A method for determining charging piles to be put into operation according to transformer redundant capacity

Abstract

The application relates to the technical field of energy management, and particularly discloses a method for determining input charging piles according to transformer redundancy capacity, which comprises the following steps: setting a measurement and control box, a distribution box, a parking space and judging the input of the charging pile; detecting different redundancy capacities at different time periods in a day by using existing transformer capacity; inputting the charging pile with demand; relying on power carrier technology to communicate and connect three terminal devices, namely, an incoming line cabinet, a charging pile distribution box and a charging pile; and relying on a programmable controller to judge whether the transformer redundancy capacity allows the charging pile to be put into use, so that the problem that a power supply department is worried about whether the transformer is overloaded and damaged, thereby reducing the power supply reliability, is solved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of energy management, and particularly relates to a method for determining input of charging piles according to transformer redundant capacity. BACKGROUND

[0002] The charging pile refers to a charging device for providing energy supplement for electric vehicles, and has a function similar to a refueling machine in a gas station, can be fixed on the ground or a wall, is installed in a public building and a parking lot or a charging station of a residential area, and can charge various types of electric vehicles according to different voltage levels. The input end of the charging pile is directly connected with an alternating current power grid, and the output end is provided with a charging plug for charging electric vehicles.

[0003] The charging pile of a real estate residential area and a rural user is generally a slow charging pile, and the power is 3.5kW and 7kW. The transformer capacity of a power supply department is designed according to the peak value of the apparent power, and contains a certain redundant capacity, which is referred to as redundant capacity. Different redundant capacities are formed at different time periods every day, and the rated value is not allowed to be reached in actual operation, so as to prevent the transformer from being damaged due to overload.

[0004] When a resident applies to install a charging pile to the power supply department, the power supply department will determine whether to approve the user's application according to the redundant capacity of the highest peak value. Due to insufficient transformer redundant capacity, the power supply department either does not approve the application of installing a charging pile or allows the application only by replacing a larger transformer capacity. However, replacing a larger capacity transformer will cause greater investment due to various factors such as power distribution equipment. When the transformer redundant capacity is not determined, how to realize reasonable, economic and intelligent charging of electric vehicles without increasing the capacity of the transformer, the power supply department serving the residential life industry will face problems. SUMMARY

[0005] The application aims to provide a method for determining input of charging piles according to transformer redundant capacity, so as to solve the problems in the background.

[0006] To achieve the above-mentioned purpose, the application provides the following technical scheme.

[0007] A method for determining input of charging piles according to transformer redundant capacity, comprising:

[0008] S1, setting a measurement and control box:

[0009] A set of current transformers are installed in a frame type intelligent air circuit breaker in a low voltage incoming line cabinet of a public transformer, a guide rail type multifunctional digital display meter, a programmable controller first PLC, a switching power supply, a three-phase power carrier communication module and a 4G wireless transmitter are installed.

[0010] S2, setting a distribution box:

[0011] The installation of the underground parking lot charging pile floor distribution box, install a leakage protection recloser, a programmable controller second PLC, a switching power supply, a three-phase power carrier communication module, and a liquid crystal display, the distribution box is configured with 15 or 30 63A / 2P high breaking miniature air switches, 15 or 30 multifunctional electronic meters (provided by the power supply department), 15 or 30 63A / 2P leakage protection air switches. A distribution box can allow 15 or 30 charging piles to be connected.

[0012] S3, parking space setting:

[0013] A charging pile with single-phase power carrier communication is installed beside each parking space, which is responsible for providing whether an electric vehicle charging gun has been inserted, charging current data, and whether it has been fully charged for the charging pile distribution box;

[0014] S4, judging whether the charging pile is put into

[0015] When the owner's electric vehicle is parked in the parking space and the charging gun is inserted into the electric vehicle, the charging pile sends a charging request to the second PLC through single-phase power carrier, and the second PLC asks the first PLC whether there is sufficient capacity to allow the charging pile to start charging. The first PLC has set the charging pile to be a 3.5kW or 7kW charging pile, and performs redundant capacity calculation, the formula is:

[0016] n = (90%Ie-I) / In

[0017] Where n is the number of charging piles that can be put into, In is the maximum charging current of 7kW charging pile 32A or 3.5kW charging pile 16A, Ie is the rated current of the transformer, such as the rated current of 630kVA transformer is 909A, I is the measured current, the first PLC calculates n≥1 through the above formula, and the charging pile is turned on for charging, and the charging is started in order according to the time when the charging gun is inserted into the electric vehicle. If I suddenly increases during charging, resulting in n≤1, the first PLC immediately stops the charging pile that is last put into charging, until n≥1 is met. If the charging gun is inserted into the electric vehicle when n≤1, the waiting queue is implemented, and the charging pile that is originally disconnected is charged preferentially after n≥1, and then the charging pile that meets the queue is charged.

