An electric bicycle charging protection system and its control method

Abstract

The present invention discloses an electric bicycle charging protection system and its control method, which sequentially includes an AC management unit, a charger, a DC management unit, and a temperature control unit; one end of the AC management unit is electrically connected to the mains power supply, one end of the DC management unit is electrically connected to the output end of the charger and the other end is electrically connected to the charging socket of the electric bicycle; the AC management unit detects the AC current, AC voltage, and loop leakage current, and the DC management unit detects the charging current and DC voltage output by the charger; the temperature monitoring unit detects the ambient temperature, battery temperature, and the proximity switch closing state reflecting whether the temperature monitoring unit is stably adsorbed on the surface of the battery pack. The present invention realizes the comprehensive protection of the electric bicycle charging system and ensures the reliability and accuracy of charging intelligent control.

Description

Technical Field

[0001] The present invention belongs to the technical field of electric bicycles, and particularly relates to an electric bicycle charging protection system and a control method thereof.

Background Art

[0002] With the increasing number of electric bicycles in China, the charging safety problem of electric bicycles has become increasingly serious. How to ensure that electric bicycles avoid problems such as catching fire and spontaneous combustion during charging urgently needs to be solved. In the prior art, the patent publication number CN108988450B discloses an intelligent charger and charging method for electric bicycles with fire and explosion prevention functions. Although the charging strategy is designed by monitoring the voltage, current, and temperature of the battery, in actual use, the monitoring of the battery temperature is sometimes inaccurate, mainly because the sensor for monitoring the battery temperature sometimes falls off after the bicycle travels for a long time and bumps; and there is a lack of detection of the mains voltage. When the mains voltage is out of the allowable charging voltage range due to fluctuations, the charger will also charge, which poses a safety hazard and has a serious impact on the service life of the battery.

[0003] Therefore, a new electric bicycle charging protection system and a control method thereof are needed to solve the above problems.

Summary of the Invention

[0004] One of the main objects of the present invention is to provide an electric bicycle charging protection system, which realizes various protections for electric vehicle charging, avoids safety problems caused by incorrect charging, abnormal charging, too high battery pack temperature, or inaccurate battery temperature detection, and also avoids the occurrence of electric vehicle fires caused by short circuits, overloads, battery pack overheating, etc. during electric vehicle charging.

[0005] The present invention realizes the above object through the following technical solutions: An electric bicycle charging protection system includes a charger and a DC management unit B, and further includes an AC management unit A and a temperature control unit C provided on the battery pack; one end of the AC management unit A is electrically connected to the mains and the other end is electrically connected to the input end of the charger; one end of the DC management unit B is electrically connected to the output end of the charger and the other end is electrically connected to the charging socket of the electric bicycle;

[0006] The AC management unit A includes a microprocessor and its peripheral circuit AC-MU, an AC voltage processing circuit AC-U, an RF communication module RF1, a Bluetooth communication module BT, a static switch DK, and an AC current processing circuit AC-I, which are electrically connected to the microprocessor and its peripheral circuit AC-MU. It also includes a voltage transmitter TV, a plug JP1, and a socket JP2. One end of the plug JP1 is connected to the mains power supply, and the other end is electrically connected to the socket JP2. The voltage transmitter TV collects the mains AC voltage Uac accessed by the plug JP1 and transmits it to the AC voltage processing circuit AC-U. The static switch DK is set on the connection line between the plug JP1 and the socket JP2 and is controlled by the microprocessor and its peripheral circuit AC-MU for its on / off state. On the connection line between the plug JP1 and the socket JP2, there are also a current transformer CT1 for detecting the input mains AC current Iac and a current transformer CT2 for detecting the loop leakage current Ild. The detection data of the current transformers CT1 and CT2 are uploaded to the AC current processing circuit AC-I. The socket JP2 is electrically connected to the input end of the charger.

