A disconnector system based on dynamic control of contact heads

Abstract

The present invention discloses a disconnector system based on dynamic contact control, comprising: an arc detection unit, which includes a current sensor, a voltage sensor, and an optical sensor; a contact motion control unit, which includes a plurality of servo motors and a motion controller, the servo motors drive the contacts to run according to a designed trajectory, and the motion controller is used to execute a trajectory planning algorithm; a protection unit, which includes an overcurrent protection element and a temperature detection element; a performance evaluation unit, which includes a data recording module and a life prediction module. The present invention has the following beneficial effects: This disconnector system based on dynamic contact control can optimize the motion trajectory and speed of the contacts, not only solve the problem of limited space, but also reduce the equipment cost and improve the reliability and maintainability of the system.

Description

Technical Field

[0001] The present invention relates to a disconnector control system, and particularly to a disconnector system based on dynamic contact control. Background Art

[0002] As an important switching device in the power system, the disconnector is mainly used to achieve electrical isolation when the circuit is disconnected or closed. In an ideal state, the disconnector should be operated for opening and closing under no-load conditions. However, in actual operation, due to operation errors or special working conditions, sometimes the disconnector is operated for opening and closing under a current-carrying state, and in this case, an arc phenomenon will occur.

[0003] When the contacts of the disconnector are separated, due to the sudden interruption of the current, a high-temperature arc will be generated in the contact gap. This arc will not only damage the contact surface, causing ablation and deformation of the contact material, but also may trigger more serious safety accidents. Especially in a high-voltage power system, the energy of the arc is greater and the destructiveness is stronger. In addition, when a system failure or misoperation causes load-breaking, the arc phenomenon will be more intense, bringing serious safety hazards to the equipment and operators.

[0004] In the prior art, the solution to the arc problem mainly relies on arc extinguishing devices. Traditional arc extinguishing devices usually adopt structures such as arc extinguishing chambers and arc extinguishing grid plates, and achieve arc extinguishing by extending the arc path, dividing the arc, and forced cooling. However, this solution has obvious technical limitations in the application of disconnectors. The first is the space limitation problem. The installation position of the disconnector is usually relatively compact, and the space reserved for the arc extinguishing device is very limited, making it difficult to install traditional arc extinguishing structures. Secondly, the original design intention of the disconnector is not to be used as an arc extinguishing component such as a circuit breaker. Adding an arc extinguishing device will not only increase the equipment cost, but also increase the structural complexity and affect the reliability of the equipment.

[0005] At the same time, the use of traditional arc extinguishing devices also brings the problem of increased maintenance costs. The components in the arc extinguishing device will wear and age after long-term use, and need to be regularly inspected and replaced, which increases the maintenance difficulty and operation cost of the equipment. In addition, in some special application scenarios, such as outdoor high-altitude areas, the performance of the arc extinguishing device will be affected by environmental factors, and the reliability is difficult to guarantee.

[0006] Therefore, it is of great significance to develop a disconnector system that does not require an additional arc extinguishing device, but realizes the arc extinguishing function by precisely controlling the movement of the contacts. Summary of the Invention

[0007] The object of the present invention is to provide a disconnector system based on dynamic contact control. This disconnector system based on dynamic contact control can optimize the movement trajectory and speed of the contacts, not only solve the problem of limited space, but also reduce the equipment cost, and improve the reliability and maintainability of the system.

[0008] The above technical object of the present invention is achieved through the following technical solutions:

[0009] A disconnector system based on dynamic contact control, comprising: an arc detection unit, the arc detection unit includes a current sensor, a voltage sensor and an optical sensor, the current sensor is used to collect arc current, the voltage sensor is used to collect arc voltage, and the optical sensor is used to detect the arc length and the spatial distribution state of the arc; a contact movement control unit, the contact movement control unit includes a plurality of servo motors and a motion controller, the servo motors drive the contacts to run according to the designed trajectory, and the motion controller is used to execute the trajectory planning algorithm; a protection unit, the protection unit includes an overcurrent protection element and a temperature detection element; a performance evaluation unit, the performance evaluation unit includes a data recording module and a life prediction module.

[0010] The present invention is further arranged as follows: the arc characteristics detected by the arc detection unit are described by the following arc characteristic equation:

[0011] ;

[0012] where, u arc (t) represents the arc voltage, l(t) is the arc length, i(t) is the arc current, the value range of the exponent n is 0.5≤n≤1.0, and the coefficients A, B, C, D are arc characteristic parameters.

[0013] The present invention is further arranged as follows: the spatial trajectory planning algorithm of the contacts is realized by the following formula:

[0014] ;

[0015] ;

[0016] ;

[0017] where, x0, y0, z0 are the initial position coordinates of the contacts, R is the radius of the movement trajectory on the horizontal plane, ω is the angular velocity, α, β are attenuation coefficients, and k is the movement rate in the vertical direction.

