Mobile energy storage ice melting system and method based on intelligent control of chopper circuit

Abstract

The invention discloses a mobile energy storage ice melting system and method based on intelligent control of a chopper circuit. The ice melting device comprises a switch module, a chopping ice melting module, an energy storage power supply module and a control module, the energy storage power supply module, the chopping ice melting module and the switch module are sequentially connected to form a loop, two ends of an ice coating line are connected to the loop, and the control module is used for calculating current needed by ice melting, calculating voltage needed by ice melting according to the current needed by ice melting and controlling the voltage needed by ice melting. According to the voltage required by ice melting and the actual output voltage of the chopping and ice melting module, the switch module is controlled to select the chopping and ice melting module to boost or buck; the total capacity required by ice melting in the ice melting process of the ice-coated line is calculated according to the current required by ice melting, and the capacity and the number of the energy storage power supply modules are selected according to the total capacity required by ice melting. The output current is direct current, an alternating current power supply does not need to be rectified into a direct current power supply through six-pulse wave or twelve-pulse wave rectification, and the advantages of being high in efficiency, small in size, easy to integrate and low in cost are achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of energy storage and direct current ice melting, and in particular relates to a mobile energy storage ice melting system and method based on chopper circuit intelligent control. Background Art

[0002] Icing on power lines not only seriously affects the normal operation of power transmission lines, but also causes significant losses to people’s lives. The hazards of icing on power lines are mainly reflected in tower collapse, line breakage, insulator flashover, conductor dancing, tripping, etc. In severe cases, it may even lead to power grid paralysis.

[0003] With the continued strengthening of the subtropical high pressure, the melting of Arctic sea ice and the transport of water vapor from the southwest Indian Ocean, the probability of cold waves will increase, which may easily lead to large-scale rain, snow and freezing disasters, and the problem of icing on power grid lines may become more prominent.

[0004] In order to reduce the impact of ice and snow disasters on power transmission lines and ensure the safe and smooth transmission of electric energy, various de-icing and ice-melting technologies have been studied. At present, there are dozens of ice-melting methods proposed, which are generally divided into the following categories according to their working principles: thermal ice-melting, mechanical de-icing, natural passive de-icing and other methods. The most efficient way to solve line icing is DC ice-melting, which is a technology that uses the heating effect of electric current to eliminate line icing by applying DC voltage and short-circuiting at the end of the transmission line. This technology melts the ice on the line by heating the conductor, avoiding the problem of line collapse and line breakage caused by icing.

[0005] At present, there are two installation methods for DC ice melting: fixed and mobile. Compared with fixed ice melting devices, mobile DC ice melting devices are light, small, and flexible, and are suitable for ice melting on lines of different voltage levels of 110 to 330 kV. Mobile DC ice melting can be divided into extended and active mobile types. The extended type is equipped with an extended ice melting device, which only needs to be connected to the power supply to reduce the purchase cost of ice melting equipment and improve economic efficiency; while the active mobile type is to install diesel generator sets, ice melting converter components and other equipment on a vehicle-mounted platform for mobile deployment. When melting ice, there is no need to take power from the outside to combine the ice melting device with the emergency vehicle. When not melting ice, it can also serve as a medium-voltage generator vehicle or a 400V generator vehicle.

[0006] However, the existing mobile DC ice melting device needs to use six-pulse or twelve-pulse rectification to rectify the AC power supply into DC power supply, which has low efficiency and complex structure. Therefore, it is necessary to invent a new mobile energy storage ice melting system and method. Summary of the invention

[0007] The purpose of the present invention is to solve the shortcomings of the above-mentioned background technology and provide a mobile energy storage ice melting system and method based on intelligent control of a chopper circuit. Since the current output by the mobile energy storage ice melting system is direct current, there is no need to use six-pulse or twelve-pulse rectification to rectify the AC power supply into a DC power supply, which has the advantages of high efficiency, small size, easy integration and low cost.

[0008] The technical solution adopted by the present invention is: a mobile energy storage ice melting system based on chopper circuit intelligent control, comprising:

[0009] The switch module, the chopper ice-melting module, the energy storage power module and the control module are connected in sequence to form a loop, and both ends of the ice-covering line are connected to the loop.

[0010] The control module is used to calculate the current required for ice melting, calculate the voltage required for ice melting according to the current required for ice melting, and control the switch module to select the voltage boost or voltage drop of the chopper ice melting module according to the voltage required for ice melting and the actual output voltage of the chopper ice melting module; calculate the total capacity required for ice melting in the ice melting process of the ice-covered line according to the current required for ice melting, and select the capacity and quantity of the energy storage power supply module according to the total capacity required for ice melting.

[0011] It also includes a data monitoring module, which is used to obtain information such as the outer diameter of the transmission line after ice coating, wind speed, length of the transmission line after ice coating, temperature difference between the inside of the transmission line after ice coating and the external environment, ice coating thickness, external temperature (ambient temperature), original transmission line diameter, etc.

[0012] Furthermore, the calculation of the current required for ice melting includes:

[0013] According to the two types of icing, rime and fog, the equivalent radiation conduction thermal resistance R is calculated respectively. Ts ,

[0014] Calculate the thermal resistance R Th ;

[0015] According to R Ts , R Th Calculate the current I required to melt ice rb ;

[0016] Current required for melting ice I rb Should be between the maximum ice melting current I max and minimum ice melting current I min If the current is too large, the line temperature will be higher than the maximum value allowed by the conductor, which may affect the line insulation; if the current is too small, it will not be sufficient to meet the ice melting requirements.