[0007] The DC management unit B includes a microprocessor and its peripheral circuit DC-MU, a DC voltage measurement circuit DC-U, a DC current measurement circuit DC-I, and an RF communication module RF2, which are electrically connected to the microprocessor and its peripheral circuit DC-MU. It also includes a plug JP3 and a socket JP4. The socket JP4 is electrically connected to the charging socket of the electric bicycle. The DC voltage measurement circuit DC-U collects the charging DC voltage Udc output by the charger, and the DC current measurement circuit DC-I collects the charging current Idc output by the charger and transmits them to the microprocessor and its peripheral circuit DC-MU. A DC relay is set on the connection line between the plug JP3 and the socket JP4, and the DC relay is controlled by the microprocessor and its peripheral circuit DC-MU to achieve on / off switching.

[0008] The temperature control unit C includes a microprocessor and its peripheral circuit WK-MU, an ambient temperature sensor T1, an infrared thermopile sensor T2, a capacitive proximity switch, and an RF communication module RF3, which are electrically connected to the microprocessor and its peripheral circuit WK-MU. The temperature control unit C is adsorbed on the battery pack of the electric bicycle through a strong suction cup as a whole, and the capacitive proximity switch is arranged on the side close to the battery surface. The infrared thermopile sensor T2 collects the battery pack temperature and transmits it to the microprocessor and its peripheral circuit WK-MU.

[0009] Furthermore, the AC management unit A further includes a power supply circuit PW1 electrically connected to the microprocessor and its peripheral circuit AC-MU.

[0010] Furthermore, the AC management unit A further includes a touch screen HMI electrically connected to the microprocessor and its peripheral circuit AC-MU, which is used for users to set system parameters.

[0011] Further, the DC management unit B further includes a wide-input DC power supply module PW2 electrically connected to the microprocessor and the peripheral circuit DC-MU.

[0012] Further, the temperature control unit C further includes a button battery for supplying power to the microprocessor and the peripheral circuit WK-MU, a DC power supply circuit provided between the button battery and the microprocessor and the peripheral circuit WK-MU, and a power detection circuit for detecting the battery level of the button battery. The power detection circuit collects the battery level of the button battery and transmits it to the microprocessor and the peripheral circuit WK-MU.

[0013] Another object of the present invention is to provide a control method for an electric bicycle charging protection system, which includes:

[0014] S1) Read the system set parameters; the system set parameters include the minimum allowable voltage Uacmin of the charger, the maximum allowable voltage Uacmax of the charger, the rated power S of the charger, the leakage protection current Ildset of the charger, the maximum charging current Idcmax of the battery, the floating charge voltage value Udco at -30°C, the floating charge voltage value Udcp at 50°C, the maximum allowable charging time Tcmax, the minimum allowable charging ambient temperature T0min, the maximum allowable charging ambient temperature T0max, and the battery temperature protection value Tobjmax;

[0015] S2) Collect the system measurement parameters: obtain the measured values of the mains voltage Uac, the charger AC terminal current Iac, and the charger AC terminal leakage value Ild through the AC management unit A; obtain the charger DC current Idc, the charging DC voltage Udc-c, and the battery floating voltage Udc-k by reading the data of the DC management unit B through radio frequency communication; obtain the ambient temperature measurement value T0, the battery temperature measurement value Tobj, and the adsorption state BTON of the capacitive proximity switch by reading the data of the temperature control unit C through radio frequency communication;

[0016] S3) Calculate the calculated parameters:

[0017] The charger current rating Ie = S / 220V,

[0018] The charging overload current Iod = 1.2Ie,

[0019] The charging overcurrent Ioc = 3Ie,

[0020] The battery floating charge voltage value Udcz = Udco + Kp × T0, where Kp = (Udcp - Udco) / 80;

[0021] S4) Determine whether the charging permission conditions (1), (2), and (3) are all satisfied. If so, proceed to the next step. If not, set the charging flag FLAG to 3 and execute step S8). The charging permission condition (1) is Uacmin < Uac < Uacmax; the charging permission condition (2) is T0min < T0 < T0max; the charging permission condition (3) is that BTON is in the closed state.

