Electric energy router multi-port parallel current sharing control method based on voltage disturbance control

Abstract

The invention relates to an electric energy router multi-port parallel current sharing control method based on voltage disturbance control. The method comprises the steps that S100, a current sharing control processor DSP obtains data of an electric energy router connected with a charging gun in parallel through a CAN communication bus; s200, the current sharing control processor DSP calculates a total current value output by the charging gun according to the received data of the electric energy routers, calculates an average current value which should be output by the electric energy routers connected in parallel according to the total current value, and issues the average current value to the electric energy routers; and S300, inputting the average current value into a PI current-sharing loop for calculation, and adjusting the output current value of the electric energy router, so that the output current value of the electric energy router is equal to the average current value. According to the invention, the current output of the plurality of electric energy routers connected in parallel on the charging gun can be balanced, all the electric energy routers can work in a high-efficiency interval, the charging efficiency is improved, and the electric energy waste is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of multi-port parallel current sharing of an electric energy router, and in particular to a multi-port parallel current sharing control method of an electric energy router based on voltage disturbance control. Background Art

[0002] With the rapid development of new energy electric vehicle technology, high-power electric vehicle charging piles and power routers, as key facilities for electric vehicle energy replenishment, have become the focus of industry attention in terms of performance and efficiency. In order to meet the growing demand for high-power charging of electric vehicles, a multi-channel parallel output connection method is usually used to achieve high-power and high-efficiency power transmission.

[0003] However, in actual applications, when the battery of an electric vehicle is close to being fully charged, due to the inconsistent impedance between each module and the output node, as well as the inconsistent output voltage of the modules, some modules are in a high-power output state, while some modules output almost no power, causing the low-power modules to operate in a low-efficiency range, resulting in a waste of electric energy.

[0004] Therefore, there is an urgent need to provide a multi-port parallel current sharing control method for an energy router based on voltage disturbance control to solve the above problems. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings and defects of the prior art and provide a multi-port parallel current sharing control method for power routers based on voltage disturbance control, so that the current output of multiple power routers connected in parallel on the charging gun is balanced, and they can all work in a higher efficiency range, thereby improving the charging efficiency and reducing the waste of electric energy.

[0006] The objective of the present invention is achieved through the following technical solutions:

[0007] A multi-port parallel current sharing control method for an electric energy router based on voltage disturbance control, comprising:

[0008] S100, the current sharing control processor DSP obtains the data of the power router connected in parallel with the charging gun through the CAN communication bus;

[0009] S200, the current sharing control processor DSP calculates the total current value output by the charging gun according to the received power router data, and calculates the average current value that the parallel power router should output according to the total current value, and then sends the average current value to the power router;

[0010] S300, input the average current value into the PI current sharing loop for calculation, and adjust the output current value of the power router so that the output current value of the power router is equal to the average current value.

[0011] As a preferred technical solution of the present invention, in step S100, the power router data includes location information, connection information, working status information and current working current information of each power router.

[0012] 3. The method for controlling the current sharing of multiple ports of a power router in parallel based on voltage disturbance control according to claim 1, wherein the step S200 is specifically as follows:

[0013] S201, obtaining the working status information and current working current information of the power router connected in parallel with the charging gun according to the address information and connection information of the power router marked in the power router data;

[0014] S202, calculating the total current value of the charging gun according to the working status of the power routers connected in parallel and the current working current;

[0015] S203, judging whether the charging gun is on for current balancing according to the total current value, and if so, calculating the average current value that the power router connected in parallel with the charging gun should output according to the total current value of the charging gun;

[0016] S204, sending the average current value to the power router;

[0017] Among them, the basis for judging whether the charging gun turns on current sharing is whether the calculated total current value output by the charging gun is greater than 1A. If the total current value is greater than 1A, current sharing is turned on; if the total current value is less than 1A, it indicates no load and current sharing is turned off.

[0018] As a preferred technical solution of the present invention, in step S200, the calculation formula of the average current value is:

[0019] As a preferred technical solution of the present invention, the step S300 is specifically that the power router receives data from the current sharing control processor DSP through the CAN communication bus to determine whether to turn on the current sharing; if the current sharing needs to be turned on, the received average current value is set as the given value of the PI current sharing loop;

[0020] The given value and the output current sampling value are input into the PI controller to calculate the voltage disturbance value, and then the voltage disturbance value and the output voltage setting value are calculated to obtain the voltage loop given value, and the voltage loop given value and the output voltage value of the controlled object collected in real time are input into the PI controller to calculate the current loop setting value; then the output current value of the controlled object collected in real time and the calculated current loop setting value are input into the PI controller to calculate the control signal value, and the control signal value is output to the controlled object so that the current output by the controlled object is close to the average current value; wherein, the judgment basis for judging whether the power router turns on current sharing is the working status of the power router and the current working current recorded in the power router data. When the working status of the power router is online and the current working current is not equal to the average current value, the current sharing is turned on.