[0017] Control the current I required for ice melting rb Satisfy inequality I min <Irb max , where I min is the minimum ice melting current; I max is the maximum ice melting current.

[0018] Furthermore, if the environmental conditions form rime, the equivalent radiation conduction thermal resistance R is calculated using the following formula: Ts :

[0019]

[0020] If the environmental conditions form rime, the equivalent radiation conduction thermal resistance R is calculated using the following formula: Ts :

[0021]

[0022] Where D is the outer diameter of the transmission line after ice covering, in cm; V is the wind speed, in m / s.

[0023] Furthermore, rime is formed when the ambient temperature is between -5 and 0 degrees and the wind speed is between 1 and 20 m / s; and rime is formed when the temperature is between -13 and -3 degrees and the wind speed is between 1 and 20 m / s.

[0024] Further, the thermal conduction resistance R is calculated by the formula Th =L / (K*A), where L is the length of the transmission line after ice covering, in meters; K is the thermal conductivity, in W / cm2. Usually, the thermal conductivity of rime is 0.0012 W / cm2, and the thermal conductivity of rime is 0.0227 W / cm2; A is the cross-sectional area, in cm2. 2 ).

[0025] Furthermore, the current I required for ice melting is calculated by the following formula: rb :

[0026]

[0027] In the formula, I rb is the current required to melt the ice; R0 is the DC resistance at 0℃, in (Ω / m); T r is the time required for ice melting, in (h); Δt is the temperature difference between the inside of the transmission line and the external environment after ice covering, in (℃); R Th is the thermal conductivity resistance; R Ts is the equivalent radiation conduction thermal resistance; y is the specific gravity of ice, usually taken as 0.9; d is the original transmission line diameter, in (cm); b is the ice thickness, in (cm); D is the outer diameter of the transmission line after ice coating, in (cm).

[0028] ​Furthermore, the maximum and minimum ice melting currents are calculated using the following formula:

[0029] Maximum ice melting current:

[0030]

[0031] In the formula, I max is the maximum ice melting current, in A; R 90 The DC resistance at 90°C, in Ω / m; T 外 is the outside temperature, in (℃); d is the original transmission line diameter, in (cm);

[0032] Minimum ice melting current:

[0033]

[0034] In the formula, I min is the minimum ice-melting current, which is the minimum current to ensure that the original transmission line is not covered with ice, in (A); R0 is the DC resistance at 0℃, in (Ω / m); T b To ensure the minimum temperature without ice accumulation; T 外 is the outside temperature, in (℃); d is the original transmission line diameter, in (cm); D is the outer diameter of the transmission line after ice covering, in (cm); V is the wind speed, in (m / s).

[0035] Furthermore, the de-icing process of the ice-covered line includes: firstly, de-icing any two phases of the ice-covered line, and the de-icing current is I rb , the de-icing time is T1; then the two de-icing phases of the de-icing line are connected in parallel and then connected in series with the third phase to de-icing, so that the de-icing current on the third phase is also I rb , the ice melting time is T2.

[0036] Furthermore, the total capacity E required for ice melting is calculated by the following formula: 总 :

[0037]

[0038] Where r is the resistance per unit length of the line, in Ω / m; L is the length of the transmission line after ice covering, in m; E1 is the capacity during the ice melting time T1; and E2 is the capacity during the ice melting time T2.

[0039] Furthermore, the actual output voltage U o for:

[0040]

[0041] In the formula, t on is the conduction time; toff is the turn-off time; E is the power supply voltage of the chopper circuit; T is the period; α is the conduction ratio of the chopper circuit. Changing the conduction ratio α adjusts the output voltage. When 0<α<1 / 2, it is step-down, and when 1 / 2<α<1, it is step-up.

[0042] Furthermore, the voltage U required for ice melting 融 = Current required to melt ice I rb Equivalent resistance R of ice-covered circuit eq By adjusting the conduction ratio α of the chopper circuit, U 融 =U o Melt ice; when the voltage required for melting ice is U 融 ≥U o When the voltage required for melting ice is U 融 <U o When , the chopper circuit works in a step-down chopper (Buk) circuit.

[0043] The present invention also provides a mobile energy storage ice-melting method based on intelligent control of a chopper circuit, including calculating the current required for ice melting, calculating the voltage required for ice melting according to the current required for ice melting, and controlling a switch module to select voltage boost or voltage reduction of the chopper ice-melting module according to the voltage required for ice melting and the actual output voltage of the chopper ice-melting module; calculating the total capacity required for ice melting in the ice-melting process of the ice-covered line according to the current required for ice melting, and selecting the capacity and quantity of the energy storage power supply modules according to the total capacity required for ice melting.

[0044] Furthermore, the calculation of the current required for ice melting includes:

[0045] According to the two types of icing, rime and fog, the equivalent radiation conduction thermal resistance R is calculated respectively. Ts ,

[0046] Calculate the thermal resistance R Th ;

[0047] According to R Ts , R Th Calculate the current I required to melt ice rb ;

[0048] Current required for melting ice I rb Should be between the maximum ice melting current I max and minimum ice melting current I min If the current is too large, the line temperature will be higher than the maximum value allowed by the conductor, which may affect the line insulation; if the current is too small, it will not be sufficient to meet the ice melting requirements.

[0049] Control the current I required for ice melting rb Satisfy inequality I min <I rb <Imax , where I min is the minimum ice melting current; I max is the maximum ice melting current.

