Centralized battery charging and replacing cabinet energy management system and method

Abstract

The invention discloses a centralized charging cabinet energy management system and method, and the system comprises a main control unit which is electrically connected with a centralized charging cabinet unit, an AC load unit, a DC load unit, a power grid, and a new energy power generation unit. The centralized battery charging and replacing cabinet unit is used for managing the charging process of a plurality of batteries in a centralized manner; the AC load unit is used for supplying power to AC equipment, and the DC load unit is used for supplying power to DC equipment. According to the invention, the problems of insufficient energy management, low charging efficiency and battery life decline in a traditional charging mode are solved, and through an intelligent charging strategy, dynamic power scheduling and battery health management, the system has significant advantages in the aspects of improving the charging efficiency, prolonging the service life of the battery and reducing the waste of electric power resources.

Description

Technical Field

[0001] The present invention relates to the field of electricity, and in particular to a centralized charging and swapping cabinet energy management system and method. Background Art

[0002] With the popularity of electric vehicles and electric bicycles, the construction of charging / battery swapping facilities has gradually become a key issue in the development of electric vehicles and electric bicycles. Most of the existing charging and battery swapping facilities use traditional charging piles or battery swapping cabinets to charge or replace batteries. The existing charging and battery swapping systems have many shortcomings in energy management, such as uneven energy distribution, low charging efficiency, and long charging time. Especially in the scenario of centralized charging in battery swapping cabinets, the optimal scheduling of energy is crucial. Summary of the invention

[0003] In order to solve the above technical problems, the present invention proposes a centralized charging and swapping cabinet energy management system.

[0004] The purpose of the present invention is achieved through the following technical solutions:

[0005] A centralized charging and swapping cabinet energy management system includes a main control unit, the main control unit is electrically connected to a centralized charging and swapping cabinet unit, an AC load unit, a DC load unit, a power grid and a new energy power generation unit; the centralized charging and swapping cabinet unit is used to centrally manage the charging process of multiple batteries; the AC load unit is used to power AC equipment, and the DC load unit is used to power DC equipment;

[0006] The main control unit realizes four states according to the status control of each unit:

[0007] Grid-connected state 1: The grid side supplies power to the battery, AC load unit and DC load unit managed by the centralized charging and swapping cabinet unit through the bidirectional AC / DC unit by rectification to provide energy; Grid-connected state 2: The new energy power generation unit feeds back to the grid through the bidirectional AC / DC unit inverter;

[0008] Off-grid state 1: Not connected to the grid, the battery exchange cabinet unit discharges in reverse to provide energy to the AC load unit and DC load unit;

[0009] Off-grid state 2: Not connected to the power grid, the new energy power generation unit operates in an isolated island, providing energy to the AC load unit, DC load unit and the battery managed by the centralized charging and swapping cabinet unit.

[0010] As a further improvement, the AC load unit includes an AC charging module, an AC motor and an AC lighting module.

[0011] As a further improvement, the DC load unit includes a DC charging module, a DC lighting module and a DC electric drive module.

[0012] As a further improvement, the new energy power generation unit includes a photovoltaic power generation module and a wind power generation module.

[0013] A centralized charging and swapping cabinet energy management method adopts the above-mentioned centralized charging and swapping cabinet energy management system, comprising the following steps:

[0014] Step 1: Set P nn (t) represents the total power of the new energy power generation unit connected to the battery swap cabinet in the centralized charging and swap cabinet unit; P load (t) represents the total power of the AC load unit and the DC load unit, P load max (t) represents the maximum load power, P cutload (t) represents the power after cutting off some unimportant loads; SOC(t) represents the total battery energy of the battery swap cabinet in the centralized charging and swap cabinet unit, P Bat (t) represents the total battery charging power of the battery swap cabinet in the centralized charging and swap cabinet unit; P g (t) represents the energy on the grid side, Represents the grid output energy, Indicates feeding energy into the grid;

[0015] SOC max (t) represents the maximum total battery energy of the battery swap cabinet in the centralized charging and swap cabinet unit;

