Reconfigurable charging pile multi-mode output circuit

Abstract

The invention discloses a reconfigurable charging pile multi-mode output circuit. The reconfigurable charging pile multi-mode output circuit comprises n modular converters with rated power of P and an output distribution matrix circuit, n paths of row lines of the output distribution matrix circuit of the reconfigurable charging pile are respectively connected with n modular converters with rated power of P, n paths of column lines are respectively connected with n paths of load output ports of the charging pile, and electric switches are arranged at cross points of some row lines and column lines; and the n modular converters can output in any combination by controlling the electrical switch. Through the output distribution matrix circuit and the scheduling strategy thereof, the reconfigurable charging pile can realize any power output from 1P to nP, the number of output paths can be 1-n, idle waste of equipment is not caused, and used wires and electrical switches are most saved.

Description

Technical Field

[0001] This invention belongs to the field of new energy electric vehicle charging piles and relates to a reconfigurable charging pile multi-mode output circuit. Background Technology

[0002] Existing DC charging piles have a wide range of power ratings, from approximately 10kW to 480kW. Driven by the new national standard GB / T 20234.3-2023 "Connecting Devices for Conductive Charging of Electric Vehicles Part 3: DC Charging Interface" released in September 2023, the charging power of future DC charging piles may reach 1200kW. Compared to gasoline vehicles, electric vehicles have a longer charging time. To compensate for this, the industry is currently experiencing a surge in interest in DC fast charging. The advantage of DC fast charging piles is their short charging time. Currently, super-fast charging piles can charge a battery to 80% of its rated capacity within 10 minutes, allowing an electric vehicle to travel 300-400 kilometers. However, DC fast charging piles also have the following disadvantages: 1. Instantaneous high-power charging has a significant impact on the power grid, which is detrimental to the safe and stable operation of the grid; 2. High-power fast charging also has a certain adverse effect on battery life; 3. Excessive power peaks can also increase grid connection costs. In reality, electric vehicle users have diverse needs and don't need to blindly pursue fast charging. When time is extremely tight, fast charging is an option; when there is ample time, slow charging is more advantageous. Charging stations should provide charging power commensurate with the user's allowed charging time to achieve maximum overall efficiency. However, existing charging station output modes are relatively singular and cannot meet the diverse needs of users. Existing fast charging stations generally can only output a single rated power; if a lower power output is required, it needs to be derated, resulting in idle and wasted equipment. Existing slow charging stations can also only output rated power and cannot be combined to output higher power. Summary of the Invention

[0003] The purpose of this invention and the technical problem it aims to solve:

[0004] To address the contradiction between the single output mode of existing charging piles and the diverse needs of users, this invention proposes a reconfigurable charging pile, which includes n modular converters (n is a positive integer) and an output distribution matrix circuit. Each modular power supply has a rated power of P. This reconfigurable charging pile can achieve arbitrary power output from 1P to nP, and the number of output channels can be from 1 to n, without causing idle waste of equipment, and with minimal use of wiring and relays.

[0005] Technical principles and solutions of this invention:

[0006] The reconfigurable charging pile multi-mode output circuit proposed in this invention includes n modular converters and an output distribution matrix circuit. For example...Figure 1 The inputs of these n modular converters are connected to the input power supply of the charging pile, and the voltage of the charging pile's input power supply is represented by u. d This means that if the charging pile's input power is DC, the modular converter is a DC-DC converter; if the charging pile's input power is AC, the modular converter is an AC-DC converter. These n modular converters have n outputs, each connected to one of the n inputs of the output distribution matrix circuit (i.e., the row lines of the matrix circuit). The output distribution matrix circuit also has n outputs (i.e., the column lines of the matrix circuit), each connected to one of the n load output ports of the charging pile. Each row and column line of the matrix circuit represents a set of power lines. Typically, a set of power lines consists of one positive and one negative power line. There is no electrical connection at the intersection of the row and column lines; the row and column lines need to be electrically connected or disconnected using an electrical switch. A common type of electrical switch is a double-pole single-throw relay. Figure 1 The simplified switch symbol is used to represent the double-pole single-throw relay.

[0007] The output distribution matrix circuit of the reconfigurable charging pile has n row lines connected to n modular converters with a rated power of P, and n column lines connected to the n load output ports of the charging pile. Electrical switches are installed at some intersections of the row and column lines, allowing the n modular converters to be combined in any way by controlling these switches. Through the output distribution matrix circuit and its scheduling strategy, the reconfigurable charging pile can achieve arbitrary power output from 1P to nP, with 1 to n output channels, without causing any idle or wasted equipment.