[0050] Furthermore, if the environmental conditions form rime, the equivalent radiation conduction thermal resistance R is calculated using the following formula: Ts :

[0051]

[0052] If the environmental conditions form rime, the equivalent radiation conduction thermal resistance R is calculated using the following formula: Ts :

[0053]

[0054] Where D is the outer diameter of the transmission line after ice covering, in cm; V is the wind speed, in m / s.

[0055] Furthermore, rime is formed when the ambient temperature is between -5 and 0 degrees and the wind speed is between 1 and 20 m / s; and rime is formed when the temperature is between -13 and -3 degrees and the wind speed is between 1 and 20 m / s.

[0056] Further, the thermal conduction resistance R is calculated by the formula Th =L / (K / A), where L is the length of the transmission line after ice covering, in meters; K is the thermal conductivity, in W / cm2. Usually, the thermal conductivity of rime is 0.0012 W / cm2, and the thermal conductivity of rime is 0.0227 W / cm2; A is the cross-sectional area, in cm2. 2 ).

[0057] The current I required for melting ice is calculated by the following formula rb :

[0058]

[0059] In the formula, I rb is the current required to melt the ice; R0 is the DC resistance at 0℃, in (Ω / m); T r is the time required for ice melting, in (h); Δt is the temperature difference between the inside of the transmission line and the external environment after ice covering, in (℃); R Th is the thermal conductivity resistance; R Ts is the equivalent radiation conduction thermal resistance; y is the specific gravity of ice, usually taken as 0.9; d is the original transmission line diameter, in (cm); b is the ice thickness, in (cm); D is the outer diameter of the transmission line after ice coating, in (cm).

[0060] Furthermore, the maximum and minimum ice melting currents are calculated using the following formula:

[0061] Maximum ice melting current:

[0062]

[0063] In the formula, I max is the maximum ice melting current, in A; R 90 The DC resistance at 90°C, in Ω / m; T 外 is the outside temperature, in (℃); d is the original transmission line diameter, in (cm);

[0064] Minimum ice melting current:

[0065] I min R0=[0.1432d+0.82(V*D) 3 / 4 ](T b -T 外 );

[0066] In the formula, I min is the minimum ice-melting current, which is the minimum current to ensure that the original transmission line is not covered with ice, in (A); R0 is the DC resistance at 0℃, in (Ω / m); T b To ensure the minimum temperature without ice accumulation; T 外 is the outside temperature, in (℃); d is the original transmission line diameter, in (cm); D is the outer diameter of the transmission line after ice covering, in (cm); V is the wind speed, in (m / s).

[0067] Furthermore, the de-icing process of the ice-covered line includes: firstly, de-icing any two phases of the ice-covered line, and the de-icing current is I rb , the de-icing time is T1; then the two de-icing phases of the de-icing line are connected in parallel and then connected in series with the third phase to de-icing, so that the de-icing current on the third phase is also I rb , the ice melting time is T2.

[0068] Furthermore, the total capacity E required for ice melting is calculated by the following formula: 总 :

[0069]

[0070] Where r is the resistance per unit length of the line, in Ω / m; L is the length of the transmission line after ice covering, in m; E1 is the capacity during the ice melting time T1; and E2 is the capacity during the ice melting time T2.

[0071] Furthermore, the actual output voltage U o for:

[0072]

[0073] In the formula, t on is the conduction time; t off is the turn-off time; E is the power supply voltage of the chopper circuit; T is the period; α is the conduction ratio of the chopper circuit. Changing the conduction ratio α adjusts the output voltage. When 0<α<1 / 2, it is step-down, and when 1 / 2<α<1, it is step-up.

[0074] Furthermore, the voltage U required for ice melting 融 = Current required to melt ice I rb Equivalent resistance R of ice-covered circuit eq By adjusting the conduction ratio α of the chopper circuit, U 融 =U o Melt ice; when the voltage required for melting ice is U 融 ≥U o When the voltage required for melting ice is U 融 <U o When , the chopper circuit works in a step-down chopper (Buk) circuit.

[0075] The mobile energy storage and ice-melting system based on intelligent control of a chopper circuit proposed in the present invention is equivalent to a large-capacity "ice-melting power bank". The principle is that the mobile energy storage and ice-melting system forms a controllable DC current on the ice-covered line through a chopper circuit according to resistivity, ambient temperature, wind speed, ice thickness, ice type and ice-melting time, and continuously converts the electric energy stored in the energy storage device into heat, thereby finally achieving ice melting. The current output by the present invention is DC, and there is no need to use six-pulse or twelve-pulse rectification to rectify the AC power supply into a DC power supply. It has the advantages of high efficiency, small size, easy integration and low cost.

[0076] The present invention can accurately adjust the electric heating power by accurately calculating the current and voltage required for ice melting, making the ice melting process more efficient; reasonable power regulation can ensure that energy is not wasted during the heating process, while avoiding overheating and causing equipment damage or excessive melting; avoid overheating and reduce the risk of system overload; more accurately control the ice melting time and temperature, thereby optimizing the effect; effectively reduce system failures and damage.

[0077] The present invention selects appropriate current, voltage and energy storage modules, and performs voltage step-up or voltage step-down regulation through a chopping module, which can dynamically adjust energy consumption according to demand and reduce unnecessary energy waste; in particular, when using chopping technology to adjust the voltage, efficient energy conversion can be achieved; energy consumption can be reduced and electricity costs can be saved; the overall energy utilization efficiency of the system can be improved; and efficient operation can be maintained under high load or low load conditions to avoid energy waste.