[0018] The present invention is further arranged as follows: the trajectory planning algorithm further includes a trajectory correction formula:

[0019] ;

[0020] ;

[0021] ;

[0022] ;

[0023] Among them, S0 is the initial correction amplitude, λ is the correction attenuation coefficient, T is the correction period, and [n x , n y , n z is the correction direction unit vector.

[0024] The present invention is further configured such that the movement speed state of the contact is controlled by the following formula:

[0025] ;

[0026] ;

[0027] .

[0028] Among them, V0 is the initial velocity, a is the acceleration. V max is the maximum velocity, t1 is the time required to accelerate to V max , t2 is the duration of uniform motion, and t3 is the time required to decelerate to 0.

[0029] The present invention is further configured such that the contact movement speed is controlled by the following dynamic speed optimization formula:

[0030] ;

[0031] Among them, V opt (t) is the optimized real-time speed of the contact, V(t) is the basic contact speed, k V is the speed correction coefficient, K κ is the curvature correction coefficient;

[0032] The speed correction coefficient k V is calculated by the formula:

[0033] ;

[0034] Among them, P max is the maximum arc power allowed by the system, Parc(t) is the real-time arc power, d(t) is the current distance between the contacts, d crit is the critical safety distance, and α, β are experimentally calibrated coefficients;

[0035] The curvature correction coefficient K κ is calculated by the formula:

[0036] ;

[0037] Among them, κ(t) is the real-time curvature of the contact trajectory, κ max is the maximum allowable curvature, and γ is the curvature decay exponent.

[0038] The present invention is further configured such that the overcurrent and overheat protection conditions of the protection unit are:

[0039] ;

[0040] Among them, k i is the adjustment coefficient, I rated is the rated current, T max is the threshold temperature, set to 150 °C.

[0041] The present invention is further configured such that the dynamic characteristics of the contact are described by the following equation:

[0042] ;

[0043] Among them, M is the mass, C is the damping coefficient, K is the stiffness coefficient, r is the displacement, F is the driving force, F s is the trajectory correction force.

[0044] The present invention is further configured such that the arc extinction time t ext recorded by the performance evaluation unit is calculated by the following formula:

[0045] ;

[0046] Among them, t f is the end time of the arc extinction process, t0 is the start time of the arc extinction process, and the set target is t ext ≤ 20 ms;

[0047] The energy loss situation is calculated according to the state during arc extinction, and the formula is as follows:

[0048] ;

[0049] Among them, E loss : total energy loss, the total energy consumption caused by the arc and current during the arc extinction process. P arc (t): arc power, determined by the arc voltage and current; : arc energy consumption, the total energy within the action time of the arc. : current loss, the heat loss caused by the contact resistance R(t). i(t): contact current; R(t): the change of the contact resistance over time.

[0050] The present invention is further configured such that the prediction of the contact life of the performance evaluation unit is calculated by the following formula:

[0051] ;

[0052] where L is the remaining contact life, L0 is the initial rated contact life, k is the reduction factor, and ∑W arc is the cumulative value of the arc energy, and W rated is the rated energy withstand value of the contact.

[0053] In summary, the present invention has the following beneficial effects:

[0054] This disconnector system based on contact dynamic control realizes an efficient arc extinguishing process without a traditional mechanical arc extinguishing device through accurate arc characteristic modeling and contact movement control. The system uses an arc characteristic equation to describe the dynamic behavior of the arc, and combines current, voltage, and optical sensors to monitor the arc state in real time. The contact movement path is designed through equations such as three-dimensional space trajectory planning, and a trajectory correction function is introduced to achieve dynamic adjustment to adapt to the changing characteristics of the arc.

[0055] Speed optimization adopts a segmented control strategy, and accurately adjusts the contact movement speed through a speed correction coefficient and a curvature correction coefficient. The system integrates an overcurrent and overheat protection mechanism, which triggers an emergency stop when the current or temperature exceeds the threshold, and the contact dynamic characteristic equation ensures the smoothness of the movement. Performance evaluation is quantitatively evaluated through indicators such as arc extinguishing time, energy loss, and contact life.

[0056] This system realizes precise control of the contact movement through intelligent algorithms, overcoming the defects of traditional mechanical arc extinguishing devices in terms of space limitation, structural complexity, and maintenance cost. The dynamic optimization and real-time adjustment of the contact movement trajectory ensure fast and effective arc extinguishing. At the same time, the multiple protection mechanisms and performance evaluation functions of the system ensure the safety and reliability of the equipment operation. The overall solution has the advantages of simple structure, strong adaptability, convenient maintenance, and precise control, providing an innovative solution for the arc extinguishing technology of disconnectors.