[0008] The requirement for optimizing the output distribution matrix circuit is to minimize the power rating of the wires in the matrix circuit (i.e., to minimize wiring) and the number of electrical switches while ensuring the maximum number of output modes. Since the power rating of the row lines connecting the modular converter is already determined as P, the ultimate problem in optimizing the output distribution matrix circuit is to determine the power rating P of the n column lines. R,k and the number N of electrical switches required in each column k Given subscripts k=1,2,…,n, the following relationship exists between two quantities: P R,k =N k P.

[0009] The above engineering problem can be described by the following mathematical model. Let P be the output power of the k-th load output port of the output distribution matrix circuit in a certain output mode. k =x k P, x k If the integer is 0 or a positive integer, the following formula can be obtained:

[0010] (1)

[0011] (2)

[0012] The above constraint (1) is an n-variable linear equation. A set of solutions that satisfy constraints (1) and (2) is one output mode of the reconfigurable charging pile. The power level P of the k-th column line R,k P must be satisfied R,k ≥x k,max P, take P R,k =x k,max P can minimize the amount of wire and electrical switches used, where x k,max For all solutions that satisfy constraints (1) and (2), x k The maximum value of x. Therefore, it is only necessary to determine x according to the equation. k,max This allows us to determine the power level P of the n columns. R,k and the number N of electrical switches required in each column k This means that the optimized design of the output distribution matrix circuit has been completed.

[0013] Based on the constraints, we can deduce x. k,max From equations (1) and (2), we can obtain:

[0014] (3)

[0015] We can obtain: (4)

[0016] Therefore: (5)

[0017] The square brackets in equation (5) indicate rounding down, that is, discarding the decimal and keeping the integer.

[0018] An output distribution matrix circuit with n row lines and n column lines, where none of these n row lines and column lines are occupied, is called an n-order output distribution matrix. For example... Figure 1 The output distribution matrix circuit has n row lines, namely r1, r2, ..., r k ,…r n The output distribution matrix circuit has n column lines, namely c1, c2, ..., c k ,…c n The kth line r k and the kth column line c k This is called having the same number, meaning the row and column lines have the same number.

[0019] n-order output distribution matrix circuits all have the following characteristics: only half of the matrix is ​​used; electrical switches are placed on the diagonals of the matrix; the power level of the matrix row lines is P; the power level of the k-th column line of the matrix is ​​P. R,k =x k,maxP; The number of electrical switches on the k-th column line is x. k,max On some lines, there is more than one way to place the electrical switches.

[0020] The algorithm flow for the output allocation matrix circuit scheduling strategy is as follows:

[0021] Step 1: Assume that the output distribution matrix circuit is of order n at this time. Calculate the appropriate charging power aP based on the user's allowed charging time, where a is a positive integer, P is the rated power of the modular converter, and a≤n.

[0022] Step 2: Calculate the power level P of each column line of the nth-order output distribution matrix circuit. R,k =x k,max P, find the one that satisfies P R,k The column line with the lowest power rating of ≥aP is the optimal charging output port at this time;

[0023] Step 3: All a row lines connected to the selected output port are occupied, and a column lines with the same number as these a row lines are occupied or disabled. At this time, the n-order output distribution matrix circuit is reduced to an (na)-order output distribution matrix circuit.

[0024] Step 4: After the current user finishes using the resource, release the occupied resource. The output allocation matrix circuit changes from (na) order back to n order. If another user comes to use the resource, simply execute the scheduling strategy again from step 1. If the current user has not finished using the resource and another user comes to use the resource, simply execute the scheduling strategy again from step 1. However, at this time, the output allocation matrix circuit has changed from n order to (na) order. You can treat the output allocation matrix circuit as (na) order.

[0025] In step two of the above algorithm, if the order of the output allocation matrix circuit changes, x needs to be recalculated. k,max It is determined according to formula (5):

[0026] (5)

[0027] It should be noted that n in equation (5) is the current value of the order of the output distribution matrix circuit, and k in equation (5) is the number of each column line when the order of the output distribution matrix circuit takes the current value, k=1,2,…,n.

[0028] The above scheduling strategy can further maximize the efficiency of the reconfigurable charging pile's multi-mode output circuit.

[0029] Compared with the prior art, the beneficial effects of the present invention are as follows: The reconfigurable charging pile multi-mode output circuit proposed in the present invention can realize arbitrary power output from 1P to nP, and the number of output channels can be 1 to n. It solves the contradiction between the single output mode of the existing charging pile and the diversified needs of users, and will not cause idle waste of equipment. Moreover, the wiring and electrical switches (relays or other forms of electrical switches) used are the most economical. Attached Figure Description

[0030] Figure 1 This is a simplified schematic diagram of the multi-mode output circuit for a reconfigurable charging pile.

[0031] Figure 2 This is a structural diagram of an output distribution matrix circuit when n=4.

[0032] Figure 3 A simplified schematic diagram of the reconfigurable charging pile multi-mode output circuit when n=4. Detailed Implementation

[0033] The present invention will now be described in further detail with reference to specific embodiments and accompanying drawings.