[0078] The present invention can prevent the system from being damaged or failing due to excessive current or voltage by calculating the required current and voltage and reasonably selecting appropriate equipment (such as a current control module and a chopper module); for example, overcurrent may cause overheating of wires or equipment, and overvoltage may damage electronic components; enhance the safety and reliability of equipment; reduce the risk of damage and failure of electrical equipment; and extend the service life of the system.

[0079] The present invention can ensure that the system can supply power stably under different working conditions by calculating the total capacity required for ice melting and selecting the appropriate capacity and number of energy storage power modules; reasonable capacity configuration can ensure that the energy storage system is not overcharged or over-discharged, thereby improving the working efficiency and life of the energy storage system; optimizing the configuration of the energy storage system to ensure sufficient power supply without overload; extending the service life of the energy storage battery and reducing the replacement cost; and improving the working efficiency and stability of the energy storage system.

[0080] The present invention can significantly reduce the failure and failure frequency of the system due to unreasonable design or unstable operation by accurately calculating the current, voltage and power requirements and rationally configuring the various modules of the system (such as power module, chopper module, energy storage module, etc.), thereby reducing the cost of repair and maintenance; reducing the system failure rate and the frequency of repairs; improving the long-term stability of the system and reducing maintenance costs; enhancing the reliability of equipment and reducing operational risks.

[0081] The present invention adopts a chopper module to perform voltage regulation (boost or buck), making the system more flexible, and can adjust the power output according to actual needs, so that the system parameters can be flexibly adjusted under different environments or different ice-melting needs; the system is more flexible and can adapt to different ice-melting environments or application needs; the system can be later upgraded or adjusted according to needs to meet the needs of higher efficiency or higher load; it is more adaptable to dynamically changing environmental conditions and ensures long-term stable operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0082] Figure 1 This is a schematic diagram of functional modules of a mobile energy storage and ice melting system based on intelligent control of a chopper circuit according to a first embodiment of the present invention;

[0083] Figure 2 A flow chart of a mobile energy storage ice melting method based on intelligent control of a chopper circuit according to a second embodiment of the present invention;

[0084] Figure 3 Schematic diagram of the chopper circuit of the present invention;

[0085] Figure 4 It is a schematic diagram of the battery cabinet in the energy storage power module of the present invention. DETAILED DESCRIPTION

[0086] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments to facilitate a clear understanding of the present invention, but they do not constitute a limitation on the present invention.

[0087] Embodiment 1

[0088] like Figure 1 As shown, the present invention provides a mobile energy storage ice melting system based on intelligent control of a chopper circuit, comprising:

[0089] The switch module 300, the chopper ice-melting module 200, the energy storage power module 100 and the control module are connected in sequence to form a loop, and both ends of the ice-covering line 400 are connected to the loop.

[0090] The control module is used to calculate the current required for ice melting, calculate the voltage required for ice melting according to the current required for ice melting, and control the switch module to select the voltage boost or voltage drop of the chopper ice melting module according to the voltage required for ice melting and the actual output voltage of the chopper ice melting module; calculate the total capacity required for ice melting in the ice melting process of the ice-covered line according to the current required for ice melting, and select the capacity and quantity of the energy storage power supply module according to the total capacity required for ice melting.

[0091] Calculation of the current required to melt ice includes:

[0092] According to the two types of icing, rime and fog, the equivalent radiation conduction thermal resistance R is calculated respectively. Ts ,

[0093] Calculate the thermal resistance R Th ;

[0094] According to R Ts , R Th Calculate the current I required to melt ice rb ;

[0095] Current required for melting ice I rb Should be between the maximum ice melting current I max and minimum ice melting current I min If the current is too large, the line temperature will be higher than the maximum value allowed by the conductor, which may affect the line insulation; if the current is too small, it will not be sufficient to meet the ice melting requirements.

[0096] Control the current I required for ice melting rb Satisfy inequality I min rb max , where I min is the minimum ice melting current; I max is the maximum ice melting current.

[0097] If the environmental conditions form rime, the equivalent radiation conduction thermal resistance R is calculated using the following formula: Ts :​​

[0098]

[0099] If the environmental conditions form rime, the equivalent radiation conduction thermal resistance R is calculated using the following formula: Ts :

[0100]

[0101] Where D is the outer diameter of the transmission line after ice covering, in cm; V is the wind speed, in m / s.

[0102] When the ambient temperature is -5 to 0 degrees and the wind speed is 1 to 20 m / s, rime is formed; when the temperature is -13 to -3 degrees and the wind speed is 1 to 20 m / s, rime is formed.

[0103] Calculate the thermal conductivity resistance R by the formula Th =L / (K*A), where L is the length of the transmission line after ice covering, in meters; K is the thermal conductivity, in W / cm2. Usually, the thermal conductivity of rime is 0.0012 W / cm2, and the thermal conductivity of rime is 0.0227 W / cm2; A is the cross-sectional area, in cm2. 2 ).

[0104] The current I required for melting ice is calculated by the following formula rb :

[0105]

[0106] In the formula, I rb is the current required to melt the ice; R0 is the DC resistance at 0℃, in (Ω / m); T r is the time required for ice melting, in (h); Δt is the temperature difference between the inside of the transmission line and the external environment after ice covering, in (℃); R Th is the thermal conductivity resistance; R Ts is the equivalent radiation conduction thermal resistance; y is the specific gravity of ice, usually taken as 0.9; d is the original transmission line diameter, in (cm); b is the ice thickness, in (cm); D is the outer diameter of the transmission line after ice coating, in (cm).