[0022] S5) Determine whether the charging non - permission conditions (4), (5), (6), (7), and (8) are satisfied. If any one of the conditions is satisfied, set FLAG to 4 to indicate that a charging protection action is taken and execute step S8). If all five conditions are not satisfied, proceed to the next step. The charging non - permission condition (4) is Ild > Ildset; the charging non - permission condition (5) is Iac > Iod; the charging non - permission condition (6) is Iac > Ioc; the charging non - permission condition (7) is Idc > Idcmax; the charging non - permission condition (8) is Tobj > Tobjmax.

[0023] S6) Determine whether the charging permission conditions (9) and (10) are both satisfied. If so, it indicates normal charging and the charging time Tch is counted. Otherwise, set FLAG to 5 to indicate abnormal charging and execute step S8). The charging permission condition (9) is Udc - c < Udcz + 3; the charging permission condition (10) is Udc - k < 1.2×Udcz.

[0024] S7) Determine whether the charging time Tch reaches the maximum charging time Tcmax. If so, set FLAG to 2 to indicate that charging is complete and proceed to the next step. Otherwise, return to step S2).

[0025] S8) Disconnect the static switch DK to turn off charging.

[0026] Furthermore, the control process of the DC management unit includes: controlling the JK signal to close the DC relay to obtain the DC charging voltage Udc - c and the DC charging current Idc; controlling the JK signal to open the DC relay to measure the floating voltage Udc - k of the battery pack when not charging. The DC management unit B sends the three data of Udc - c, Udc - k, and Idc to the AC management unit A through radio frequency wireless communication.

[0027] Further, the control process of the temperature control unit C includes: detecting the BTON status of the capacitive proximity switch. If the temperature control unit C has been adsorbed on the battery pack, the status of BTON is 1; otherwise, the status is 0. Reading the data of the ambient temperature sensor T1 to obtain the ambient temperature T0; reading the data of the infrared thermopile sensor T2 to obtain the battery temperature Tobj. The temperature control unit C sends the BTON status, the ambient temperature T0, and the battery pack temperature Tobj to the AC management unit A through radio frequency wireless communication.

[0028] Compared with the prior art, the beneficial effects of an electric bicycle charging protection system and its control method of the present invention are as follows: Three modules are added on the basis of the original charger, namely an AC management unit, a DC management unit, and a temperature control unit, realizing functions such as automatic protection of the charger, automatic shutdown of the charging time, and temperature protection, and can effectively avoid safety risk problems caused by incorrect charging, abnormal charging, too high battery pack temperature, short circuit, overload, etc. Among them, in the AC management unit, a touch screen and a Bluetooth connection to the mobile phone APP are set, which is convenient for users to customize the system parameters of the charging control on the touch screen or the mobile phone APP side, and thus can meet the charging protection control of various different brand models of battery packs, with strong versatility and greater flexibility. In the temperature control unit, a proximity switch that detects whether it is fully attached to the battery pack is set to ensure the accuracy of the sensor detection data in the temperature control unit, and charging is only allowed when the proximity switch is in the closed state, ensuring the reliability of the charging protection control. A static switch for controlling the on / off of the charger power supply is set in the AC management unit. When charging is not allowed, the power connection is directly disconnected, fundamentally stopping the charging, which is more reliable and safe.

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is the overall framework schematic diagram of the embodiment of the present invention;

[0030] Figure 2 It is the structural block diagram of the AC management unit, DC management unit, and temperature control unit in the embodiment of the present invention;

[0031] Figure 3 It is the control flow chart of the embodiment of the present invention;

[0032] Figure 4 It is the control flow chart of the DC management unit in the embodiment of the present invention;

[0033] Figure 5 It is the control flow chart of the temperature control unit in the embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] Embodiment:

[0035] Please refer toFigure 1 - Figure 2 , this embodiment is an electric bicycle charging protection system, which includes an AC management unit A connected to the mains socket end, an electric bicycle charger electrically connected to the AC management unit A, a DC management unit B electrically connected to the DC output end of the electric bicycle charger, and a temperature control unit C provided on the electric bicycle battery. The output end of the DC management unit B is connected to the charging socket of the electric bicycle. The AC management unit A communicates with the DC management unit B and the temperature control unit C through RF radio frequency signals, and the AC management unit A communicates with the mobile phone APP through Bluetooth signals.