[0021] As a preferred technical solution of the present invention, the calculation formula of the PI controller is:

[0022] uk0=uk1+udk,udk=kp*(ek0-ek1)+ki*ek0

[0023] Among them, kp is the proportional coefficient, ki is the integral coefficient, uk1 is the last output value, ek0 is the current error value, ek1 is the last error value, and uk0 is the current output value.

[0024] As a preferred technical solution of the present invention, before step S100, the control method further includes:

[0025] S11, setting the voltage value at which the charging gun stops working;

[0026] S12, setting any one of the multiple power routers connected in parallel to the charging gun as the host, and the rest as slaves, the host does not turn on current balancing, and the slaves turn on current balancing;

[0027] S13. The host reads the current working voltage of the load and compares it with the set stop working voltage value. When the current working voltage of the load is lower than the set voltage value, the host sends a command to the slave through the CAN communication bus to control the PI current sharing loop in the slave and adjust the output current of each slave. When the current working voltage of the load is equal to the set voltage, the host determines that the load is fully charged and sends a stop charging command to the slave through the CAN communication bus. After receiving the command, the slave closes the PI current sharing loop and stops outputting current.

[0028] As a preferred technical solution of the present invention, in the control method, the current sharing control processor DSP communicates with the power router using a CAN bus, and the control chip model of the current sharing control processor DSP is TMS320F280049.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] The present invention is based on voltage disturbance control to balance the output current of the power router, avoid affecting the stability of the charging pile system due to uneven current output, and can work in a higher efficiency range, improve charging efficiency and reduce energy waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic flow chart of the control method of the present invention.

[0032] Figure 2 It is a connection diagram of the current sharing control processor DSP and the power router of the present invention.

[0033] Figure 3 A control loop block diagram of a power router of the present invention with a current sharing loop added thereto. DETAILED DESCRIPTION

[0034] The present invention is further described in detail below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0035] The specific implementation process of the present invention is as follows:

[0036] like Figure 1 to Figure 2 As shown, a multi-port parallel current sharing control method of an electric energy router based on voltage disturbance control includes:

[0037] S100, the current sharing control processor DSP obtains the data of the power routers connected in parallel to the charging gun through the CAN communication bus; in an embodiment of the present invention, the power router data includes the location information, connection information, working status information and current working current information of each power router. Specifically, the current sharing control processor DSP obtains the data of each power router, including the power router location identification data and the connection status identification data. Since the charging pile is connected to multiple charging guns, the position identification of the power router is used to determine which charging gun each power router is connected to. In this way, the number of power routers connected in parallel to each charging gun and the current working status and current working current of each power router are obtained through analysis. The working status includes whether the power router is online, offline, or faulty. The online state indicates that the power router is working and needs to participate in current sharing; the offline or faulty state indicates that the power router is not working and does not need to participate in starting current sharing.

[0038] S200, the current sharing control processor DSP calculates the total current value output by the charging gun according to the received power router data, and calculates the average current value that the parallel power router should output according to the total current value, and then sends the average current value to the power router. Specifically, the following steps are included:

[0039] S201, obtaining the working status information and current working current information of the power router connected in parallel with the charging gun according to the address information and connection information of the power router marked in the power router data;

[0040] S202, calculating the total current value of the charging gun according to the working status of the power routers connected in parallel and the current working current;

[0041] S203, judging whether the charging gun is on for current balancing according to the total current value, and if so, calculating the average current value that the power router connected in parallel with the charging gun should output according to the total current value of the charging gun;

[0042] S204, sending the average current value to the power router;

[0043] Among them, the basis for judging whether the charging gun turns on current sharing is whether the calculated total current value output by the charging gun is greater than 1A. If the total current value is greater than 1A, current sharing is turned on; if the total current value is less than 1A, it means no load and current sharing is turned off.

[0044] The average current value is calculated as:

[0045]

[0046] Specifically, since the charging pile is connected to multiple charging guns, the total output current value of each charging gun needs to be calculated separately and calculated from the received power router data. The total current value is calculated based on the current working current and working status of the power router connected in parallel with the charging gun, and then the average current value that each power router connected in parallel with the charging gun should output is calculated based on the average current value calculation formula. And mark whether each power router needs to turn on current sharing, and then send the mark data and average current value to the power router through the CAN communication bus.