[0107] The maximum and minimum ice melting currents are calculated using the following formula:

[0108] Maximum ice melting current:

[0109]

[0110] In the formula, I max is the maximum ice melting current, in A; R 90 The DC resistance at 90°C, in Ω / m; T外 is the outside temperature, in (℃); d is the original transmission line diameter, in (cm);

[0111] Minimum ice melting current:

[0112] I min R0=[0.1432Σd+0.82(V*D) 3 / 4 ](T b -T 外 );

[0113] In the formula, I min is the minimum ice-melting current, which is the minimum current to ensure that the original transmission line is not covered with ice, in (A); R0 is the DC resistance at 0℃, in (Ω / m); T b To ensure the minimum temperature without ice accumulation; T 外 is the outside temperature, in (℃); d is the original transmission line diameter, in (cm); D is the outer diameter of the transmission line after ice covering, in (cm); V is the wind speed, in (m / s).

[0114] There are two conventional ice-melting methods. The first ice-melting method includes: first short-circuiting the three-phase ends of the line together, and then selecting two phases (such as phase A and phase B) to connect to the positive and negative poles of the DC power supply to melt the ice. After the ice-melting is completed, the other two phases (such as phase B and phase C) are selected to connect to the positive and negative poles of the DC power supply to melt the ice; the second ice-melting method includes: first short-circuiting the three-phase ends of the line together, and then selecting two phases (such as phase A and phase C) in parallel to connect one end of the DC power supply to the AC parallel end, and connecting the other end of the DC power supply to the B end, and then exchanging two phases (such as phase A and phase B) in parallel and then connecting them in series with the C end, and finally exchanging two phases (such as phase B and phase C) in parallel and then connecting them in series with the A end, and the ice-melting operation is achieved through three steps.

[0115] The de-icing process of the ice-covered line in this embodiment includes: firstly, de-icing any two phases of the ice-covered line, and the de-icing current is I rb , the de-icing time is T1; then the two de-icing phases of the de-icing line are connected in parallel and then connected in series with the third phase to de-icing, so that the de-icing current on the third phase is also I rb , the ice melting time is T2.

[0116] The total capacity E required for ice melting is calculated by the following formula 总 :

[0117]

[0118] Where r is the resistance per unit length of the line, in Ω / m; L is the length of the transmission line after ice covering, in m; E1 is the capacity during the ice melting time T1; and E2 is the capacity during the ice melting time T2.

[0119] The chopper circuit is controlled according to the current required for ice melting, so that its output size can meet the current required for ice melting. Therefore, when designing the chopper circuit, it is necessary to consider both the step-up chopper circuit and the step-down chopper circuit. The design principle is as follows: Figure 3 As shown: the chopper circuit includes a power supply E, a switching tube V, an inductor L, a diode VD, a capacitor C, and a load R. The positive electrode of the power supply E is connected to one end of the switching tube V, the other end of the switching tube V is connected to the cathode of the diode VD, the anode of the diode VD is connected to one end of the load R, the negative electrode of the power supply E is connected to the other end of the load R, one end of the inductor L is connected to the cathode of the diode VD, and the other end is connected to the negative electrode of the power supply E, and the capacitor C is connected in parallel with the load R.

[0120] When V is turned on, the power supply E supplies power to L through V to store energy. At this time, the current is i1. At the same time, C maintains a constant output voltage and supplies power to the load R. When V is turned off, the energy of L is released to the load. The current is i2. The polarity of the load voltage is negative at the top and positive at the bottom, which is opposite to the polarity of the power supply voltage. This circuit is also called a reverse polarity chopper circuit. When V is in the on state, u L =E; and when V is in the off state, u L =-u o , the actual output voltage of the chopper ice melting module is U o for:

[0121]

[0122] In the formula, t on is the conduction time; t off is the turn-off time; E is the power supply voltage of the chopper circuit; T is the period; α is the conduction ratio of the chopper circuit. Changing the conduction ratio α adjusts the output voltage. When 0<α<1 / 2, it is step-down, and when 1 / 2<α<1, it is step-up.

[0123] Voltage U required for ice melting 融 = Current required to melt ice I rb Equivalent resistance R of ice-covered circuit eq By adjusting the conduction ratio α of the chopper circuit, U 融 =U o Melt ice; when the voltage required for melting ice is U 融 ≥U o When the voltage required for melting ice is U 融 <U o When , the chopper circuit works in a step-down chopper (Buk) circuit.

[0124] The energy storage power module includes a battery module management unit, a battery cabinet management unit, a battery stack monitoring unit, etc., and is mainly composed of ternary lithium batteries. The energy storage power module is required to meet the current I required for ice melting. rbTotal capacity E required for ice melting 总 By designing several battery cabinets, each battery cabinet is composed of several battery cells connected in series and parallel. The battery cabinet is constructed as follows Figure 4 The way of composition.

[0125] Embodiment 2

[0126] like Figure 2 As shown, the present invention also provides a mobile energy storage ice-melting method based on intelligent control of a chopper circuit, including calculating the current required for ice melting, calculating the voltage required for ice melting according to the current required for ice melting, and controlling a switch module to select the chopper ice-melting module to increase or decrease the voltage according to the voltage required for ice melting and the actual output voltage of the chopper ice-melting module; calculating the total capacity required for ice melting in the ice-melting process of the ice-covered line according to the current required for ice melting, and selecting the capacity and number of energy storage power supply modules according to the total capacity required for ice melting.