[0016] Step 2: Determine whether the grid is connected, if yes, proceed to step 3, otherwise proceed to step 4;

[0017] Step 3: Determine whether P nn (t)>P load (t), if yes, go to step 3.1), otherwise go to step 3.2);

[0018] Step 3.1), determine whether SOC(t)<SOC max (t), if yes, go to step 3.1.1), otherwise go to step 3.1.2);

[0019] Step 3.1.1):

[0020] When the priority of grid-connected revenue energy allocation is set high, there are:

[0021]

[0022] When the charging energy allocation priority is set high, there are:

[0023]

[0024]

[0025] When the load energy distribution priority is set high, there are:

[0026]

[0027] Step 3.1.2)

[0028] If SOC(t) = SOC max (t)

[0029] When the priority of grid-connected revenue energy allocation is set high:

[0030] P g - (t) = P nn (t)-P cutload (t) (7)

[0031] When the load energy distribution priority is set high:

[0032] P g - (t) = P nn (t)-P load max (t) (8)

[0033] Step 3.2), determine whether SOC(t)<SOC max (t), if yes, go to step 3.2.1), otherwise go to step 3.2.2);

[0034] Step 3.2.1):

[0035] When the priority of grid-connected revenue energy allocation is set high:

[0036] P g - (t) = P nn (t)-P cutload (t) (9)

[0037] When the charging energy allocation priority is set to high:

[0038] P g + (t) = P load (t)+P Batmax -P nn (t) (10)

[0039] When the load energy distribution priority is set high:

[0040] P g + (t) = P load max (t)+P Bat -P nn (t) (11)

[0041] Step 3.2.2):

[0042] When the priority of grid-connected revenue energy allocation is set high:

[0043] P g - (t) = P nn (t)-P cutload (t) (12)

[0044] When the load energy distribution priority is set high:

[0045] P g + (t) = P load max (t)-P nn (t)-P Bat (t) (13)

[0046] Step 4: Determine whether P nn (t)>P load (t), if yes, go to step 4.1), otherwise go to step 4.2);

[0047] Step 4.1), determine whether SOC(t)<SOC max (t), if yes, go to step 4.1.1), otherwise go to step 4.1.2)

[0048] Step 4.1.1)

[0049] When the charging energy allocation priority is set to high:

[0050] P nn (t) = P cutload (t)+P Bat_max (t) (14)

[0051] When the load energy distribution priority is set high:

[0052] P nn (t) = P load_max (t)+P Bat (t) (15)

[0053] Step 4.1.2)

[0054] When SOC(t) = SOC max (t),

[0055] P nn (t) = P load (t) (16)

[0056] Step 4.2:

[0057] When the charging energy allocation priority is set to high:

[0058] P nn (t) = P Bat (t)(P nn (t)≤P Bat_max (t)) (17)

[0059] P nn (t) = P cutload (t)+P Bat (t)(P nn (t)>P Bat_max (t)) (18)

[0060] When the load energy distribution priority is set high:

[0061] P cutload (t) = P nn (t)+P Bat (t) (19).

[0062] Further improvement, assuming that the solution set for period T is

[0063]

[0064] in, The power of buying and selling electricity from the power grid during period t satisfies the power transaction constraints of steps 1 to 4;

[0065] is the load power that can be removed during period t, satisfying the load power allocation constraints of steps 1 to 4;

[0066] is the charging and discharging power of the energy storage battery in time period t, satisfying the constraints of charging power allocation in steps 1 to 4;

[0067] is the maximum output power of renewable energy power generation in time period t, which satisfies the constraints of maximum output power in steps 1 to 4; the optimal solution of energy allocation in time period T can be obtained:

[0068]

[0069] For the T period A collection of; For the T period A collection of; For the T period A collection of For the T period A set of; t is a continuous period of time within time T, t∈T.

