Energy storage cross-transformer anti-countercurrent control method

Abstract

The invention discloses an energy storage cross-transformer countercurrent prevention control method. The method comprises the following steps: S1, when the high-voltage incoming line power is too low or the total power of a transformer is less than or equal to 0; s2, judging whether the energy storage EMS is in a strategy mode or a manual discharge mode, if so, then performing the next step, and if not, stopping; s3, judging that the power of the energy storage pcs is greater than 0, if so, executing the next step, and if not, stopping; s4, the system sends a message that the power is reduced to 0 to the energy storage EMS; s5, reading the power of the energy storage EMS to judge whether the operation is stopped or not; and S6, continuously monitoring the high-voltage incoming line power, and when the power is greater than a set value, sending a power rising message to the energy storage EMS. Quick response and judgment can be realized, and when the power is too low, discharge is stopped by timely response to prevent generated power from flowing back to a power grid; energy storage can be discharged under the condition that any position of a power utilization main body is powered, and discharging is stopped under the condition that no power is used.

Description

Technical Field

[0001] The present invention belongs to the technical field of electric energy storage, and in particular relates to a method for controlling reverse flow prevention across energy storage transformers. Background Art

[0002] The energy storage cross-transformer anti-backflow control technology is mainly used to solve the problem that the energy storage power cannot be fully consumed in the transformer to which it belongs, and the power that cannot be consumed by the transformer is released to other transformers of the enterprise for consumption. During the cross-transformer transmission process, it must be ensured that the released power can be consumed internally by the enterprise and cannot be sent back to the power grid. At this time, a set of devices needs to be installed to achieve the effect of preventing backflow of high-voltage incoming lines.

[0003] At present, energy storage is mainly installed under the transformer for low-price charging and high-price discharge. During the discharge of energy storage, electricity cannot be sent back to the power grid and measures will be taken to prevent reverse flow. The energy storage cross-transformer anti-reverse flow control technology is based on the original control of transformer reverse flow. It can charge the energy storage in the transformer that is not using electricity, and then discharge the electricity to the transformer that is using electricity.

[0004] Ordinary anti-backflow technology can control the energy storage within its own transformer to be sufficient, ensuring that the stored energy cannot be discharged when the user does not need electricity, but it cannot transmit the electricity that cannot be used by its own transformer to other transformers for consumption.

[0005] The existing anti-backflow technology is that when the energy storage installation transformer is not using electricity, the energy storage stops discharging. However, there is a problem: if the enterprise's electricity is used by other transformers and its own transformer is not using electricity, the energy storage electricity cannot be used for consumption by other transformers.

[0006] Energy storage is now installed in various load-producing enterprises. The main purpose is to reduce peak loads and fill valleys. When the energy storage is discharged, it is necessary to ensure that the enterprise is still using electricity. If the enterprise is already resting at this time, then the energy storage discharge is meaningless. Therefore, the anti-reverse flow technology is to prevent this. The energy storage will not be discharged when the enterprise is not using electricity. The power bureau will follow a total incoming line table where the enterprise uses electricity. There are several transformers below, and each transformer carries a part of the load.

[0007] Generally speaking, when energy storage is installed, it is installed under a transformer, and each manufacturer will monitor the data of the transformer. If the transformer does not need to store energy, it will not discharge. However, if a transformer only carries part of the load, other transformers may still be using electricity. Summary of the invention

[0008] The purpose of the present invention is to overcome the shortcomings of the prior art and propose a method for controlling the backflow prevention of energy storage across transformers, which can achieve rapid response and judgment, and stop discharging in time when the power is too low, so as to prevent the power generation from flowing back to the power grid; and can discharge the energy storage when there is power at any position of the power user, and stop discharging when there is no power.