[0057] This technology realizes the arc extinguishing function through software algorithms instead of traditional mechanical devices, greatly reducing the equipment cost and structural complexity. The system can adaptively adjust the contact movement according to the real-time arc state, improving the arc extinguishing efficiency and extending the service life of the equipment. Generally speaking, this solution has significant advantages in terms of technological innovation, practical value, and economic benefits, providing a feasible way for the intelligent upgrade of disconnectors in the power system. Description of the Drawings

[0058] Figure 1 It is a schematic diagram of the process structure of the embodiment. Detailed Embodiment

[0059] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0060] As Figure 1 shown, a disconnector system based on dynamic contact control includes an arc detection unit, a contact motion control unit, a protection unit, and a performance evaluation unit.

[0061] The arc detection unit includes a current sensor, a voltage sensor, and an optical sensor. Among them, the current sensor is used to be arranged around the disconnector contact and collect the arc current i(t) in real time when the disconnector is separated. The voltage sensor is used to collect the arc voltage u arc (t) in real time. The optical sensor is used to detect the arc length l(t) and the spatial distribution state of the arc.

[0062] The contact motion control unit includes a servo motor and a motion controller. A plurality of servo motors are arranged and drive the contact to run according to the designed trajectory, and the maximum speed is set to V max . The motion controller is used to execute the trajectory planning algorithm, that is, to generate motion specified position and speed commands.

[0063] The protection unit includes an overcurrent protection element and a temperature detection element. Among them, the overcurrent protection element triggers an emergency stop when the current is too large, and the temperature detection element, that is, monitors the contact temperature T(t) through a thermocouple, and its threshold is T max = 150 °C.

[0064] The performance evaluation unit includes a data recording module and a life prediction module. The data recording module is used to store the arc extinction time t ext . The life prediction module is used to predict the remaining service life of the contact under the condition of multiple cumulative arc energies.

[0065] For the above units, in order to achieve precise control of the contact motion trajectory and speed, dynamic optimization and real-time control methods are used to efficiently extinguish the arc without a mechanical arc extinguishing device. The algorithm includes the following main steps: 1. Arc characteristic modeling: Describe the dynamic behavior of the arc through the arc characteristic equation. 2. Contact motion trajectory planning: Design the spatial motion trajectory of the contact, including three-dimensional path and speed planning. 3. Dynamic control strategy: Combine the real-time states of current and voltage to adjust the trajectory and speed. 4. Optimization and protection mechanism: Achieve the optimal performance through the optimization algorithm, and at the same time add multiple protection mechanisms to ensure safety. 5. Performance evaluation and feedback: Evaluate based on indicators such as arc extinction time, energy loss, and contact life.

[0066] Specifically as follows:

[0067] 1. Arc characteristic modeling. Arc characteristic modeling models and describes the generated arc state according to the information collected by the arc detection unit.

[0068] Among them, the dynamic behavior description equation of the arc is as follows:

[0069]

[0070] Among them, u arc (t) represents the voltage of the arc, which is measured by a voltage sensor and reflects the dynamic change of the resistance characteristics of the arc during the arc extinguishing process.

[0071] l(t) is the arc length, which is measured by an optical sensor. As the contact gradually separates, the arc length increases, resulting in an increase in the arc voltage.

[0072] i(t) is the arc current, which is measured by a current sensor. The change in current directly affects the arc maintenance condition; the exponent n (0.5 ≤ n ≤ 1.0) represents the non-linear effect of the control current on the arc voltage.

[0073] The coefficients A, B, C, and D are the characteristic parameters of the arc, which are related to the arc material, arc length, temperature, and humidity factors respectively.

[0074] Through the arc characteristic equation formula, the properties, state, current, and voltage magnitudes of the arc are modeled to obtain the arc characteristic model, which is convenient for subsequent adjustment of the contact motion state according to the arc state.

[0075] Among them, the formula for the generated arc power is as follows:

[0076]

[0077] Among them, the arc power P arc (t) is the instantaneous power consumed by the arc, which is directly related to the arc voltage u arc (t) and the arc current i(t). By reducing the arc power, the maintenance energy of the arc can be reduced, thereby accelerating the arc extinguishing.

[0078] According to the above arc power, calculate the total energy consumed by the arc, and its formula is as follows:

[0079]

[0080] Among them, W arc is the total energy consumed by the arc during the entire arc extinguishing process. The total arc energy W arc is a state description of the contact ablation degree. When W arc the energy is greater, it indicates that the contact loss is more serious.

[0081] Through the above formula, an arc characteristic model is established to describe the arc state information.

[0082] 2. Contact movement trajectory planning. Based on the above-mentioned arc state information, the specific operating state of the contact movement control unit is planned through the contact movement control unit.