[0018] Preferably, the digital display in S1 has RS485 communication, over-limit tripping contact points of programmable opening, and a 5A / 5mA miniature current transformer for data acquisition of the programmable controller first PLC, wherein the first PLC has 3-way current analog quantity acquisition, which is transmitted to the charging pile floor distribution box installed in the underground parking lot through three-phase power carrier, and is transmitted to the after-sales maintenance center through 4G wireless transmission, realizing remote maintenance.

[0019] Preferably, the S2 distribution box is transmitted to the first PLC installed in the low-voltage incoming line cabinet through three-phase power carrier, and in the S2, a set of multifunctional digital display meter is installed in the distribution box, which can set the trip according to 95% of the maximum apparent power, protect the utility transformer, force to stop all electric vehicle charging, and prevent the transformer from being damaged due to overload.

[0020] Compared with the prior art, the beneficial effects of the present application are:

[0021] The present application detects different redundant capacities at different time periods in a day by using the existing transformer capacity, puts into the charging pile with demand, relies on the power carrier technology to communicate the incoming line cabinet, the charging pile distribution box and the charging pile three terminal devices, relies on the programmable controller to judge whether the transformer redundant capacity allows the charging pile to be put into use, solves the problem that the power supply department is worried about whether the transformer is overloaded and damaged, causes the power supply reliability to be reduced, solves the daily increasing demand for installation of charging piles without increasing the basic investment of the power supply department, solves the problem that the valley power is used for electric vehicle charging, achieves the purpose of peak load shifting of the power supply department, achieves the demand that the residential area has a parking space to apply for installation of charging piles, avoids the problem that the power supply department charges, avoids the phenomenon of overload of the transformer caused by the increase of charging load of the power supply department, and protects the power supply department's electric equipment assets. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 The charging pile based on the power carrier communication is put into the remote control flow chart. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0024] Embodiment one:

[0025] Please refer to Figure 1 As shown in the figure, a method for determining the input of charging pile according to transformer redundant capacity, comprising:

[0026] S1, set the measurement and control box:

[0027] A set of current transformers are installed in the frame type intelligent air circuit breaker outlet in the low-voltage incoming line cabinet of the utility transformer, a guide rail type multifunctional digital display meter, a programmable controller first PLC, a switching power supply, a three-phase power carrier communication module and a 4G wireless transmitter are installed in the low-voltage incoming line cabinet of the utility transformer.

[0028] S2, distribution box setting:

[0029] The underground parking lot charging pile floor distribution box is installed with an electric leakage protection recloser, a programmable controller second PLC, a switching voltage stabilizing power supply, a three-phase power carrier communication module, and a liquid crystal display. Inside the distribution box, 15 or 30 63A / 2P high breaking miniature air switches, 15 or 30 multifunctional electronic meters (provided by the power supply department), and 30 or 15 63A / 2P electric leakage protection air switches are configured. One distribution box can allow 15 or 30 charging piles to be connected.

[0030] S3, parking space setting:

[0031] A charging pile with single-phase power carrier communication is installed beside each parking space, which is responsible for providing whether an electric vehicle charging gun has been inserted, charging current data, and whether it has been fully charged for the charging pile distribution box.

[0032] S4, judging charging pile input

[0033] When the owner's electric vehicle is parked in the parking space and the charging gun is inserted into the electric vehicle, the charging pile sends a charging request to the second PLC through single-phase power carrier. The second PLC asks the first PLC whether there is sufficient capacity to allow the charging pile to start charging. The first PLC has set the charging pile to be a 3.5kW or 7kW charging pile, and performs redundant capacity calculation. The formula is:

[0034] n = (90%Ie - I) / In

[0035] Where n is the number of charging piles that can be put into operation, In is the maximum charging current of a 7kW charging pile, which is 32A, or the maximum charging current of a 3.5kW charging pile, which is 16A, Ie is the rated current of the transformer, the rated current of a 630kVA transformer is 909A, and I is the measured current. The first PLC calculates n≥1 through the above formula, turns on the charging of this charging pile, and starts charging in order according to the time when the charging gun is inserted into the electric vehicle. If I suddenly increases during charging, resulting in n≤1, the first PLC immediately stops the charging pile that was last put into operation until n≥1 is met. If the charging gun is inserted into the electric vehicle when n≤1, a waiting queue is implemented, and the charging pile that was disconnected is prioritized when n≥1 is met.

