Dual power network power transmission method and dual power network power transmission system

Abstract

The present invention relates to a method for transmitting electric energy in a dual power supply network, comprising: when the load power is greater than the starting power of the generator power supply and less than or equal to the overload power of the generator power supply, if the actual output power of the previous energy storage device is equal to the maximum output power of the energy storage device and the actual output power of the generator power supply is the difference between the load power and the maximum output power of the energy storage device, then the actual output power of the energy storage device this time is equal to the difference between the load power and the decreasing transition power of the generator power supply, and the actual output power of the generator power supply is the decreasing transition power of the generator power supply; on the contrary, the actual output power PE of the energy storage device this time is equal to the difference between the load power and the increasing transition power of the generator power supply, and the actual output power of the generator power supply is the increasing transition power of the generator power supply. The beneficial effect is that two transition modes are added to improve the quality of electric energy provided to the load in the dual power supply network.

Description

Technical Field

[0001] The present invention belongs to the technical field of power supply, and in particular relates to a method for transmitting electric energy through a dual power supply network and a system for transmitting electric energy through a dual power supply network. Background Art

[0002] In many electricity consumption scenarios where the city grid cannot be used for power supply, it is necessary to use energy storage devices and generators to transmit electricity to the loads separately or simultaneously through the busbar, forming a switchable dual power supply network. Considering that the electricity cost of the generator is higher than that of the energy storage device, the relevant technology has designed a power output strategy for the switchable dual power supply network that gives priority to power supply by the energy storage device; considering that the motor needs to be prevented from idling after the generator is started, the relevant technology has designed a power output strategy for the switchable dual power supply network that gives priority to preventing the motor from idling. In addition, considering the overload power of the generator, when the relevant technology designs a power output strategy for the switchable dual power supply network, the switching mode will be set according to the overload power and starting power. In summary, the prior art has at least the following technical problems: first, there is no switchable dual power supply network that comprehensively considers the aforementioned output strategy; second, the prior art designs the overload power to be less than or equal to 0.5 times the starting power. If the difference range between the overload power and the starting power is increased (for example, the overload power is increased and the starting power is reduced), when the generator switches from high output power to low output power, or from low output power to high output power, the power fluctuation of the generator is often too large, thereby affecting the quality of the power provided to the load. Summary of the invention

[0003] The invention purpose of the technical solution of the present invention includes but is not limited to solving the above-mentioned technical problems. At least one aspect of the technical solution relates to providing a method for transmitting electric energy through a dual power supply network, wherein the dual power supply network includes an energy storage device and a generator, and the method for transmitting electric energy through a dual power supply network includes:

[0004] When the load power is greater than the starting power of the generator power supply and the load power is less than or equal to the overload power of the generator power supply, if the previous actual output power of the energy storage device is equal to the maximum output power of the energy storage device and the actual output power of the generator power supply is the difference between the load power and the maximum output power of the energy storage device, then the actual output power of the energy storage device this time is equal to the difference between the load power and the decreasing transition power of the generator power supply, and the actual output power of the generator power supply is the decreasing transition power of the generator power supply;

[0005] When the load power is greater than the overload power of the generator power supply, and the sum of the load power and the starting power of the generator power supply is greater than the sum of the overload power of the generator power supply and the maximum output power of the energy storage device, if the actual output power of the energy storage device last time is equal to the starting power of the generator power supply and the actual output power of the generator power supply is the difference between the load power and the starting power of the generator power supply, then the actual output power of the energy storage device this time is equal to the difference between the load power and the incremental transition power of the generator power supply, and the actual output power PG of the generator power supply is the incremental transition power of the generator power supply.

[0006] The technical solution of at least one aspect relates to a dual power supply network power transmission system, the system comprising at least one processor; and a memory storing instructions, which, when executed by at least one processor, implement the steps of the method described in switching the dual power supply network involved in the technical solution of at least one aspect of the present invention.

[0007] The beneficial effect of the present invention is that at least one technical solution of the present invention will not affect the quality of electric energy provided to the load due to excessive power fluctuation of the generator when the generator switches from high output power to low output power or from low output power to high output power. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 A topological diagram of a dual power supply network including a dual power supply network power transmission system;

[0009] Figure 2 It is a schematic diagram of the decreasing transition power priority switching mode;

[0010] Figure 3 It is a schematic diagram of the incremental transition power priority switching mode;

[0011] Figure 4 Schematic diagram of other switching modes;

[0012] Figure 5 Schematic diagram of a system for delivering electrical energy to a dual power supply network. DETAILED DESCRIPTION

[0013] The following examples further illustrate the content of the present invention, but should not be construed as limiting the present invention. Without departing from the spirit and substance of the present invention, modifications or substitutions made to the methods, steps or conditions of the present invention all fall within the scope of the present invention.