[0083] The spatial trajectory planning formula of the contact is as follows:

[0084] ;

[0085] ;

[0086] .

[0087] Through the above formula, a three-dimensional coordinate is established to define the position state of the contact in three-dimensional space.

[0088] Among them, x0, y0, z0 (unit: m): Contact initial position coordinates.

[0089] R (unit: m): Horizontal movement trajectory radius.

[0090] ω (unit: rad / s): Angular velocity, controlling the horizontal movement frequency.

[0091] α, β (unit: s -1 ): Decay coefficients to ensure smooth convergence of the trajectory.

[0092] k (unit: m / s): Vertical movement rate.

[0093] Above, cos(ωt) and sin(ωt) define the rotation trajectory of the contact on the plane; R is the trajectory radius, controlling the rotation range; 1 - e -αt is an exponential decay function, restricting the rapid growth of the contact trajectory in the initial stage and gradually tending to be stable. As the contact separates, the arc path gradually lengthens, and the impedance of the arc increases, thereby reducing the arc power.

[0094] The above state describes the state when the contact separates. To improve the adaptability of the contact to different arc state characteristics and achieve an optimized arc extinguishing action, the present invention corrects the above trajectory, and the trajectory correction formula is as follows:

[0095] ;

[0096] ;

[0097] ;

[0098] .

[0099] Among them, S0 (unit: m): Initial correction amplitude; λ (unit: s -1): Correction attenuation coefficient; T (unit: s): Correction period; [n x , n y , n z : Unit vector of correction direction, determined by the arc position.

[0100] The above correction function S(t) enables the dynamic offset of the contact trajectory, which can better adapt to complex arc changes, such as arc reignition and other changing states.

[0101] S0*exp(-λt) sets the exponential decay term, making the correction amplitude gradually decrease with time. Since arc changes are generally more intense in the initial state, setting the exponential decay term can reduce the adjustment offset amplitude of the contact trajectory and adapt to the actual arc state changes.

[0102] sin(πt / T): The sine term introduces periodic changes, and the motion characteristics of the contact oscillating in the arc are described through the changes of the sine term.

[0103] Through the design of the contact motion trajectory planning, the motion of the contact is adjusted according to the arc characteristics, so as to achieve the optimal arc extinguishing effect.

[0104] 3. Speed optimization

[0105] Based on the arc characteristics, the contact motion speed needs to be adjusted according to different arc states. The specific formula is as follows:

[0106] ;

[0107] ;

[0108] .

[0109] Among them, V0 is the initial speed, and a is the acceleration. V max is the maximum speed, t1 is the time required to accelerate to V max , t2 is the duration of uniform motion, and t3 is the time required to decelerate to 0.

[0110] Through the segmented design of the contact speed, the arc path is quickly elongated in the acceleration stage to reduce the arc power, the stable operation is maintained in the uniform motion stage, and the structure is protected from impact in the deceleration stage.

[0111] Based on the above speed formula, the dynamic speed optimization formula is used to correct the above speed correspondingly:

[0112] ;

[0113] Among them, V opt(t): Optimized real-time contact speed (unit: m / s). Function: It represents the optimal contact movement speed dynamically adjusted according to the arc state and trajectory characteristics at time t.

[0114] V(t): Basic contact speed (unit: m / s). Function: The initially planned speed value, which may be generated based on segmented control (acceleration, constant speed, deceleration phases).

[0115] k V : Speed correction coefficient (dimensionless), used to adjust the speed according to the arc power and contact spacing.

[0116] Among them, the speed correction coefficient K V The calculation formula is as follows:

[0117] ;

[0118] Among them, P max : The maximum allowable arc power of the system (unit: W);

[0119] P arc (t): Real-time arc power (unit: W), calculated by P arc (t)=u arc (t)*i(t);

[0120] d(t): Current contact spacing (unit: m);

[0121] d crit : Critical safety spacing (unit: m), the minimum spacing that the contact needs to maintain to avoid arc reignition.

[0122] k p ,α,β: Experimentally calibrated coefficients (default values: k p =1.0,α=0.5,β=0.3).

[0123] k V Adjust the contact speed to adapt to the real-time state of the arc power P arc and the contact distance d. When P arc is large or d is close to the critical value d crit , increase the speed to accelerate the arc elongation.

[0124] K κ : Curvature correction coefficient, used to adjust the speed according to the contact trajectory curvature. The calculation formula is as follows:

[0125] ;

[0126] Among them, κ(t): Real-time curvature of the contact trajectory (unit: m -1 ), reflecting the degree of trajectory bending; κmax : Maximum allowable curvature (unit: m -1 ), determined by the structure limitation of the contact motion control unit; γ: Curvature decay exponent (default value: γ = 0.2).