[0127] Calculation of the current required to melt ice includes:

[0128] According to the two types of icing, rime and fog, the equivalent radiation conduction thermal resistance R is calculated respectively. Ts ,

[0129] Calculate the thermal resistance R Th ;

[0130] According to R Ts , R Th Calculate the current I required to melt ice rb ;

[0131] Current required for melting ice I rb Should be between the maximum ice melting current I max and minimum ice melting current I min If the current is too large, the line temperature will be higher than the maximum value allowed by the conductor, which may affect the line insulation; if the current is too small, it will not be sufficient to meet the ice melting requirements.

[0132] Control the current I required for ice melting rb Satisfy inequality I min <I rb <I max , where I min is the minimum ice melting current; I max is the maximum ice melting current.

[0133] If the environmental conditions form rime, the equivalent radiation conduction thermal resistance R is calculated using the following formula: Ts :

[0134]

[0135] If the environmental conditions form rime, the equivalent radiation conduction thermal resistance R is calculated using the following formula: Ts :

[0136]

[0137] Where D is the outer diameter of the transmission line after ice covering, in cm; V is the wind speed, in m / s.

[0138] When the ambient temperature is -5 to 0 degrees and the wind speed is 1 to 20 m / s, rime is formed; when the temperature is -13 to -3 degrees and the wind speed is 1 to 20 m / s, rime is formed.

[0139] Calculate the thermal conductivity resistance R by the formula Th =L / (K*A), where L is the length of the transmission line after ice covering, in meters; K is the thermal conductivity, in W / cm2. Usually, the thermal conductivity of rime is 0.0012 W / cm2, and the thermal conductivity of rime is 0.0227 W / cm2; A is the cross-sectional area, in cm2. 2 ).

[0140] The current I required for melting ice is calculated by the following formula rb :

[0141]

[0142] In the formula, I rb is the current required to melt the ice; R0 is the DC resistance at 0℃, in (Ω / m); T r is the time required for ice melting, in (h); Δt is the temperature difference between the inside of the transmission line and the external environment after ice covering, in (℃); R Th is the thermal conductivity resistance; R Ts is the equivalent radiation conduction thermal resistance; y is the specific gravity of ice, usually taken as 0.9; d is the original transmission line diameter, in (cm); b is the ice thickness, in (cm); D is the outer diameter of the transmission line after ice coating, in (cm).

[0143] The maximum and minimum ice melting currents are calculated using the following formula:

[0144] Maximum ice melting current:

[0145]

[0146] In the formula, I max is the maximum ice melting current, in A; R 90 The DC resistance at 90°C, in Ω / m; T 外 is the outside temperature, in (℃); d is the original transmission line diameter, in (cm);

[0147] Minimum ice melting current:

[0148] Imin R0=[0.143Σd+0.82(V*D) 3 / 4 ](T b -T 外 );

[0149] In the formula, I min is the minimum ice-melting current, which is the minimum current to ensure that the original transmission line is not covered with ice, in (A); R0 is the DC resistance at 0℃, in (Ω / m); T b To ensure the minimum temperature without ice accumulation; T 外 is the outside temperature, in (℃); d is the original transmission line diameter, in (cm); D is the outer diameter of the transmission line after ice covering, in (cm); V is the wind speed, in (m / s).

[0150] There are two conventional ice-melting methods. The first ice-melting method includes: first short-circuiting the three-phase ends of the line together, and then selecting two phases (such as phase A and phase B) to connect to the positive and negative poles of the DC power supply to melt the ice. After the ice-melting is completed, the other two phases (such as phase B and phase C) are selected to connect to the positive and negative poles of the DC power supply to melt the ice; the second ice-melting method includes: first short-circuiting the three-phase ends of the line together, and then selecting two phases (such as phase A and phase C) in parallel to connect one end of the DC power supply to the AC parallel end, and connecting the other end of the DC power supply to the B end, and then exchanging two phases (such as phase A and phase B) in parallel and then connecting them in series with the C end, and finally exchanging two phases (such as phase B and phase C) in parallel and then connecting them in series with the A end, and the ice-melting operation is achieved through three steps.

[0151] The de-icing process of the ice-covered line in this embodiment includes: firstly, de-icing any two phases of the ice-covered line, and the de-icing current is I rb , the de-icing time is T1; then the two de-icing phases of the de-icing line are connected in parallel and then connected in series with the third phase to de-icing, so that the de-icing current on the third phase is also I rb , the ice melting time is T2.

[0152] The total capacity E required for ice melting is calculated by the following formula 总 :

[0153]

[0154] Where r is the resistance per unit length of the line, in Ω / m; L is the length of the transmission line after ice covering, in m; E1 is the capacity during the ice melting time T1; and E2 is the capacity during the ice melting time T2.

[0155] The chopper circuit is controlled according to the current required for ice melting, so that its output size can meet the current required for ice melting. Therefore, when designing the chopper circuit, it is necessary to consider both the step-up chopper circuit and the step-down chopper circuit. The design principle is as follows: Figure 3As shown: the chopper circuit includes a power supply E, a switching tube V, an inductor L, a diode VD, a capacitor C, and a load R. The positive electrode of the power supply E is connected to one end of the switching tube V, the other end of the switching tube V is connected to the cathode of the diode VD, the anode of the diode VD is connected to one end of the load R, the negative electrode of the power supply E is connected to the other end of the load R, one end of the inductor L is connected to the cathode of the diode VD, and the other end is connected to the negative electrode of the power supply E, and the capacitor C is connected in parallel with the load R.