[0070] The beneficial effects of the present invention are:

[0071] The present invention solves the problems of insufficient energy management, low charging efficiency and battery life decline in traditional charging methods. Through intelligent charging strategies, dynamic power scheduling and battery health management, the present invention has significant advantages in improving charging efficiency, effectively reducing the number of battery charge and discharge cycles, thereby extending battery life and reducing waste of power resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] The present invention is further described with reference to the accompanying drawings, but the contents in the accompanying drawings do not constitute any limitation to the present invention.

[0073] Figure 1 This is the topology diagram of the centralized charging and swapping cabinet system.

[0074] Figure 2 Flowchart of the energy allocation strategy.

[0075] Figure 3 This is the power distribution curve of the energy management strategy in actual application. DETAILED DESCRIPTION

[0076] In order to make the purpose, technical solutions and advantages of the invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and examples.

[0077] Example 1

[0078] Principle of energy management system for centralized charging and swapping cabinets

[0079] The centralized charging and swapping cabinet energy management system of the present invention is as follows Figure 1 As shown, it includes the following components:

[0080] (1) Centralized charging and swapping cabinet unit: used to centrally manage the charging process of multiple batteries and dynamically adjust the charging power and charging time of each battery; store electric vehicle / electric bicycle batteries and support rapid battery replacement and charging operations.

[0081] (2) Main control unit: responsible for overall energy scheduling and optimization, including data communication, power optimization, battery status monitoring, load balancing, system-level security protection, etc.

[0082] (3) AC load unit: It provides power for AC equipment, including AC charging, AC motors, AC lighting, etc.

[0083] (4) DC load unit: It provides power for DC devices, including DC charging, DC lighting, DC drive, etc.

[0084] The energy management system is designed to work in the following four modes:

[0085] (1) Grid-connected state 1 (grid-side power supply mode), the grid side provides energy to other power-consuming units in the system (load, electric vehicle charging, battery charging) through a bidirectional AC / DC unit and rectification method;

[0086] (2) Grid-connected state 2 (grid-connected feeding mode), the new energy access (photovoltaic, breeze) part in the power exchange cabinet unit feeds back to the grid through the bidirectional AC / DC unit inverter;

[0087] (3) Off-grid state 1 (battery exchange cabinet discharge mode), the battery exchange cabinet unit discharges in reverse to provide energy to other power-consuming units in the system.

[0088] (4) Off-grid state 2 (new energy island mode), the new energy (photovoltaic, breeze) in the power exchange cabinet unit is connected to the island to operate, providing energy to other power-consuming units in the system.

[0089] Energy Management System Strategies

[0090] P nn (t) Total power of new energy access (breeze power generation, photovoltaic power generation) in the power exchange cabinet unit; P load (t) represents the load (AC load, DC load) module power, P load max (t) is the maximum load power, P cutload (t) is the power after removing some unimportant loads; SOC(t) represents the total battery energy of the battery swap cabinet unit, P Bat (t) represents the total battery charging power of the battery swap cabinet unit; P g (t) represents the measured energy of the power grid (the output energy of the power grid is Used to feed energy to the grid ).

[0091] The real-time energy control strategy is as follows:

[0092] (1) In the grid-connected state:

[0093] a. When P nn (t)>P load (t), and SOC(t)<SOC max (t),

[0094] ①Grid-connected revenue energy allocation has high priority:

[0095]

[0096] ②Charging energy allocation has high priority:

[0097]

[0098] ③ Load energy allocation has high priority:

[0099]

[0100] b. When P nn (t)>P load (t), and SOC(t)=SOC max (t),

[0101] ①Grid-connected revenue energy allocation has high priority:

[0102] P g - (t) = P nn (t)-P cutload (t) (7)

[0103] ② Load energy allocation has high priority:

[0104] P g - (t) = P nn (t)-P load max (t) (8)

[0105] c. When P nn (t)≤P load (t), and SOC(t)<SOC max (t),

[0106] ①Grid-connected revenue energy allocation has high priority:

[0107] P g - (t) = P nn (t)-P cutload (t) (9)

[0108] ②Charging energy allocation has high priority:

[0109] P g + (t) = P load (t)+P Batmax -P nn (t) (10)