[0127] Through the above curvature correction coefficient, the curvature κ(t) of the contact trajectory is restricted, making the contact motion dynamically smooth without drastic changes, and ensuring the safety and stability of the overall system while improving the arc extinguishing efficiency.

[0128] 4. Dynamic control strategy

[0129] Based on the above path planning and speed optimization status of the contact, a dynamic control algorithm is set, so that at each point position, the contact motion makes corresponding adjustments, and its state equation formula is as follows:

[0130] ;

[0131] The state vector x(t) includes the contact position d(t), speed V(t), arc current i(t), temperature T(t), and trajectory curvature κ(t), reflecting the dynamic state of the overall system.

[0132] The control law equation is as follows:

[0133] ;

[0134] Among them, K, N, G: Control gain matrix; r(t): Reference trajectory vector; S(t): Trajectory correction vector.

[0135] Through the above control law equation, the motion of the contact is adjusted by -K*x(t), and the contact is made to follow the planned trajectory by N*r(t); G*S(t) introduces a correction term to adapt to dynamic changes.

[0136] 5. Optimization and protection mechanism:

[0137] During the overall separation of the contact, in order to ensure the safety of the system, a corresponding protection mechanism is designed:

[0138] Overcurrent and overheat protection:

[0139] ;

[0140] Among them, k i represents the adjustment coefficient, used to define the safety threshold of the current.

[0141] I rated is the rated current, unit A.

[0142] T maxis the threshold temperature, in degrees Celsius, and is set to 150 °C in the present invention.

[0143] When the current i(t) or T(t) exceeds the threshold, a shutdown protection operation is triggered.

[0144] The dynamic characteristic equation of the contact is as follows:

[0145] ;

[0146] Where M: mass, representing the inertial characteristics of the system, in kg.

[0147] d²r / dt²: the second derivative of displacement r with respect to time, i.e., acceleration, in m / s².

[0148] C: damping coefficient, representing the energy dissipation characteristics of the system, in N·s / m.

[0149] dr / dt: the first derivative of displacement r with respect to time, i.e., velocity, in m / s. Describes the instantaneous velocity of the contact movement.

[0150] K: stiffness coefficient, representing the elastic restoring force characteristics of the system, in N / m.

[0151] r: displacement, describing the displacement of the contact in three-dimensional space, in m.

[0152] F: driving force, in N.

[0153] F s : trajectory correction force, in N..

[0154] In the above formula, the dynamic characteristic equation describes the mechanical state of the contact movement. During the contact movement, if an unstable state (such as too large oscillation amplitude or too fast speed) is detected, emergency braking or trajectory correction can be achieved by adjusting F or F s to avoid contact damage or arc deterioration.

[0155] 6. Performance evaluation and optimization

[0156] The arc extinction time, i.e., the arc quenching time t ext . The target is set as t ext ≤20 ms, and the formula is as follows:

[0157] ;

[0158] Where t ext : arc extinction time, referring to the time elapsed from the start of contact separation to the complete extinction of the arc. t f: The end time of the arc extinguishing process refers to the final moment when the arc is extinguished. t0: The start time of the arc extinguishing process refers to the moment when the contact breaking action begins.

[0159] According to the calculation of energy loss during arc extinguishing, the formula is as follows:

[0160] ;

[0161] Where, E loss : The total energy loss, which is the total energy consumption caused by the arc and current during the arc extinguishing process. P arc (t): The arc power, which is determined by the arc voltage and current; : The arc energy consumption, which is the total energy within the arc action time. : The current loss, which is the heat loss caused by the contact resistance R(t). i(t): The contact current; R(t): The variation of the contact resistance with time.

[0162] Based on the above arc energy loss formula, predict the contact life, and the formula is as follows:

[0163] ;

[0164] L: The remaining life of the contact, which predicts the service life of the contact according to the cumulative consumption of arc energy. L0: The initial rated life of the contact, which is the theoretical service life of the contact under standard working conditions. k: The reduction factor, which represents the influence degree of arc energy on the contact life and depends on the contact material. ∑W arc : The cumulative value of arc energy, which is the cumulative amount of the total arc energy during the arc extinguishing process: ; W rated : The rated energy bearing value of the contact, which refers to the total amount of arc energy that the contact can withstand during the designed service life.

[0165] Through the above formulas, quantify the arc extinguishing time, energy loss and contact life, so as to determine the optimization of the arc extinguishing process and the equipment maintenance time.

[0166] In summary, the intelligent arc extinguishing system of the disconnector based on contact dynamic control described in this specification realizes efficient arc extinguishing without an additional mechanical arc extinguishing device by introducing core technologies such as arc characteristic modeling, contact movement trajectory planning, dynamic control strategy, speed optimization and multiple protection mechanisms, and has remarkable technical effects.

