measured value of monitoring point contrast electrode is formed a N dimensional vector, and wherein N is submerged structure outside surface monitoring point quantity;

Ask the mould of each row vector difference in the etch state matrix of monitoring N dimensional vector and the M*N obtained, namely the etch state file at wherein minimum with the mould of monitoring the N dimensional vector difference obtained row vector place represents current etch state, can be obtained the etch state of boats and ships and marine structure submerged structure outside surface by this etch state file.

4. boats and ships according to claim 3 and marine structure corrosion protection state estimation and control method, is further characterized in that: also have data screening step:

T potential vectors is: V _1t, V _2t..., V _it..., V _nt;

T+1 moment potential vectors is: V _{1 (t+1)}, V _{2 (t+1)}..., V _{i (t+1)}..., V _{n (t+1)};

If V _{i (t+1)}-V _it> ε, then delete data V in N dimensional vector _{i (t+1)}, think to lose efficacy in i-th monitoring point; Delete the data of the i-th row in etch state matrix simultaneously.

5. boats and ships according to claim 1 and marine structure corrosion protection state estimation and control method, be further characterized in that: described in choose range of influence method be specially: utilize numerical simulation to calculate the submerged structure outside surface Potential distribution situation under the independent electric power thus supplied of each direct supply respectively, find the separatrix in DC power supply region, determine the range of influence of each direct supply.

6. boats and ships according to claim 5 and marine structure corrosion protection state estimation and control method, be further characterized in that: described in choose reference mark method be specially: set multiple DC power output voltage, utilize numerical simulation calculation, obtain the current potential of the current potential highs and lows under different DC power output voltage.And be horizontal ordinate with DC power output voltage, respectively with the current potential of current potential highs and lows for ordinate curve plotting.Article two, in curve, the point (peak or minimum point) of the representative that slope is larger is the reference mark in each region.

7. boats and ships according to claim 4 and marine structure corrosion protection state estimation and control method, be further characterized in that: also have alarming step: if V _{i (t+1)}-V _it> ε, then delete data V in N dimensional vector _{i (t+1)}, think to lose efficacy in i-th monitoring point, send warning.