[0036] The AC management unit A is responsible for the core control of the entire system. It includes a microprocessor and its peripheral circuit AC-MU, an AC voltage processing circuit AC-U, a voltage transmitter TV, a power supply circuit PW1, a radio frequency communication module RF1, a Bluetooth communication module BT, a touch screen HMI, a static switch DK, an AC current processing circuit AC-I, a plug JP1, and a socket JP2. The microprocessor and its peripheral circuit AC-MU are electrically connected to the AC voltage processing circuit AC-U, the power supply circuit PW1, the radio frequency communication module RF1, the Bluetooth communication module BT, the touch screen HMI, the static switch DK, and the AC current processing circuit AC-I. The AC management unit A is connected to the mains socket end through the plug JP1, and the plug JP1 is electrically connected to the socket JP2. The input end of the voltage transmitter TV is connected to the mains electricity accessed by the plug JP1 and the output end is connected to the AC voltage processing circuit AC-U to detect the AC voltage Uac of the input mains electricity. The input end of the power supply circuit PW1 is connected to the mains electricity accessed by the plug JP1 and the output end is connected to the microprocessor and its peripheral circuit AC-MU to supply power to the microprocessor and its peripheral circuit AC-MU. The static switch DK is provided on the connection line between the plug JP1 and the socket JP2 to control the on / off of this line. Current transformers CT1 for detecting the AC current Iac of the input mains electricity and CT2 for detecting the loop leakage current Ild are also provided on the connection line between the plug JP1 and the socket JP2, and the detection data of the current transformers CT1 and CT2 are uploaded to the AC current processing circuit AC-I. The socket JP2 is electrically connected to the input end of the electric bicycle charger.

[0037] The AC management unit A realizes data communication with the DC management unit B and the temperature control unit C through the radio frequency communication module RF1. The Bluetooth communication module BT is used for communicating with the mobile phone APP application. The operator can perform functions such as parameter setting and status indication in the mobile phone APP application.

[0038] The DC management unit B is mainly responsible for the DC output detection of the electric bicycle charger and the detection of the charging status of the battery pack in the electric bicycle. It includes a microprocessor and its peripheral circuit DC-MU, a wide-input DC power module PW2, a DC voltage measurement circuit DC-U, a DC current measurement circuit DC-I, a radio frequency communication module RF2, a plug JP3, and a socket JP4. The microprocessor and its peripheral circuit DC-MU are electrically connected to the DC voltage measurement circuit DC-U, the DC current measurement circuit DC-I, and the radio frequency communication module RF2. The plug JP3 is electrically connected to the socket JP4, and the plug JP3 is electrically connected to the output terminal of the electric bicycle charger. The socket JP4 is plugged into the charging socket of the electric bicycle to achieve electrical connection. The input terminal of the DC voltage measurement circuit DC-U is electrically connected to the output voltage of the electric bicycle charger connected by the plug JP3, collects the charging DC voltage Udc, and transmits it to the microprocessor and its peripheral circuit DC-MU. The input terminal of the DC current measurement circuit DC-I is electrically connected to the output current of the electric bicycle charger connected by the plug JP3, collects the charging current Idc, and transmits it to the microprocessor and its peripheral circuit DC-MU. A DC relay is provided on the connection line between the plug JP3 and the socket JP4, and the DC relay is controlled by the microprocessor and its peripheral circuit DC-MU to achieve on-off switching, which is used to monitor the charging status of the battery pack. The radio frequency communication module RF2 is used for data communication with the AC management unit A. The input terminal of the wide-input DC power module PW2 is electrically connected to the output voltage of the electric bicycle charger connected by the plug JP3 and is electrically connected to the microprocessor and its peripheral circuit DC-MU.