[0167] First, through the dynamic modeling of state parameters such as arc voltage, current, and length, the present invention can accurately describe the arc characteristics and their variation laws, providing a basis for real-time optimization of the contact movement. This dynamic modeling method based on arc characteristics can not only effectively reduce the arc power and total energy loss, but also reduce the ablation degree of the contact material, fundamentally solving the space limitation problem faced by traditional arc extinguishing devices.

[0168] Secondly, by optimizing the contact movement trajectory and speed planning, the present invention adopts a motion model in three-dimensional space and an exponential decay trajectory correction algorithm to ensure that the contact can adapt to complex arc states during the switching operation. This design provides a large trajectory adjustment amplitude during the initial severe change stage of the arc, and realizes trajectory convergence when it gradually stabilizes in the later stage. It not only improves the arc extinguishing efficiency, but also enhances the smoothness of the contact movement, avoiding the phenomenon of arc reignition caused by vibration or trajectory deviation. In terms of dynamic control, the present invention combines the real-time arc state and precisely adjusts the contact movement through a control law. By introducing a correction coefficient for speed optimization, the contact speed can be dynamically adjusted according to the real-time states of the arc power and the contact spacing; at the same time, combined with curvature correction, the smoothness and safety of the contact movement trajectory are ensured. This control strategy effectively improves the response speed of the arc extinguishing action and the stability of the system operation, significantly superior to the passive control method of traditional arc extinguishing devices.

[0169] In addition, the present invention designs a multiple protection mechanism based on operating conditions such as overcurrent and overheating, which can trigger an emergency stop when the current or temperature exceeds the safety threshold, avoiding equipment damage due to overload or high temperature. At the same time, through the performance evaluation unit, quantitative analysis is carried out on the arc extinguishing time, energy loss, and contact life, providing data support for the maintenance and optimization of the equipment. This design of the full-process dynamic optimization and protection mechanism ensures the reliability and safety of the system.

[0170] The present invention overcomes the technical defects of space limitation and high maintenance cost of traditional arc extinguishing devices by dynamically controlling the movement trajectory and speed of the contact, and at the same time achieves the comprehensive technical effects of efficient arc extinguishing, low energy loss, and long contact life.

[0171] To better understand the technical objectives of the present invention, the following calculation examples are provided in this application:

[0172] 1. Initial parameter setting

[0173] Suppose in a certain disconnector opening operation, the system parameters are as follows:

[0174] Arc characteristic modeling:

[0175] A = 20V, B = 5V / m, C = 50V, D = 2V / m, n = 0.8

[0176] Initial arc length l(t) = 0.01 m, arc current i(t) = 100 A

[0177] Contact motion trajectory planning:

[0178] Initial position: x0 = 0 m, y0 = 0 m, z0 = 0 m

[0179] Trajectory radius R = 0.1 m, angular velocity ω = 10 rad / s

[0180] Decay coefficient α = 5 s -1 , β = 2 s -1 , vertical rate k = 0.5 m / s

[0181] Velocity optimization:

[0182] Maximum velocity V max = 2 m / s

[0183] Correction coefficients kp = 1.0, α = 0.5, β = 0.3

[0184] Critical safety spacing d crit = 0.2 m

[0185] Curvature correction parameter:

[0186] Maximum allowable curvature κ max = 1.0 m -1

[0187] Curvature decay exponent γ = 0.2

[0188] Dynamic control gain matrix:

[0189] K = [0.5, 0.1, 0.2, 0.05, 0.3]

[0190] N = [0.8, 0.2, 0.0, 0.0, 0.0]

[0191] G = [0.0, 0.0, 0.0, 0.0, 0.1]

[0192] Protection mechanism threshold:

[0193] Overcurrent protection threshold ki × i rated = 1.2 × 200 A = 240 A

[0194] Overheat protection threshold T max = 150 °C

[0195] Contact resistance model:

[0196] R(t) = R0 × (1 + γ × T(t)), where R0 = 0.01 Ω, γ = 0.003 °C -1

[0197] 2. Arc characteristic modeling and calculation

[0198] Step 1: Calculate the arc voltage u arc (t)

[0199] Take the arc length l(t) = 0.05m and current i(t) = 80A at t = 0.1s:

[0200] u arc (0.1) = 20 + 5×0.05 + (50 + 2×0.05) / 80^0.8

[0201] = 20.25 + 50.1 / 33.1 ≈ 21.76V

[0202] Step 2: Calculate the arc power P arc (t):

[0203] P arc (0.1) = u arc (0.1) × i(0.1) = 21.76 × 80 = 1740.8W

[0204] Step 3: Integrate to calculate the total arc energy W arc (Assume that P arc (t) linearly decreases within t ∈ [0, 0.02s]): W arc = 38J.