[0034] Example 1:

[0035] When n=4, according to the above optimization design method, x can be calculated. 1,max x 2,max x 3,max and x 4,max The designed 4th order output distribution matrix circuit has the following parameters: 4, 2, 1, and 1 respectively. Figure 2 As shown in the diagram. At this point, the simplified schematic of the reconfigurable charging pile output distribution circuit is as follows: Figure 3 As shown.

[0036] The following scheduling strategy algorithm is adopted:

[0037] Step 1: Assume that the output distribution matrix circuit is of order n at this time. Calculate the appropriate charging power aP based on the user's allowed charging time, where a is a positive integer, P is the rated power of the modular converter, and a≤n.

[0038] Step 2: Calculate the power level P of each column line of the nth-order output distribution matrix circuit. R,k =x k,max P, find the one that satisfies P R,k The column line with the lowest power rating of ≥aP is the optimal charging output port at this time;

[0039] Step 3: All a row lines connected to the selected output port are occupied, and a column lines with the same number as these a row lines are occupied or disabled. At this time, the n-order output distribution matrix circuit is reduced to an (na)-order output distribution matrix circuit.

[0040] Step 4: After the current user finishes using the resource, release the occupied resource. The output allocation matrix circuit changes from (na) order back to n order. If another user comes to use the resource, simply execute the scheduling strategy again from step 1. If the current user has not finished using the resource and another user comes to use the resource, simply execute the scheduling strategy again from step 1. However, at this time, the output allocation matrix circuit has changed from n order to (na) order. You can treat the output allocation matrix circuit as (na) order.

[0041] In step two of the above algorithm, if the order of the output allocation matrix circuit changes, x needs to be recalculated. k,max It is determined according to formula (5):

[0042] (5)

[0043] It should be noted that n in equation (5) is the current value of the order of the output distribution matrix circuit, and k in equation (5) is the number of each column line when the order of the output distribution matrix circuit takes the current value, k=1,2,…,n.

[0044] The present invention can be implemented in many different ways, and it is impossible to list them all here. The scope of protection of the present invention is determined by the independent claims in the claims, and the specific embodiments described herein should not be construed as limiting the scope of protection.

Claims

1. A reconfigurable charging pile multi-mode output circuit, characterized in that: The reconfigurable charging pile multi-mode output circuit proposed in this invention includes n modular converters with a rated power of P and an output distribution matrix circuit; the inputs of these n modular converters are connected to the input power supply of the charging pile, and the voltage of the input power supply of the charging pile is represented by u. d This indicates that n is a positive integer; the outputs of these n modular converters have a total of n paths, which are respectively connected to the n inputs of the output distribution matrix circuit, i.e., the row lines of the matrix circuit; The output distribution matrix circuit also has n outputs, which are the column lines of the matrix circuit, and are connected to the n load output ports of the charging pile respectively. Each row line and each column line of the matrix circuit represents a set of power lines. A set of power lines usually consists of two power lines, one positive and one negative. There is no electrical connection at the intersection of the row lines and column lines. The row lines and column lines need to be electrically connected or disconnected by an electrical switch. An n-order output distribution matrix circuit has the following characteristics: only half of the matrix is ​​used; electrical switches are installed on the diagonals of the matrix; the power level of all row lines is P; the power level of the k-th column line is P. R,k =x k,max P, with subscript k = 1, 2, ..., n; the number of electrical switches on the k-th column is x. k,max ; x k,max Determine using the following method: （1） The square brackets in equation (1) indicate rounding down, that is, discarding the decimal and keeping the integer.

2. The reconfigurable charging pile multi-mode output circuit according to claim 1, characterized in that: The reconfigurable charging pile multi-mode output circuit proposed in this invention adopts the following scheduling strategy: Step 1: Assume that the output distribution matrix circuit is of order n at this time. Calculate the appropriate charging power aP based on the user's allowed charging time, where a is a positive integer, P is the rated power of the modular converter, and a≤n. Step 2: Calculate the power level P of each column line of the nth-order output distribution matrix circuit. R,k =x k,max P, find the one that satisfies P R,k The column line with the lowest power rating of ≥aP is the optimal charging output port at this time; Step 3: All a row lines connected to the selected output port are occupied, and a column lines with the same number as these a row lines are occupied or disabled. At this time, the n-order output distribution matrix circuit is reduced to an (na)-order output distribution matrix circuit. Step 4: After the current user finishes using the resource, release the occupied resource. The output allocation matrix circuit changes from (na) order back to n order. If another user comes to use the resource, simply execute the scheduling strategy again from step 1. If the current user has not finished using the resource and another user comes to use the resource, simply execute the scheduling strategy again from step 1. However, at this time, the output allocation matrix circuit has changed from n order to (na) order. You can treat the output allocation matrix circuit as (na) order.

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