[0110] ③ Load energy allocation has high priority:

[0111] P g + (t) = P load max (t)+P Bat -P nn (t) (11)

[0112] d. When Pnn (t)≤P load (t), and SOC(t)=SOC max (t),

[0113] ①Grid-connected revenue energy allocation has high priority:

[0114] P g - (t) = P nn (t)-P cutload (t) (12)

[0115] ② Load energy allocation has high priority:

[0116] P g + (t) = P load max (t)-P nn (t)-P Bat (t) (13)

[0117] (2) Off-grid state:

[0118] e. When P nn (t)>P load (t), and SOC(t)<SOC max (t),

[0119] ①Charging energy allocation has high priority:

[0120] P nn (t) = P cutload (t)+P Bat_max (t) (14)

[0121] ② Load energy allocation has high priority:

[0122] P nn (t) = P load_max (t)+P Bat (t) (15)

[0123] f. When P nn (t)>P load (t), and SOC(t)=SOC max (t),

[0124] P nn (t) = P load (t) (16)

[0125] g. When P nn (t)≤P load (t), and SOC(t)≤SOC max (t), there are the following situations:

[0126] ①Charging energy allocation has high priority:

[0127] P nn (t) = P Bat (t)(P nn (t)≤P Bat_max (t)) (17)

[0128] P nn (t) = P cutload (t)+P Bat (t)(P nn (t)>P Bat_max (t)) (18)

[0129] ② Load energy allocation has high priority:

[0130] P cutload (t) = P nn (t)+P Bat (t) (19)

[0131] Through the above real-time power control, we can get the power solution of each unit in the T period. Assume that the solution set in the t period is:

[0132] in, The power of buying and selling electricity from the power grid during period t satisfies the power transaction constraints of steps 1 to 4;

[0133] is the load power that can be removed during period t, satisfying the load power allocation constraints of steps 1 to 4;

[0134] is the charging and discharging power of the energy storage battery in time period t, satisfying the constraints of charging power allocation in steps 1 to 4;

[0135] is the maximum output power of renewable energy power generation in time period t, which satisfies the constraints of maximum output power in steps 1 to 4; the optimal solution of energy allocation in time period T can be obtained:

[0136]

[0137] For the T period A collection of; For the T period A collection of; For the T period A collection of For the T period A set of; t is a continuous period of time within time T, t∈T.

[0138] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A centralized charging and swapping cabinet energy management system, characterized in that: It includes a main control unit, which is electrically connected to a centralized charging and swapping cabinet unit, an AC load unit, a DC load unit, a power grid and a new energy power generation unit; the centralized charging and swapping cabinet unit is used to centrally manage the charging process of multiple batteries; the AC load unit is used to power AC equipment, and the DC load unit is used to power DC equipment; The main control unit realizes four states according to the status control of each unit: Grid-connected state 1: The grid side supplies power to the battery, AC load unit and DC load unit managed by the centralized charging and swapping cabinet unit through the bidirectional AC / DC unit by rectification to provide energy; Grid-connected state 2: The new energy power generation unit feeds back to the grid through the bidirectional AC / DC unit inverter; Off-grid state 1: Not connected to the grid, the battery exchange cabinet unit discharges in reverse to provide energy to the AC load unit and DC load unit; Off-grid state 2: Not connected to the power grid, the new energy power generation unit operates in an isolated island, providing energy to the AC load unit, DC load unit and the battery managed by the centralized charging and swapping cabinet unit.

2. The centralized charging and swapping cabinet energy management system according to claim 1, characterized in that: The AC load unit includes an AC charging module, an AC motor and an AC lighting module.

3. The centralized charging and swapping cabinet energy management system according to claim 1, characterized in that: The DC load unit includes a DC charging module, a DC lighting module and a DC electric drive module.

4. The centralized charging and swapping cabinet energy management system according to claim 1, characterized in that: The new energy power generation unit includes a photovoltaic power generation module and a wind power generation module.