[0205] 3. Contact motion trajectory planning

[0206] Step 1: Calculate the uncorrected trajectory (t = 0.05s):

[0207] x(0.05) = 0 + 0.1×cos(0.5)×(1 - e^(-0.25)) ≈ 0.0194m

[0208] y(0.05) = 0 + 0.1×sin(0.5)×(1 - e^(-0.25)) ≈ 0.0106m

[0209] z(0.05) = 0 + 0.5×0.05×(1 - e^(-0.1)) ≈ 0.0024m

[0210] Step 2: Trajectory correction (S0 = 0.01m, λ = 10s -1 , T = 0.01s):

[0211] S(0.05) = 0.01×e^(-0.5)×sin(5π) = 0 → The corrected trajectory is the same as the original trajectory

[0212] 4. Velocity optimization

[0213] Step 1: Basic speed planning (acceleration phase t∈[0, 0.01s], a = 100m / s²):

[0214] V(0.005) = 0 + 100×0.005 = 0.5m / s

[0215] Step 2: Dynamic speed correction (assuming d(0.005) = 0.1m, P arc = 2000W):

[0216] k V = 1.0×(3000 / 2000)^0.5×(0.1 / 0.2)^0.3 ≈ 1.0

[0217] Step 3: Curvature correction (real-time curvature κ(t) = 0.8m -1 ):

[0218] k κ =(1.0 / 0.8)^0.2 ≈ 1.044

[0219] Step 4: Calculation of the optimized speed:

[0220] V opt (0.005) = min(0.5×1.0×1.044, 2.0) = 0.522m / s

[0221] 5. Implementation of the dynamic control strategy

[0222] Step 1: Update of the state vector (t = 0.1s):

[0223] x(t) = [0.15m, 1.5m / s, 120A, 130°C, 0.8m -1

[0224] Step 2: Calculation of the control law equation (reference trajectory r(t) = [0.2, 2.0, 0, 0, 0], correction vector S(t) = 0.01m):

[0225] u(t) = -[0.075, 0.15, 24, 6.5, 0.24] + [0.16, 0.4, 0, 0, 0] + [0, 0, 0, 0, 0.001] = [0.085, 0.25, -24, -6.5, -0.239]

[0226] Output command: Reduce the current by 24A and smooth the curvature by 0.239m -1 .

[0227] 6. Triggering of the protection mechanism

[0228] ​Scenario simulation: When t = 0.15 s, it is detected that i(t) = 250 A and T(t) = 160 °C

[0229] Trigger condition:

[0230] 250 A > 240 A and 160 °C > 150 °C

[0231] System response:

[0232] 1. Emergency stop the movement of the contact

[0233] 2. Start the cooling unit

[0234] 3. Record the fault event

[0235] 7. Performance evaluation

[0236] Step 1: Arc extinction time t ext

[0237] t ext = t f - t0 = 0.018 s - 0 s = 18 ms (satisfies t ext < 20 ms)

[0238] Step 2: Total energy loss E loss

[0239] Assume the contact resistance R(t) = 0.01×(1 + 0.003×130) = 0.0139 Ω:

[0240] E loss = 38 J (arc energy) + ∫(100 - 5000t)×0.0139dt ≈ 38 + 1.39 = 39.39 J.

[0241] Step 3: Prediction of contact life

[0242] L = 10 5 × exp(-0.1×38 / 1000) ≈ 10 5 × 0.996 = 99,600 times

[0243] 8. Summary of performance evaluation

[0244] Arc extinction time t ext = 18 ms < 20 ms;

[0245] Arc energy W arc = 38 J is minimized;

[0246] Total energy loss E loss = 39.39 J is minimized;

[0247] Contact life L = 99,600 times is close to 105 times

[0248] By dynamically controlling the strategy to adjust the contact trajectory and speed in real time, without additional arc extinguishing devices, the system can:

[0249] 1. Quick arc extinguishing: The arc extinguishing time is shortened to 18 ms, meeting the design requirements

[0250] 2. Low energy loss: The total energy loss is controlled within 39.39 J, significantly reducing contact ablation

[0251] 3. Long service life prediction: The remaining service life of the contact reaches 99,600 operations, approaching the initial rated service life. The dynamic control and protection mechanism effectively improve the safety and reliability of the system.

[0252] This specific embodiment is only an interpretation of the present invention and does not limit the present invention. After reading this specification, those skilled in the art can make modifications to this embodiment without creative contributions as needed, but as long as it is within the scope of the claims of the present invention, it is protected by the patent law.