[0036] The digital display in S1 has RS485 communication, programmable over-trip contact, and the current transformer is a 5A / 5mA micro current transformer, which provides the first PLC data acquisition of programmable controller. The first PLC has 3-way current analog acquisition, which is transmitted to the charging pile floor distribution box installed in the underground parking lot through three-phase power carrier, and is transmitted to the after-sales maintenance center through 4G wireless, realizing remote maintenance. The distribution box in S2 transmits to the first PLC installed in the low-voltage incoming line cabinet through three-phase power carrier. In S2, the recloser in the charging pile distribution box can be set according to the maximum apparent power of 95% to trip, protect the utility transformer, and force stop all electric vehicle charging to prevent transformer overload damage.

[0037] As can be seen from the above, the second programmable controller PLC is set in advance by the staff, for example, the charging pile is set to 3.5kW, and the maximum charging current of the charging pile is 16A. When the owner inserts the charging gun into the electric vehicle, the charging pile sends a charging request to the second PLC through single-phase power carrier, and the second PLC inquires the first PLC whether there is redundant capacity to allow the charging pile to start charging. The main PLC calculates n≥1 through the above formula, and opens the charging pile charging. The charging gun is inserted into the electric vehicle in time order, and the charging is started in turn. If I suddenly increases during the charging process, resulting in n≤1, the main PLC immediately stops the last charging pile, until n≥1 is met. If the charging gun is inserted into the electric vehicle when n≤1, the waiting queue is implemented, and after n≥1, the charging pile that is originally disconnected is charged first, and then the charging pile that meets the queue is charged, so that the electric vehicle is reasonably, economically and intelligently charged without increasing the capacity of the transformer.

[0038] Although embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, replacements and changes can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A method for determining a charging station to be put into operation based on transformer redundancy capacity, characterized in that, Specifically comprising the following steps: S1, setting the control box: Install a set of current transformers in the frame type intelligent air circuit breaker outlet of the low voltage incoming line cabinet of the public transformer, a guide rail type multifunctional digital display meter, a programmable controller first PLC, a switching power supply, a three-phase power carrier communication module, and a 4G wireless transmitter; S2, distribution box setting: Install the underground parking lot charging pile floor distribution box, install a leakage protection recloser, a programmable controller second PLC, a switching power supply, a three-phase power carrier communication module, and a liquid crystal display in it. The distribution box can be configured with 15 or 30 63A / 2P high breaking miniature air switches and 15 or 30 multifunctional electronic meters, which are provided by the power supply department. One distribution box can allow 15 or 30 charging piles to be connected. S3, parking space setting: Install a charging pile with single-phase power carrier communication beside each parking space to provide whether the electric vehicle charging gun has been inserted, the charging current data, and whether it has been fully charged. S4, judging the charging pile input When the owner's electric vehicle is parked in the parking space and the charging gun is inserted into the electric vehicle, the charging pile sends a charging request to the second PLC through single-phase power carrier. The second PLC asks the first PLC whether there is sufficient capacity to allow the charging pile to start charging. The first PLC has set the charging pile to be 3.5kW or 7kW, and performs redundant capacity calculation according to the formula: n=(90%Ie-I) / In Where n is the number of charging piles that can be put into operation, In is the maximum charging current of 7kW charging pile 32A or 3.5kW charging pile 16A, Ie is the rated current of the transformer, and 630kVA transformer rated current is 909A. I is the measured current. The first PLC calculates n≥1 through the above formula, opens the charging pile, and starts charging in order according to the time when the charging gun is inserted into the electric vehicle. If I suddenly increases during charging, causing n≤1, the first PLC immediately stops the last charging pile, until n≥1. If the charging gun is inserted into the electric vehicle when n≤1, the waiting queue is implemented, and the disconnected charging pile is prioritized when n≥1.

2. The method of claim 1, wherein the method further comprises: The digital display meter in S1 has RS485 communication, programmable over-trip tripping contacts, and a 5A / 5mA miniature current transformer for data acquisition by the programmable controller first PLC, which has three current analog quantity acquisition channels. The data is transmitted to the charging pile floor distribution box installed in the underground parking lot through three-phase power carrier, and is transmitted to the after-sales maintenance center through 4G wireless transmission, realizing remote maintenance.

3. The method of claim 1, wherein the method further comprises: determining the number of charging piles to be put into operation according to the redundant capacity of the transformer. The distribution box in S2 transmits to the first PLC installed in the low voltage incoming line cabinet through three-phase power carrier. In S2, the recloser in the charging pile distribution box can be set to trip according to the maximum apparent power of 95% to protect the public transformer and force stop all electric vehicle charging to prevent transformer overload and damage.

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