[0014] In many electricity consumption scenarios where the city grid cannot be used for power supply, such as sudden power outages in the city grid, it is necessary to use energy storage devices and generators to transmit electricity to the loads through the busbar alone or simultaneously, forming a switchable dual power supply network. Considering that the electricity cost (fuel cost) of the generator is higher than that of the energy storage device, the relevant technology has designed a power output strategy for the switchable dual power supply network that gives priority to power supply by the energy storage device; considering that the motor needs to be prevented from idling after the generator is started (for example, when the system determines based on the cost priority strategy that the energy storage device alone can output electricity to meet the load demand, the generator is ordered to stop outputting electricity, resulting in the generator idling), the relevant technology has designed a power output strategy for the switchable dual power supply network that gives priority to preventing the motor from idling. In addition, considering the overload power of the generator, when the relevant technology designs a power output strategy for the switchable dual power supply network, the switching mode will be set according to the overload power and starting power. In summary, the prior art has at least the following technical problems: first, there is no switchable dual power supply network that comprehensively considers the aforementioned output strategy; second, the prior art designs the overload power to be less than or equal to 0.5 times the starting power. If the difference range between the overload power and the starting power is increased (for example, the overload power is increased and the starting power is reduced), when the generator switches from high output power to low output power, or from low output power to high output power, the power fluctuation of the generator is often too large, thereby affecting the quality of the power provided to the load.

[0015] The schematic dual power supply network of the embodiment of the present invention can be referred to Figure 1 As shown, the dual power network transmission power system controls the energy storage device and the generator to provide power for the load, wherein the energy storage device includes a battery pack and a controller (not shown in the figure), and the module setting of the controller of the present invention is not specifically limited. For example, the controller may include an acquisition module, a processing module, and a power output module. The acquisition module is used to collect the generator power supply starting power P1, the generator power supply overload power P2, the generator power supply idling prevention power P3, and the load power P0 of the generator, and the maximum output power P4 of the energy storage device of the battery pack of the energy storage device. The processing module is used to compare and analyze the size of P0, P1, P2, P3, and P4 and output the processing results; the power output module adjusts the output of P1, P2, P3, and P4 of the battery pack and the generator according to the processing results. The above acquisition module, processing module, and power output module can be adjusted or combined according to the embodiments below.

[0016] The meanings of the symbols of the dual power network transmission power system are as follows:

[0017] PE represents the actual output power of the energy storage device;

[0018] PG represents the actual output power of the generator power supply;

[0019] P represents the sum of the actual output power PE of the energy storage device and the actual output power PG of the generator power supply;

[0020] P0 represents load power (actual detection power measured by load);

[0021] P1 represents the starting power of the generator power supply;

[0022] P2 represents the overload power of the generator power supply;

[0023] P3 represents the anti-idling power of the generator power supply, P3=P2-P1, P3≤P1;

[0024] P4 represents the maximum output power of the energy storage device;

[0025] P5 represents the decreasing transition power of the generator power supply;

[0026] P6 represents the incremental transition power of the generator power supply.

[0027] Some embodiments of the present invention relate to a method for transmitting electric energy through a dual power supply network, wherein the dual power supply network includes an energy storage device and a generator, and the method for transmitting electric energy through a dual power supply network includes:

[0028] When the load power P0 is greater than the starting power P1 of the generator power supply, and the load power P0 is less than or equal to the overload power P2 of the generator power supply, if the previous actual output power PE of the energy storage device is equal to the maximum output power P4 of the energy storage device and the actual output power PG of the generator power supply is the difference between the load power P0 and the maximum output power P4 of the energy storage device, then the actual output power PE of the energy storage device this time is equal to the difference between the load power P0 and the decreasing transition power P5 of the generator power supply, and the actual output power PG of the generator power supply is the decreasing transition power P5 of the generator power supply;

[0029] When the load power P0 is greater than the overload power P2 of the generator power supply, and the sum of the load power P0 and the starting power P1 of the generator power supply is greater than the sum of the overload power P2 of the generator power supply and the maximum output power P4 of the energy storage device, if the previous actual output power PE of the energy storage device is equal to the starting power P1 of the generator power supply and the actual output power PG of the generator power supply is the difference between the load power P0 and the starting power P1 of the generator power supply, then the actual output power PE of the energy storage device this time is equal to the difference between the load power P0 and the incremental transition power P6 of the generator power supply, and the actual output power PG of the generator power supply is the incremental transition power P6 of the generator power supply.