[0156] When V is turned on, the power supply E supplies power to L through V to store energy. At this time, the current is i1. At the same time, C maintains a constant output voltage and supplies power to the load R. When V is turned off, the energy of L is released to the load. The current is i2. The polarity of the load voltage is negative at the top and positive at the bottom, which is opposite to the polarity of the power supply voltage. This circuit is also called a reverse polarity chopper circuit. When V is in the on state, u L =E; and when V is in the off state, u L =-u o , the actual output voltage of the chopper ice melting module is U o for:

[0157]

[0158] In the formula, t on is the conduction time; t off is the turn-off time; E is the power supply voltage of the chopper circuit; T is the period; α is the conduction ratio of the chopper circuit. Changing the conduction ratio α adjusts the output voltage. When 0<α<1 / 2, it is step-down, and when 1 / 2<α<1, it is step-up.

[0159] Voltage U required for ice melting 融 = Current required to melt ice I rb Equivalent resistance R of ice-covered circuit eq By adjusting the conduction ratio α of the chopper circuit, U 融 =U o Melt ice; when the voltage required for melting ice is U 融 ≥U o When the voltage required for melting ice is U 融 <U o When , the chopper circuit works in a step-down chopper (Buk) circuit.

[0160] When ice melting is not needed, the energy storage battery in the energy storage power module needs to be fully charged. After ice melting is completed, it also needs to be fully charged in order to prepare for the next ice melting operation.

[0161] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0162] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0163] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0164] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0165] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit its protection scope. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that after reading the present invention, those skilled in the art can still make various changes, modifications or equivalent substitutions to the specific implementation methods of the invention, but these changes, modifications or equivalent substitutions are all within the protection scope of the pending claims of the invention.

[0166] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

Claims

1. A mobile energy storage ice melting system based on chopper circuit intelligent control, characterized in that: It includes a switch module, a chopper ice-melting module, an energy storage power module and a control module. The energy storage power module, the chopper ice-melting module and the switch module are connected in sequence to form a loop. Both ends of the ice-covering line are connected to the loop. The control module is used to calculate the current required for ice melting, calculate the voltage required for ice melting according to the current required for ice melting, and control the switch module to select the voltage boost or voltage drop of the chopper ice melting module according to the voltage required for ice melting and the actual output voltage of the chopper ice melting module; calculate the total capacity required for ice melting in the ice melting process of the ice-covered line according to the current required for ice melting, and select the capacity and quantity of the energy storage power supply module according to the total capacity required for ice melting.

2. According to claim 1, a mobile energy storage and ice melting system based on intelligent control of a chopper circuit is characterized in that: Calculation of the current required to melt ice includes: According to the two types of icing, rime and fog, the equivalent radiation conduction thermal resistance R is calculated respectively. Ts , Calculate the thermal resistance R Th ; According to R Ts , R Th Calculate the current I required to melt ice rb ; Control the current I required for ice melting rb Satisfy inequality I min <I rb <I max , where I min is the minimum ice melting current; I max is the maximum ice melting current.

3. According to claim 2, a mobile energy storage and ice melting system based on intelligent control of a chopper circuit is characterized in that: If the environmental conditions form rime, the equivalent radiation conduction thermal resistance R is calculated using the following formula: Ts : If the environmental conditions form rime, the equivalent radiation conduction thermal resistance R is calculated using the following formula: Ts : Where D is the outer diameter of the transmission line after ice covering; V is the wind speed.

4. According to claim 3, a mobile energy storage and ice melting system based on intelligent control of a chopper circuit is characterized in that: When the ambient temperature is -5 to 0 degrees and the wind speed is 1 to 20 m / s, rime is formed; when the temperature is -13 to -3 degrees and the wind speed is 1 to 20 m / s, rime is formed.

5. According to claim 2, a mobile energy storage ice melting system based on chopper circuit intelligent control is characterized in that: Calculate the thermal conductivity resistance R by the formula Th =L / (K*A), where L is the length of the transmission line after ice covering; K is the thermal conductivity, usually the thermal conductivity of rime is 0.0012W / cm, and the thermal conductivity of rime is 0.0227W / cm; A is the cross-sectional area.

6. The mobile energy storage and ice melting system based on chopper circuit intelligent control according to claim 2 is characterized in that: The current I required for melting ice is calculated by the following formula rb : In the formula, I rb is the current required to melt the ice; R0 is the DC resistance at 0℃; T r is the time required for ice melting; Δt is the temperature difference between the inside of the transmission line and the external environment after ice covering; R Th is the thermal conductivity resistance; R Ts is the equivalent radiation conduction thermal resistance; y is the specific gravity of ice; d is the original transmission line diameter; b is the ice thickness; D is the outer diameter of the transmission line after ice coating.

7. The mobile energy storage and ice melting system based on chopper circuit intelligent control according to claim 2 is characterized by: The maximum and minimum ice melting currents are calculated using the following formula: Maximum ice melting current: In the formula, I max is the maximum ice melting current; R 90 DC resistance at 90℃; T 外 is the outside temperature; d is the original transmission line diameter; Minimum ice melting current: I min R0=[0.143∑d+0.82(V*D) 3 / 4 ](T b -T 外 ); In the formula, I min is the minimum ice melting current; R0 is the DC resistance at 0℃; T b To ensure the minimum temperature without ice accumulation; T 外 is the outside temperature; d is the original transmission line diameter; D is the outer diameter of the transmission line after ice covering; V is the wind speed.

8. The mobile energy storage and ice melting system based on chopper circuit intelligent control according to claim 1 is characterized in that: The de-icing process of the ice-covered line includes: firstly, de-icing any two phases of the ice-covered line, and the de-icing current is I rb , the de-icing time is T1; then the two de-icing phases of the de-icing line are connected in parallel and then connected in series with the third phase to de-icing, so that the de-icing current on the third phase is also I rb , the ice melting time is T2.