[0039] The temperature control unit C is mainly responsible for ambient temperature detection and battery temperature detection, and sends the detected temperature signal to the AC management unit A through the RF module. It includes a microprocessor and its peripheral circuit WK-MU, a DC power supply circuit electrically connected to the microprocessor and its peripheral circuit WK-MU, a power detection circuit, an ambient temperature sensor T1, an infrared thermopile sensor T2, a capacitive proximity switch, and a radio frequency communication module RF3. The temperature control unit C is adsorbed on the battery pack of the electric bicycle through a strong suction cup as a whole, and the capacitive proximity switch is arranged on the side close to the battery surface. The microprocessor and its peripheral circuit WK-MU are powered by a button battery through a DC power supply current, and the power detection circuit is used to detect the power of the button battery and transmit the detection result to the microprocessor and its peripheral circuit WK-MU. The capacitive proximity switch is mainly used to detect whether the temperature control unit C has been adsorbed on the battery pack. If it is adsorbed on the battery pack, the capacitive proximity switch closes, and the microprocessor and its peripheral circuit WK-MU wirelessly communicate the state to the AC management unit A through the radio frequency communication module RF3, and the AC management unit A allows the static switch DK to close for charging.

[0040] In this embodiment, three modules are added to the original charger of the electric bicycle, namely, an AC management unit A, a DC management unit B, and a temperature control unit C. The AC management unit A is installed at the upper end of the charger to control the connection or disconnection of the charger power supply. The DC management unit B is installed between the DC output of the charger and the charging interface of the electric vehicle to detect the charging voltage and charging current during the charger operation and the charging status of the battery pack. The temperature control unit C is adsorbed on the battery pack of the electric bicycle (when the battery pack is exposed) or near the battery pack (when the battery pack is not exposed) to measure the charging temperature and ambient temperature of the battery pack. The temperature control unit C must be installed reliably. Only after the capacitive proximity switch detects a closed signal and transmits it to the AC management unit A, will the AC management unit A close the static switch DK to allow the charger to charge, effectively avoiding abnormal charging caused by inaccurate detection data when the sensor for detecting the battery temperature falls off, and further reducing the safety risk.

[0041] This embodiment also provides a control method for an electric bicycle charging protection system, which includes:

[0042] First, parameter setting: It includes system setting parameters, system measurement parameters, control quantity and acquisition quantity parameters, and calculation parameters.

[0043] The parameter names and parameter descriptions of the system setting parameters are shown in Table 1; the setting of the system setting parameters can be performed on the mobile phone APP application or through the touch screen HMI; corresponding data can be obtained according to the battery pack brand of the battery-powered vehicle and the charger instruction manual during the setting, or default parameters can be used.

[0044] Table 1 System setting parameters

[0045] Set parameter name Parameter description Uacmin (V) Minimum voltage allowed by the charger Uacmax (V) Maximum voltage allowed by the charger S (VA) Rated power of the charger / 0.8 Ildset (A) Leakage protection current of the charger Idcmax (A) Maximum charging current of the battery Udco (-30°C) Float charge voltage value at -30°C Udcp (50°C) Float charge voltage value at 50°C Tcmax (h) Maximum allowable charging time T0min (°C) Minimum ambient temperature allowed for charging T0max (°C) Maximum ambient temperature allowed for charging Tobjmax (°C) Battery temperature protection value

[0046] The parameter names, parameter descriptions, and the unit modules where they are located of the system measurement parameters are shown in Table 2.

[0047] Table 2 System measurement parameters

[0048] Measured parameter name Parameter description Unit module where it is located Uac (V) Measured mains voltage AC management unit A Iac (A) Charger current (AC side) AC management unit A Ild (mA) Leakage value of the charger AC management unit A Idc (A) Charger DC current DC management unit B Udc-c (V) Charging DC voltage DC management unit B Udc-k (V) Battery floating voltage DC management unit B T0(℃) Measured ambient temperature value Temperature control unit C Tobj (°C) Measured battery temperature value Temperature control unit C

[0049] The parameter names, parameter descriptions, and the implementation objects of the control quantity (DO) and acquisition quantity (DI) parameters are shown in Table 3.