[0030] In the dual power network power transmission method of these embodiments of the present invention, a transition power priority switching mode can be added when switching from the dual output cost priority mode to the dual output balance priority mode, or when switching from the dual output balance priority mode to the dual output cost priority mode. The transition power priority switching mode can prevent the transition fluctuation of the actual output power of the generator power supply, wherein the decreasing transition power and the increasing transition power can be two or more point values ​​between the actual output power of the generator power supply of two adjacent modes (preferably increasing or decreasing in proportion), and the value can be automatically generated by the system. However, although the subsequent embodiments of the present invention describe a variety of methods based on automatic generation by the system, preset values ​​based on expert experience and the like are also within the selection range of the present invention.

[0031] A method for transmitting electric energy through a dual power supply network based on some of the aforementioned embodiments,

[0032] The decreasing transition power P5 of the generator power supply is decreased from the previous actual output power PG of the generator power supply to the difference between the load power P0 and the starting power P1 of the generator power supply;

[0033] The incremental transition power P6 of the generator power supply increases from the previous starting power P1 of the generator power supply to the overload power P2 of the generator power supply.

[0034] In the dual power network power transmission method of these embodiments of the present invention, the decreasing transition power P5 of the generator power supply and the increasing transition power P6 of the generator power supply are calculated by the system based on the previous actual output power PG of the generator power supply, the load power P0, and the starting power P1 of the generator power supply. Therefore, this implementation method sets two or more point values ​​between the previous actual output power PG of the generator power supply (the maximum is the overload power P2 of the generator power supply) and the difference between the load power P0 and the starting power P1 of the generator power supply to prevent transitional fluctuations in the actual output power of the generator power supply.

[0035] refer to Figure 2 As shown, in the dual power network power transmission method based on some of the aforementioned embodiments, the decreasing transition power P5 of the generator power source decreases from 0.5 times the actual output power PG of the generator power source to the difference between the load power P0 and the starting power P1 of the generator power source;

[0036] refer to Figure 3 As shown, the incremental transition power P6 of the generator power supply increases from twice the actual output power PG of the generator power supply to the overload power P2 of the generator power supply.

[0037] In the dual power supply network power transmission method of these embodiments of the present invention, considering that when the difference between the previous (the last mode before the transition power priority switching mode) actual output power PG of the generator power supply and the next (the next mode after the transition power priority switching mode) actual output power PG of the generator power supply is too large, the actual output power of the generator power supply may still fluctuate excessively, the decreasing transition power P5 of the generator power supply is changed to 0.5 times the actual output power PG of the generator power supply, and the increasing transition power P6 of the generator power supply is changed to 2 times the actual output power PG of the generator power supply, thereby avoiding the actual output power of the generator power supply from fluctuating excessively due to the excessive difference, and still providing a higher power quality for the load.

[0038] In the dual power network power transmission method based on some of the aforementioned embodiments, the decreasing transition power P5 of the generator power source decreases linearly; and the increasing transition power P6 of the generator power source increases linearly.

[0039] In the dual power supply network power transmission method of these embodiments of the present invention, in order to further improve the power quality provided to the load, the decreasing transition power and the increasing transition power are multiple proportional increase or decrease values ​​between the actual output power of the generator power supplies of two adjacent modes, and linear increase or decrease is adopted.

[0040] In the dual power supply network power transmission method based on some of the aforementioned embodiments, the overload power P2 of the generator power supply is less than or equal to 2 to 4 times the starting power P1 of the generator power supply; a further optional embodiment is that the overload power P2 of the generator power supply is less than or equal to 2 to 3 times the starting power P1 of the generator power supply.