9. The mobile energy storage and ice melting system based on chopper circuit intelligent control according to claim 2 is characterized by: The total capacity E required for ice melting is calculated by the following formula 总 : Where r is the resistance per unit length of the line; L is the length of the transmission line after ice covering; E1 is the capacity during the ice melting time T1; and E2 is the capacity during the ice melting time T2.

10. The mobile energy storage and ice melting system based on chopper circuit intelligent control according to claim 2 is characterized in that: Voltage U required for ice melting 融 = Current required to melt ice I rb Equivalent resistance R of ice-covered circuit eq By adjusting the conduction ratio α of the chopper circuit, U 融 =U o Melt ice; when the voltage required for melting ice is U 融 ≥U o When the voltage U required for melting ice is 融 <U o When , the chopper circuit works as a step-down chopper circuit.

11. A mobile energy storage ice melting method based on chopper circuit intelligent control, characterized in that: The method includes calculating the current required for ice melting, calculating the voltage required for ice melting according to the current required for ice melting, and controlling the switch module to select the voltage boost or voltage drop of the chopper ice melting module according to the voltage required for ice melting and the actual output voltage of the chopper ice melting module; calculating the total capacity required for ice melting in the ice melting process of the ice-covered line according to the current required for ice melting, and selecting the capacity and quantity of the energy storage power supply modules according to the total capacity required for ice melting.

12. The mobile energy storage and ice melting method based on chopper circuit intelligent control according to claim 11, characterized in that: Calculation of the current required to melt ice includes: According to the two types of icing, rime and fog, the equivalent radiation conduction thermal resistance R is calculated respectively. Ts , Calculate the thermal resistance R Th ; According to R Ts , R Th Calculate the current I required to melt ice rb ; Control the current I required for ice melting rb Satisfy inequality I min >I rb >I max , where I min is the minimum ice melting current; I max is the maximum ice melting current.

13. The mobile energy storage and ice melting method based on chopper circuit intelligent control according to claim 12, characterized in that: If the environmental conditions form rime, the equivalent radiation conduction thermal resistance R is calculated using the following formula: Ts : If the environmental conditions form rime, the equivalent radiation conduction thermal resistance R is calculated using the following formula: Ts : Where D is the outer diameter of the transmission line after ice covering; V is the wind speed.

14. The mobile energy storage and ice melting method based on chopper circuit intelligent control according to claim 13, characterized in that: When the ambient temperature is -5 to 0 degrees and the wind speed is 1 to 20 m / s, rime is formed; when the temperature is -13 to -3 degrees and the wind speed is 1 to 20 m / s, rime is formed.

15. The mobile energy storage and ice melting method based on chopper circuit intelligent control according to claim 12, characterized in that: Calculate the thermal conductivity resistance R by the formula Th =L / (K*A), where L is the length of the transmission line after ice covering; K is the thermal conductivity, usually the thermal conductivity of rime is 0.0012W / cm, and the thermal conductivity of rime is 0.0227W / cm; A is the cross-sectional area.

16. The mobile energy storage and ice melting method based on chopper circuit intelligent control according to claim 12, characterized in that: The current I required for melting ice is calculated by the following formula rb : In the formula, I rb is the current required to melt the ice; R0 is the DC resistance at 0℃; T r is the time required for ice melting; Δt is the temperature difference between the inside of the transmission line and the external environment after ice covering; R Th is the thermal conductivity resistance; R Ts is the equivalent radiation conduction thermal resistance; y is the specific gravity of ice; d is the original transmission line diameter; b is the ice thickness; D is the outer diameter of the transmission line after ice coating.

17. The mobile energy storage and ice melting method based on chopper circuit intelligent control according to claim 12, characterized in that: The maximum and minimum ice melting currents are calculated using the following formula: Maximum ice melting current: In the formula, I max is the maximum ice melting current; R 90 DC resistance at 90℃; T 外 is the outside temperature; d is the original transmission line diameter; Minimum ice melting current: I min R0=[0.143∑d+0.82(V*D) 3 / 4 ](T b -T 外 ); In the formula, I min is the minimum ice melting current; R0 is the DC resistance at 0℃; T b To ensure the minimum temperature without ice accumulation; T 外 is the outside temperature; d is the original transmission line diameter; D is the outer diameter of the transmission line after ice covering; V is the wind speed.

18. The mobile energy storage and ice melting method based on chopper circuit intelligent control according to claim 11, characterized in that: The de-icing process of the ice-covered line includes: firstly, de-icing any two phases of the ice-covered line, and the de-icing current is I rb , the de-icing time is T1; then the two de-icing phases of the de-icing line are connected in parallel and then connected in series with the third phase to de-icing, so that the de-icing current on the third phase is also I rb , the ice melting time is T2.

19. The mobile energy storage and ice melting method based on chopper circuit intelligent control according to claim 12, characterized in that: The total capacity E required for ice melting is calculated by the following formula 总 : Where r is the resistance per unit length of the line; L is the length of the transmission line after ice covering; E1 is the capacity during the ice melting time T1; and E2 is the capacity during the ice melting time T2.

20. The mobile energy storage and ice melting method based on chopper circuit intelligent control according to claim 12, characterized in that: Voltage U required for ice melting 融 = Current required to melt ice I rb Equivalent resistance R of ice-covered circuit eq By adjusting the conduction ratio α of the chopper circuit, U 融 =U o Melt ice; when the voltage required for melting ice is U 融 ≥U o When the voltage U required for melting ice is 融 <U o When , the chopper circuit works as a step-down chopper circuit.

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