[0009] The technical solution of the present invention to solve the above technical problems is as follows:

[0010] A method for controlling reverse flow prevention of energy storage across transformers, the steps are as follows:

[0011] S1 When the high voltage incoming power is too low or the total transformer power is ≤0;

[0012] S2 determines whether the energy storage EMS is in strategy mode or manual discharge mode. If yes, proceed to the next step, otherwise, stop. S3 determines whether the energy storage pcs power is greater than 0. If yes, proceed to the next step, otherwise, stop.

[0013] The S4 system sends a message to the energy storage EMS that the power is reduced to 0;

[0014] S5 reads the energy storage EMS power to determine whether it has stopped running;

[0015] S6 continues to monitor the high-voltage incoming line power, and when the power is greater than a set value, it sends a power increase message to the energy storage EMS.

[0016] Preferably, step S1 specifically refers to monitoring the overall data of the high-voltage incoming line total meter. When it is found that the forward active power of the high-voltage incoming line total meter is always 0, or starts to go into reverse active power, it means that the enterprise as a whole has no electricity consumption, and at this time the energy storage is controlled to stop discharging.

[0017] Preferably, the high-voltage incoming line total meter refers to the enterprise's total incoming line meter, which does not have real-time power. Forward active power or reverse active power refers to simulating the real-time power of each minute through the electricity and time of the meter.

[0018] Preferably, the step S4 specifically refers to that step S2 and step S3 determine that the energy storage is still discharging, and then the system sends a message to the energy storage to command the energy storage EMS to reduce the energy storage pcs power to 0.

[0019] Preferably, the step S5 specifically refers to reading the data once after the step S4 is sent to determine whether the energy storage power has dropped to 0; if it has not dropped to 0, sending it again and issuing an alarm.

[0020] Preferably, step S6 specifically refers to continuing to monitor the main incoming line meter and when it is found that the power is greater than 0, slowly increasing the energy storage power, and judging in real time whether this power will cause reverse power supply. If not, continue to increase the power until it runs at maximum power.

[0021] Preferably, the energy storage EMS refers to the computing center of energy storage, which is responsible for receiving information and processing information; the energy storage pcs refers to the energy storage power conversion device, and the strategy mode of the energy storage EMS is to specify a charging and discharging time and continue to run in this mode; the manual discharge mode of the energy storage EMS refers to the manual control of energy storage discharge.

[0022] Preferably, the judgment device adopts a local gateway device, and all data are connected to the gateway on site, so as to quickly discover the negative power of the high-voltage power line, thereby quickly stopping the energy storage discharge and preventing the energy storage from flowing back into the power grid.

[0023] The present invention monitors the overall data of the high-voltage incoming line total meter. When it is found that the total forward active power of the high-voltage incoming line total meter is 0, or starts to go to the total reverse active power, it means that the enterprise as a whole has no electricity. At this time, controlling the energy storage to stop discharging can achieve rapid response and judgment. When the power is too low, the discharge is stopped in time to prevent the power generation from flowing back to the power grid. The energy storage can be discharged when there is electricity at any position of the electricity user, and stop discharging when there is no electricity. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the process of the present invention. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical effect and technical solution of the embodiment of the present invention clearer, the technical solution in the embodiment of the present invention is clearly and completely described below in conjunction with the drawings in the embodiment of the present invention; it is obvious that the described embodiment is a part of the embodiment of the present invention. Based on the embodiment disclosed in the present invention, other embodiments obtained by ordinary technicians in this field without making creative work should all fall within the scope of protection of the present invention.