[0047] S300, input the average current value into the PI current sharing loop for calculation, and adjust the output current of the power router so that the output current value of the power router is equal to the average current value.

[0048] like Figure 3 As shown, in an embodiment of the present invention, step S300 is specifically that the power router receives data from the current sharing control processor DSP through the CAN communication bus to determine whether to turn on current sharing; if current sharing needs to be turned on, the received average current value is set as a given value of the PI current sharing loop.

[0049] The given value and the output current sampling value are input into the PI controller to calculate the voltage disturbance value, and then the voltage disturbance value and the output voltage setting value are calculated to obtain the voltage loop given value. The voltage loop given value and the output voltage value of the controlled object collected in real time are input into the PI controller to calculate the current loop setting value. The output current value of the controlled object collected in real time and the calculated current loop setting value are then input into the PI controller to calculate the control signal value, and the control signal value is output to the controlled object so that the output current of the controlled object is close to the average current value.

[0050] Among them, the basis for judging whether the power router needs to turn on current sharing is the working status of the power router and the current working current recorded in the power router data. Specifically, the identification data below the current sharing control processor DSP includes an identification of whether to turn on current sharing, but because the host does not turn on current sharing, and the host is not a fixed power router, it needs to be re-determined. When the working status of the power router is online and the current working current is not equal to the average current value, current sharing is turned on; if the working status is online, but the working current is equal to the average current value, current sharing is not turned on; if the working status is faulty or offline, current sharing is not turned on.

[0051] The PI controller calculation formula is:

[0052] uk0=uk1+udk,udk=kp*(ek0-ek1)+ki*ek0

[0053] Among them, kp is the proportional coefficient, ki is the integral coefficient, uk1 is the last output value, ek0 is the current error value, ek1 is the last error value, and uk0 is the current output value.

[0054] Specifically, the output current sampling value is the current working current value of the power router, and the output voltage setting value is the load request voltage value. The output current sampling value of the power router is obtained by real-time sampling of the working current of the power router. The output current sampling value and the average current value calculated in step S200 are used to calculate the voltage disturbance value through the PI controller calculation formula. The control signal value is calculated by continuously sampling data in real time in the PI current sharing loop, and then the control signal value is output to the controlled object, and the output voltage of the controlled object is adjusted so that the output current of the power router is equal to the average current value. After adjusting the output voltage, the PI current sharing loop samples the output voltage and output current of the power router again, and compares them with the preset value to ensure that the output current can be continuously adjusted until the current of the power router is close to the average current value. Through the PI current sharing loop, the error can be gradually reduced so that the output current of all power routers is close to the average current value, thereby realizing current sharing control.

[0055] In an embodiment of the present invention, before step S100, the control method further includes:

[0056] S11, setting the voltage value at which the charging gun stops working;

[0057] S12, setting any one of the multiple power routers connected in parallel to the charging gun as the host, and the rest as slaves, the host does not turn on current balancing, and the slaves turn on current balancing;

[0058] S13. The host reads the current working voltage of the load and compares it with the set stop working voltage value. When the current working voltage of the load is lower than the set voltage value, the host sends a command to the slave through the CAN communication bus to control the PI current sharing loop in the slave and adjust the output current of each slave. When the current working voltage of the load is equal to the set voltage, the host determines that the load is fully charged and sends a stop charging command to the slave through the CAN communication bus. After receiving the command, the slave closes the PI current sharing loop and stops outputting current.

[0059] Specifically, the present invention adds a voltage loop pre-calibration on the basis of the voltage and current dual closed-loop control. One of the power routers connected in parallel in the charging gun is selected as the host, and the other power routers are slaves. The host is set to one, which can be any power router in the charging gun. If the host does not turn on current sharing, the voltage loop of the host will not be affected by the voltage disturbance control. If the slave turns on current sharing, the voltage loop of the slave will add voltage disturbance control. When the output current distribution of the power router of the charging gun is uneven, its output voltage is adjusted through the PI current sharing loop and the voltage disturbance value to achieve matching with the output voltage of the host. Since the host does not turn on the current sharing loop, the host output voltage is equal to the set voltage. In the final stage of charging, the current of the host will decrease first, resulting in a decrease in the total current, and then the average current value will decrease. The reduction in the average current value will reduce the output voltage of the slave through the PI current sharing loop, thereby avoiding overcharging caused by the increase in the charging gun voltage.

[0060] In an embodiment of the present invention, the current sharing control processor DSP communicates with the power router of the charging gun using the CAN bus, which has strong anti-interference performance and can communicate bidirectionally between bus nodes. The CAN communication lines of all power routers connected in parallel to the charging gun are connected to the CAN communication interface of the current sharing control processor DSP, and the current sharing control processor DSP can communicate with multiple power routers at the same time. The control chip model of the current sharing control processor DSP is TMS320F280049, which has a built-in CAN bus module and has CAN communication function.