[0050] Table 3 Control quantity (DO) and acquisition quantity (DI)

[0051] Name of control quantity / acquisition quantity Parameter description DO / DI Object SW_CTR Control the charger to turn on and off DO DK static switch JK Control DC voltage measurement DO DC relay BTON Adsorption state of temperature control unit C DI Capacitive proximity switch

[0052] The parameter names, parameter descriptions, calculation formulas, and functions of the calculation parameters are shown in Table 4.

[0053] Table 4 Calculation Parameters

[0054]

[0055] Second, set the charging conditions: The conditions for allowing the electric bicycle to charge in this embodiment are shown in Table 5.

[0056] Table 5 Charging Conditions

[0057]

[0058] Third, charging control: When the charging permission conditions described in Table 5 are met, the AC management unit A controls the SW_CTR signal to close the static switch DK, enables the charger to work, and counts the cumulative charging time Tch; when the charging conditions are not met, the AC management unit A controls the SW_CTR signal to open the static switch DK, stops charging and displays a stop message on the touch screen HMI; at the same time, a stop message is prompted in the mobile phone APP application.

[0059] The control flow of the AC management unit A is as Figure 3 shown, and it includes:

[0060] S1) Read the system set parameters and set the charging flag FLAG to 0;

[0061] S2) Collect system measurement parameters: Obtain the measured values Uac, Iac, and Ild through data sampling by the AC management unit A; obtain Idc, Udc-c, and Udc-k by reading the DC management unit B through radio frequency communication; obtain T0, Tobj, and the BTON status by reading the temperature control unit C through radio frequency communication;

[0062] S3) Calculate the calculation parameters: Calculate Ie = S / 220V, Iod = 1.2Ie, Ioc = 3Ie, Udcz = Udco + Kp × T0, Kp = (Udcp - Udco) / 80;

[0063] S4) Determine whether the charging flag is 0. If so, control the SW_CTR to close the static switch DK, enable the charger to work, and set the charging flag FLAG to 1; if not, determine whether the charging flag FLAG is 1. If so, proceed to the next step; if not, execute step S9);

[0064] S5) Determine whether the charging permission conditions (1), (2), and (3) are all met. If so, proceed to the next step; if not, set the charging flag FLAG to 3 and execute step S9);

[0065] S6) Determine whether the charging disallowance conditions (4), (5), (6), (7), and (8) are satisfied. If any one of the conditions is satisfied, set FLAG to 4 to indicate that a charging protection action is performed, and execute step S9). If none of the five conditions are satisfied, proceed to the next step;

[0066] S7) Determine whether the charging conditions (9) and (10) are both satisfied. If they are satisfied, it indicates normal charging, and the charging time Tch is counted. Otherwise, set FLAG to 5 to indicate abnormal charging, and execute step S9);

[0067] S8) Determine whether the charging time Tch reaches the maximum charging time, that is, whether condition (11) is satisfied. If it is satisfied, set FLAG to 2 to indicate that charging is complete, and proceed to the next step; otherwise, return to step S2);

[0068] S9) Control SW_CTR to disconnect and turn off the static switch DK to stop charging.

[0069] The DC management unit B mainly measures the charging condition of the charger for the battery pack. Its control flow is as Figure 4 shown. It includes: controlling the JK signal to close the DC relay to obtain the DC charging voltage Udc-c and the DC charging current Idc; controlling the JK signal to open the DC relay to measure the floating voltage Udc-k of the battery pack when not charging. The DC management unit B sends the three data of Udc-c, Udc-k, and Idc to the AC management unit A through radio frequency wireless communication.