Claims

1. A disconnector system based on dynamic contact control, characterized in that: include: An arc detection unit, the arc detection unit comprising a current sensor, a voltage sensor and an optical sensor, the current sensor is used to collect arc current, the voltage sensor is used to collect arc voltage, and the optical sensor is used to detect arc length and arc spatial distribution; A contact motion control unit, the contact motion control unit comprising a plurality of servo motors and a motion controller, the servo motors driving the contacts to run according to a designed trajectory, and the motion controller being used to execute a trajectory planning algorithm; The spatial trajectory planning algorithm of the contact is implemented by the following formula: x(t)=x0+R·cos(ωt)·(1-e -αt ); y(t)=y0+R·sin(ωt)·(1-e -αt ); z(t)=z0+k·t·(1-e -βt ); Among them, x0, y0, z0 are the coordinates of the initial position of the contact, R is the radius of the horizontal motion trajectory, ω is the angular velocity, α, β are the attenuation coefficients, and k is the vertical motion rate; The trajectory planning algorithm also includes a trajectory correction formula: x′(t)=x(t)+S(t)·n x ; y′(t)=y(t)+S(t)·n y ; z′(t)=z(t)+S(t)·n z ; Among them, S0 is the initial correction amplitude, λ is the correction attenuation coefficient, T is the correction period, [n x ,n y ,n z ] is the correction direction unit vector; A protection unit, the protection unit comprising an overcurrent protection element and a temperature detection element; A performance evaluation unit, comprising a data recording module and a life prediction module.

2. The isolating switch system according to claim 1, characterized in that: The arc characteristics detected by the arc detection unit are described by the following arc characteristic equation: Among them, u arc (t) represents the arc voltage, l(t) is the arc length, i(t) is the arc current, the index n ranges from 0.5≤n≤1.0, and the coefficients A, B, C, and D are arc characteristic parameters.

3. The isolating switch system according to claim 1, characterized in that: The movement speed state of the contact is controlled by the following formula: v(t)=v0+a·t, (0≤t≤t1); v(t)=v max ,(t1<t≤t2); v(t)=v max -a·(t-t2),(t2<t≤t3); Among them, V0 is the initial velocity, a is the acceleration, V max is the maximum speed, t1 is the acceleration to V max The time required, t2 is the duration of uniform motion, and t3 is the time required to decelerate to 0.

4. The isolating switch system according to claim 3, characterized in that: The contact movement speed is controlled by the following dynamic speed optimization formula: v opt (t)=min(v(t)·k v ·k κ ,v max ); Among them, V opt (t) is the optimized contact real-time speed, V(t) is the basic contact speed, k V is the speed correction factor, K κ is the curvature correction coefficient; The speed correction factor k V The calculation formula is: Among them, P max is the maximum arc power allowed by the system, Parc(t) is the real-time arc power, d(t) is the current contact distance, d crit is the critical safety distance, α, β are experimental calibration coefficients; The curvature correction coefficient K κ The calculation formula is: Among them, κ(t) is the real-time curvature of the contact trajectory, κ max is the maximum allowed curvature, and γ is the curvature attenuation exponent.

5. The isolating switch system according to claim 1, characterized in that: The overcurrent and overheat protection conditions of the protection unit are: i(t) > k i ·i rated or T(t) > T max ; Among them, k i is the adjustment coefficient, I rated is the rated current, T max is the threshold temperature, set to 150°C.

6. The isolating switch system according to claim 1, characterized in that: The contact dynamic characteristics are described by the following equation: Where M is the mass, C is the damping coefficient, K is the stiffness coefficient, r is the displacement, F is the driving force, F s is the trajectory correction force.

7. The isolating switch system according to claim 1, characterized in that: The arc extinguishing time t recorded by the performance evaluation unit ext Calculated by the following formula: t ext =t f -t0; Among them, t f is the end time of arc extinguishing process, t0 is the start time of arc extinguishing process, and the target is set to t ext ≤20ms; The energy loss is calculated according to the arc extinguishing state, the formula is as follows: E loss =∫P arc (t)dt+∫i 2 (t)·R(t)dt; Among them, E loss : Total energy loss, the total energy consumption caused by the arc and current during the arc extinguishing process, P arc (t): arc power, determined by arc voltage and current; ∫i 2 (t)·R(t)dt: Arc energy consumption, total energy during the arc action time, ∫i 2 (t)·R(t)dt: current loss, heat loss caused by contact resistance R(t), i(t): contact current; R(t): change of contact resistance over time.

8. The isolating switch system according to claim 7, characterized in that: The contact life prediction of the performance evaluation unit is calculated by the following formula: Where L is the remaining life of the contact, L0 is the initial rated life of the contact, k is the reduction factor, ∑W arc is the accumulated value of arc energy, W rated It is the rated energy bearing value of the contact.

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