[0061] The above-mentioned embodiments only express the implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be based on the attached claims.

Claims

1. A method for controlling the current sharing of multi-port parallel connection of power routers based on voltage disturbance control, characterized in that: include: S100, the current sharing control processor DSP obtains the data of the power router connected in parallel with the charging gun through the CAN communication bus; S200, the current sharing control processor DSP calculates the total current value output by the charging gun according to the received power router data, and calculates the average current value that the parallel power router should output according to the total current value, and then sends the average current value to the power router; S300, input the average current value into the PI current sharing loop for calculation, and adjust the output current value of the power router so that the output current value of the power router is equal to the average current value.

2. According to the method of claim 1, a multi-port parallel current sharing control method of an electric energy router based on voltage disturbance control is characterized in that: In the step S100, the power router data includes the location information, connection information, working status information and current working current information of each power router.

3. According to the method of claim 1, a multi-port parallel current sharing control method of an electric energy router based on voltage disturbance control is characterized in that: The step S200 is specifically as follows: S201, obtaining the working status information and current working current information of the power router connected in parallel with the charging gun according to the address information and connection information of the power router marked in the power router data; S202, calculating the total current value of the charging gun according to the working status of the power routers connected in parallel and the current working current; S203, judging whether the charging gun is on for current balancing according to the total current value, and if so, calculating the average current value that the power router connected in parallel with the charging gun should output according to the total current value of the charging gun; S204, sending the average current value to the power router; Among them, the basis for judging whether the charging gun turns on current sharing is whether the calculated total current value output by the charging gun is greater than 1A. If the total current value is greater than 1A, current sharing is turned on; if the total current value is less than 1A, it indicates no load and current sharing is turned off.

4. According to claim 3, a method for controlling the current sharing of multiple ports in parallel of an electric energy router based on voltage disturbance control is characterized in that: In step S200, the calculation formula of the average current value is:

5. According to the method of claim 1, a multi-port parallel current sharing control method of an electric energy router based on voltage disturbance control is characterized in that: Specifically, the step S300 includes: the power router receives data from the current sharing control processor DSP through the CAN communication bus to determine whether to start current sharing; if current sharing needs to be started, the received average current value is set as the given value of the PI current sharing loop; Input the given value and the output current sampling value into the PI controller to calculate the voltage disturbance value, then calculate the voltage disturbance value and the output voltage setting value to obtain the voltage loop given value, input the voltage loop given value and the output voltage value of the controlled object collected in real time into the PI controller to calculate the current loop setting value, then input the output current value of the controlled object collected in real time and the calculated current loop setting value into the PI controller to calculate the control signal value, and output the control signal value to the controlled object so that the output current of the controlled object is close to the average current value; Among them, the judgment basis for judging whether the power router turns on current sharing is the working status of the power router and the current working current recorded in the power router data. When the working status of the power router is online and the current working current is not equal to the average current value, current sharing is turned on.

6. The method for controlling the current sharing of multiple ports of a power router in parallel based on voltage disturbance control according to claim 5 is characterized in that: The calculation formula of PI controller is: uk0=uk1+udk,udk=kp*(ek0-ek1)+ki*ek0 Among them, kp is the proportional coefficient, ki is the integral coefficient, uk1 is the last output value, ek0 is the current error value, ek1 is the last error value, and uk0 is the current output value.

7. The method for controlling the current sharing of multiple ports of a power router in parallel based on voltage disturbance control according to claim 1 is characterized in that: Before step S100, the control method further includes: S11, setting the voltage value at which the charging gun stops working; S12, setting any one of the multiple power routers connected in parallel to the charging gun as the host, and the rest as slaves, the host does not turn on current balancing, and the slaves turn on current balancing; S13. The host reads the current working voltage of the load and compares it with the set stop working voltage value. When the current working voltage of the load is lower than the set voltage value, the host sends a command to the slave through the CAN communication bus to control the PI current sharing loop in the slave and adjust the output current of each slave. When the current working voltage of the load is equal to the set voltage, the host determines that the load is fully charged and sends a stop charging command to the slave through the CAN communication bus. After receiving the command, the slave closes the PI current sharing loop and stops outputting current.

8. The method for controlling the current sharing of multiple ports of a power router in parallel based on voltage disturbance control according to claim 1 is characterized in that: In the control method, the current sharing control processor DSP communicates with the power router using a CAN bus, and the control chip model of the current sharing control processor DSP is TMS320F280049.

Images