5. A centralized charging and swapping cabinet energy management method, characterized in that: The centralized charging and swapping cabinet energy management system according to any one of claims 1 to 4 comprises the following steps: Step 1: Set P nn (t) represents the total power of the new energy power generation unit connected to the battery swap cabinet in the centralized charging and swap cabinet unit; P load (t) represents the total power of the AC load unit and the DC load unit, P loadmax (t) represents the maximum load power, P cutload (t) represents the power after cutting off some unimportant loads; SOC(t) represents the total battery energy of the battery swap cabinet in the centralized charging and swap cabinet unit, P Bat (t) represents the total battery charging power of the battery swap cabinet in the centralized charging and swap cabinet unit; P g (t) represents the energy on the grid side, Represents the grid output energy, Indicates feeding energy into the grid; SOC max (t) represents the maximum total battery energy of the battery swap cabinet in the centralized charging and swap cabinet unit; Step 2: Determine whether the grid is connected, if yes, proceed to step 3, otherwise proceed to step 4; Step 3: Determine whether P nn (t)>P load (t), if yes, go to step 3.1), otherwise go to step 3.2); Step 3.1), determine whether SOC(t)<SOC max (t), if yes, go to step 3.1.1), otherwise go to step 3.1.2); Step 3.1.1): When the priority of grid-connected revenue energy allocation is set high, there are: When the charging energy allocation priority is set high, there are: When the load energy distribution priority is set high, there are: Step 3.1.2) If SOC(t) = SOC max (t) When the priority of grid-connected revenue energy allocation is set high: P g - (t)=P nn (t)-P cutload (t) (7) When the load energy distribution priority is set high: P g - (t)=P nn (t)-P loadmax (t) (8) Step 3.2), determine whether SOC(t)<SOC max (t), if yes, go to step 3.2.1), otherwise go to step 3.2.2); Step 3.2.1): When the priority of grid-connected revenue energy allocation is set high: P g - (t)=P nn (t)-P cutload (t) (9) When the charging energy allocation priority is set to high: P g + (t)=P load (t)+P Batmax -P nn (t) (10) When the load energy distribution priority is set high: P g + (t)=P loadmax (t)+P Bat -P nn (t) (11) Step 3.2.2): When the priority of grid-connected revenue energy allocation is set high: P g - (t)=P nn (t)-P cutload (t) (12) When the load energy distribution priority is set high: P g + (t)=P loadmax (t)-P nn (t)-P Bat (t) (13) Step 4: Determine whether P nn (t)>P load (t), if yes, go to step 4.1), otherwise go to step 4.2); Step 4.1), determine whether SOC(t)<SOC max (t), if yes, go to step 4.1.1), otherwise go to step 4.1.2) Step 4.1.1) When the charging energy allocation priority is set to high: P nn (t)=P cutload (t)+P Bat_max (t) (14) When the load energy distribution priority is set high: P nn (t)=P load_max (t)+P Bat (t) (15) Step 4.1.2) When SOC(t) = SOC max (t), P nn (t)=P load (t) (16) Step 4.2: When the charging energy allocation priority is set to high: P nn (t)=P Bat (t)(P nn (t)≤P Bat_max (t)) (17) P nn (t)=P cutload (t)+P Bat (t)(P nn (t)>P Bat_max (t)) (18) When the load energy distribution priority is set high: P cutload (t)=P nn (t)+P Bat (t) (19)。 6. The centralized charging and swapping cabinet energy management method according to claim 5, characterized in that: Assume that the solution set for period T is: in, The power of buying and selling electricity from the power grid during period t satisfies the power transaction constraints of steps 1 to 4; is the load power that can be removed during period t, satisfying the load power allocation constraints of steps 1 to 4; is the charging and discharging power of the energy storage battery in time period t, satisfying the constraints of charging power allocation in steps 1 to 4; is the maximum output power of renewable energy power generation in time period t, which satisfies the constraints of maximum output power in steps 1 to 4; the optimal solution of energy allocation in time period T can be obtained: For the T period A collection of; For the T period A collection of; For the T period A collection of For the T period A set of; t is a continuous period of time within time T, t∈T.

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