[0041] In the dual power network power transmission method of these embodiments of the present invention, the overload power P2 of the generator power supply can be increased to an extreme value of 3 times or 4 times the starting power P1 of the generator power supply, which exceeds the limitation of the overload power P2 of the motor power supply in the related art that is less than or equal to 2 times the starting power P1 of the generator power supply. At the same time, due to the transition power priority switching mode, it is ensured that the overload power P2 of the generator power supply can be increased to an extreme value of 3 times or 4 times the starting power P1 of the generator power supply, which avoids the excessive difference between the actual output power of the generator power supply before and after and causes the actual output power of the generator power supply to fluctuate transiently, and can also provide a higher power quality for the load. Specifically, P1≤0.5P2 in the related art causes the overload power of the generator power supply to be close to the starting power of the generator power supply. If the power range is increased, when switching from high to low or from low to high, the power fluctuation of the generator is too large, which affects the power quality provided to the load and limits the application of the dual power network in certain scenarios with high power quality requirements.

[0042] The output power of the energy storage system increases linearly with the load power of the load circuit, but the resistance of the energy storage system continues to increase with the power growth, which will increase the power loss of the energy storage system itself.

[0043] The new switching mode included in the dual power network power transmission method of the following embodiment can be referred to Figure 4 , the transition power priority switching mode still refers to Figure 2 , Figure 3 .

[0044] The dual power network power transmission method based on some of the aforementioned embodiments further includes: when the load power P0 is less than or equal to the starting power P1 of the generator power supply, the actual output power PE of the energy storage device is equal to the load power P0, and the actual output power PG of the generator power supply is 0.

[0045] In the dual power network power transmission method of these embodiments of the present invention, a single output VSG (virtual synchronous generator) mode is also provided, that is, the power is completely output by the energy storage device with the virtual synchronous generator as the load.

[0046] The method for transmitting electric energy in a dual power supply network based on some of the aforementioned embodiments further includes: when the load power P0 is greater than the starting power P1 of the generator power supply, and the load power P0 is less than or equal to the overload power P2 of the generator power supply, the actual output power PE of the energy storage device is equal to the starting power P1 of the generator power supply, and the actual output power PG of the generator power supply is the difference between the load power P0 and the starting power P1 of the generator power supply.

[0047] In the dual power network power transmission method of these embodiments of the present invention, a dual output balancing priority mode is also provided, in which PE is preferentially supplemented by P1 output PG, thereby balancing the generator power supply and the energy storage device.

[0048] In the dual power network power transmission method of these embodiments of the present invention, the dual power network power transmission method also includes: when the load power P0 is greater than the overload power P2 of the generator power supply, and the sum of the load power P0 and the starting power P1 of the generator power supply is less than or equal to the sum of the overload power P2 of the generator power supply and the maximum output power P4 of the energy storage device, the actual output power PE of the energy storage device is equal to the difference between the load power P0 and the anti-idling power P3 of the generator power supply, and the actual output power PG of the generator power supply is the anti-idling power P3 of the generator power supply.

[0049] In the dual power network power transmission method of these embodiments of the present invention, a dual output anti-idling priority mode is also provided, in which PG prioritizes to output PE with P3 to prevent energy loss caused by generator idling.

[0050] In the dual power network power transmission method of these embodiments of the present invention, the dual power network power transmission method also includes: when the load power P0 is greater than the overload power P2 of the generator power supply, and the sum of the load power P0 and the starting power P1 of the generator power supply is greater than the sum of the overload power P2 of the generator power supply and the maximum output power P4 of the energy storage device, the actual output power PE of the energy storage device is equal to the maximum output power P4 of the energy storage device, and the actual output power PG of the generator power supply is the difference between the load power P0 and the maximum output power P4 of the energy storage device.

[0051] In the dual power network power transmission method of these embodiments of the present invention, a dual output cost priority mode is also provided, in which PE prioritizes P4 output to supplement PG, thereby ensuring that the energy storage device outputs power as much as possible, and using the generator power supply with higher power cost as a supplementary output power.

[0052] The above embodiments are merely explanations of the technical solutions claimed to be protected by the present invention. The method for transmitting electric energy through a dual power supply network may also include, for example, an alarm mode, etc., which will not be elaborated herein.

[0053] refer to Figure 5 As shown, an exemplary dual power network power transmission system 1 of the present invention includes at least one processor 2; and a memory 3 and an interface 4, which store instructions. When the instructions are executed by at least one processor, the steps of the dual power network power transmission method according to an embodiment of the present invention are implemented.

[0054] Specific implementations of the subject matter have been described. Other implementations are within the scope of the following claims. For example, the activities recited in the claims can be performed in a different order and still achieve the desired results. As an example, the processes described in the accompanying drawings do not necessarily require the specific order or sequential order shown in order to achieve the desired results. In certain implementations, multitasking and parallel processing may be advantageous.