[0026] Example 1

[0027] like Figure 1As shown in the figure, a method for controlling reverse flow across transformers for energy storage is used to collect data from the enterprise's main incoming line meter. The meter does not have real-time power. The real-time power of each minute is simulated through the power and time of the meter. When the power is found to be ≤0, it indicates that the enterprise is no longer using electricity or has already reversely transmitted electricity from photovoltaic power. At this time, we will initiate a judgment process. First, determine whether the energy storage EMS is in strategy mode or manual discharge mode, because both modes will cause discharge reverse flow. If yes, proceed to the next step (if not, the energy storage will not terminate the discharge). The next step is to determine whether the energy storage pcs is greater than 0. If it is greater than 0, it means that it is discharging. If yes, proceed to the next step (if not, the energy storage will not terminate the discharge). These two steps determine that the energy storage is still discharging, and the platform sends a message to the energy storage to command the EMS to reduce the pcs power to 0. After sending, read the data once to determine that the energy storage power has dropped to 0. If it has not dropped to 0, send it again and issue an alarm. Then continue to monitor the total incoming line meter. When the power is found to be greater than 0, slowly increase the energy storage power and judge in real time whether this power will cause reverse power transmission. If not, continue to increase the power until the maximum power is running.

[0028] Example 2

[0029] The judgment device of the present invention adopts a local gateway device, and all data are connected to the gateway on site, so that the negative power of the high-voltage power line can be quickly discovered, thereby quickly stopping the energy storage discharge and preventing the energy storage from flowing back into the power grid.

Claims

1. A method for preventing reverse flow across a transformer for energy storage, characterized in that: Here are the steps: S1 When the high voltage incoming power is too low or the total transformer power is ≤0; S2 determines whether the energy storage EMS is in strategy mode or manual discharge mode. If yes, proceed to the next step, otherwise, stop. S3 determines whether the energy storage pcs power is greater than 0. If yes, proceed to the next step, otherwise, stop. The S4 system sends a message to the energy storage EMS that the power is reduced to 0; S5 reads the energy storage EMS power to determine whether it has stopped running; S6 continues to monitor the high-voltage incoming line power, and when the power is greater than a set value, it sends a power increase message to the energy storage EMS.

2. A method for controlling reverse flow prevention of energy storage across transformers according to claim 1, characterized in that: The step S1 specifically refers to monitoring the overall data of the high-voltage incoming line meter. When it is found that the forward active power of the high-voltage incoming line meter is always 0, or starts to go to reverse active power, it means that the enterprise as a whole has no electricity consumption. At this time, the energy storage is controlled to stop discharging.

3. A method for controlling reverse flow prevention of energy storage across transformers as claimed in claim 2, characterized in that: The high-voltage incoming line total meter refers to the enterprise's total incoming line meter, which does not have real-time power. Forward active power or reverse active power refers to simulating the real-time power of each minute through the electricity and time of the meter.

4. A method for controlling reverse flow prevention of energy storage across transformers according to claim 1, characterized in that: The step S4 specifically means that if step S2 and step S3 determine that the energy storage is still discharging, the system sends a message to the energy storage to command the energy storage EMS to reduce the energy storage pcs power to 0.

5. The energy storage transformer reverse current prevention control method according to claim 1, characterized in that: The step S5 specifically refers to reading the data once after the step S4 is sent to determine whether the energy storage power has dropped to 0; if it has not dropped to 0, sending it again and issuing an alarm.

6. A method for controlling reverse flow prevention of energy storage across transformers according to claim 1, characterized in that: The step S6 specifically refers to continuing to monitor the total incoming line meter. When it is found that the power is greater than 0, the energy storage power is slowly increased, and it is determined in real time whether this power will cause reverse power supply. If not, the power is continuously increased until it runs at maximum power.

7. A method for controlling reverse flow prevention of energy storage across transformers according to claim 1, characterized in that: The energy storage EMS refers to the energy storage computing center, which is responsible for receiving information and processing information; the energy storage pcs refers to the energy storage power conversion device. The strategy mode of the energy storage EMS is to specify a charging and discharging time and continue to run in this mode; the manual discharge mode of the energy storage EMS refers to manual control of energy storage discharge.

8. The energy storage transformer reverse current prevention control method according to claim 1, characterized in that: The judgment device uses a local gateway device, and all data on site are connected to the gateway, so as to quickly detect the negative power of the high-voltage power line, thereby quickly stopping the energy storage discharge and preventing the energy storage from flowing back into the power grid.

Images