Claims

1. A method for transmitting electric energy in a dual power supply network, wherein the dual power supply network comprises an energy storage device and a generator, characterized in that: The dual power network power transmission method comprises: When the load power is greater than the starting power of the generator power supply and the load power is less than or equal to the overload power of the generator power supply, if the previous actual output power of the energy storage device is equal to the maximum output power of the energy storage device and the actual output power of the generator power supply is the difference between the load power and the maximum output power of the energy storage device, then the actual output power of the energy storage device this time is equal to the difference between the load power and the decreasing transition power of the generator power supply, and the actual output power of the generator power supply is the decreasing transition power of the generator power supply; When the load power is greater than the overload power of the generator power supply, and the sum of the load power and the starting power of the generator power supply is greater than the sum of the overload power of the generator power supply and the maximum output power of the energy storage device, if the previous actual output power of the energy storage device is equal to the starting power of the generator power supply and the actual output power of the generator power supply is the difference between the load power and the starting power of the generator power supply, then the actual output power of the energy storage device this time is equal to the difference between the load power and the incremental transition power of the generator power supply, and the actual output power of the generator power supply is the incremental transition power of the generator power supply; The decreasing transition power of the generator power supply decreases from the previous actual output power of the generator power supply to the difference between the load power and the starting power of the generator power supply; The incremental transition power of the generator power supply is increased from the previous starting power of the generator power supply to the overload power of the generator power supply.

2. A method for transmitting electric energy via a dual power supply network as claimed in claim 1, characterized in that: The decreasing transition power of the generator power supply decreases from 0.5 times the actual output power of the generator power supply to the difference between the load power and the starting power of the generator power supply; The incremental transition power of the generator power supply increases incrementally from twice the actual output power of the generator power supply to the overload power of the generator power supply.

3. A method for transmitting electric energy in a dual power supply network according to any one of claims 1 to 2, characterized in that: The decreasing transition power of the generator power supply decreases linearly; The incremental transition power of the generator power source increases linearly.

4. A method for transmitting electric energy in a dual power supply network according to any one of claims 1 to 2, characterized in that: The overload power of the generator power supply is less than or equal to 2 to 4 times the starting power of the generator power supply.

5. A method for transmitting electric energy via a dual power supply network as claimed in claim 4, characterized in that: The overload power of the generator power supply is less than or equal to 2 to 3 times the starting power of the generator power supply.

6. A method for transmitting electric energy in a dual power supply network according to any one of claims 1 to 2, characterized in that: The dual power network power transmission method also includes: When the load power is less than or equal to the starting power of the generator power supply, the actual output power of the energy storage device is equal to the load power, and the actual output power of the generator power supply is 0.

7. A method for transmitting electric energy in a dual power supply network according to any one of claims 1 to 2, characterized in that: The dual power network power transmission method also includes: When the load power is greater than the starting power of the generator power supply and the load power is less than or equal to the overload power of the generator power supply, the actual output power of the energy storage device is equal to the starting power of the generator power supply, and the actual output power of the generator power supply is the difference between the load power and the starting power of the generator power supply.

8. A method for transmitting electric energy in a dual power supply network as claimed in any one of claims 1 to 2, characterized in that: The dual power network power transmission method also includes: When the load power is greater than the overload power of the generator power supply, and the sum of the load power and the starting power of the generator power supply is less than or equal to the sum of the overload power of the generator power supply and the maximum output power of the energy storage device, the actual output power of the energy storage device is equal to the difference between the load power and the anti-idling power of the generator power supply, and the actual output power of the generator power supply is the anti-idling power of the generator power supply.

9. A method for transmitting electric energy in a dual power supply network according to any one of claims 1 to 2, characterized in that: The dual power network power transmission method also includes: When the load power is greater than the overload power of the generator power supply, and the sum of the load power and the starting power of the generator power supply is greater than the sum of the overload power of the generator power supply and the maximum output power of the energy storage device, the actual output power of the energy storage device is equal to the maximum output power of the energy storage device, and the actual output power of the generator power supply is the difference between the load power and the maximum output power of the energy storage device.

10. A dual power network power transmission system, characterized in that: The system comprises at least one processor; and a memory storing instructions, which, when executed by the at least one processor, implement the steps of the method according to any one of claims 1 to 9.

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