[0070] The temperature control unit C mainly detects the BTON status of the capacitive proximity switch, the ambient temperature T0, the battery pack temperature Tobj, and the button battery power Avq. Its control flow is as Figure 5 shown. It includes: detecting the BTON status of the capacitive proximity switch. If the temperature control unit C has been adsorbed on the battery pack, the status of BTON is 1, otherwise the status is 0; detecting the button battery power Avq and monitoring the power supply situation inside the temperature control unit C. If the power is too low, the battery needs to be replaced in time; reading the data of the ambient temperature sensor T1 to obtain the ambient temperature T0; reading the data of the infrared thermopile sensor T2 to obtain the battery temperature Tobj. The temperature control unit C sends the four data of BTON status, ambient temperature T0, battery pack temperature Tobj, and button battery power Avq to the AC management unit A through radio frequency wireless communication.

[0071] In this embodiment, an electric bicycle charging protection system and its control method add three modules on the basis of the original charger, namely, an AC management unit, a DC management unit, and a temperature control unit, which realize functions such as automatic protection of the charger, automatic shutdown of the charging time, and temperature protection, and can effectively avoid safety risk problems caused by incorrect charging, abnormal charging, too high temperature of the battery pack, short circuit, overload, etc. Among them, in the AC management unit, a touch screen and a Bluetooth connection to the mobile phone APP are set up, which is convenient for users to customize the system parameters of the charging control on the touch screen or the mobile phone APP side, and thus can meet the charging protection control of various battery packs of different brands and models, with strong versatility and greater flexibility. In the temperature control unit, a proximity switch that is completely attached to the battery pack is set to detect whether the module is in place, ensuring the accuracy of the sensor detection data in the temperature control unit, and allowing charging only when the proximity switch is in the closed state, ensuring the reliability of the charging protection control. A static switch for controlling the on / off of the charger power supply is set in the AC management unit. When charging is not allowed, the power connection is directly disconnected, completely stopping the charging, which is more reliable and safe.

[0072] The above are only some embodiments of the present invention. For those of ordinary skill in the art, without departing from the inventive concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention.

Claims

1. An electric bicycle charging protection system, which includes a charger and a DC management unit B, is characterized in that: It also includes an AC management unit A and a temperature control unit C arranged on the battery pack; one end of the AC management unit A is electrically connected to the mains power supply and the other end is electrically connected to the input end of the charger; One end of the DC management unit B is electrically connected to the output end of the charger and the other end is electrically connected to the charging socket of the electric bicycle; The AC management unit A includes a microprocessor and its peripheral circuit AC-MU, an AC voltage processing circuit AC-U electrically connected to the microprocessor and its peripheral circuit AC-MU, a radio frequency communication module RF1, a Bluetooth communication module BT, a static switch DK, and an AC current processing circuit AC-I, a voltage transmitter TV, a plug JP1, and a socket JP2; one end of the plug JP1 is connected to the mains power supply and the other end is connected to the socket JP2, and the voltage transmitter TV collects the mains AC voltage Uac accessed by the plug JP1 and transmits it to the AC voltage processing circuit AC-U; the static switch DK is arranged on the connection line between the plug JP1 and the socket JP2 and its on-off state is controlled by the microprocessor and its peripheral circuit AC-MU; on the connection line between the plug JP1 and the socket JP2, there are also arranged a current transformer CT1 for detecting the input mains AC current Iac and a current transformer CT2 for detecting the loop leakage current Ild, and the detection data of the current transformer CT1 and the current transformer CT2 are uploaded to the AC current processing circuit AC-I; The socket JP2 is electrically connected to the input end of the charger; The DC management unit B includes a microprocessor and its peripheral circuit DC-MU, a DC voltage measurement circuit DC-U, a DC current measurement circuit DC-I, a radio frequency communication module RF2, a plug JP3, and a socket JP4 electrically connected to the microprocessor and its peripheral circuit DC-MU; The socket JP4 is electrically connected to the charging socket of the electric bicycle; The DC voltage measurement circuit DC-U collects the charging DC voltage Udc output by the charger, and the DC current measurement circuit DC-I collects the charging current Idc output by the charger and transmits them to the microprocessor and its peripheral circuit DC-MU; a DC relay is arranged on the connection line between the plug JP3 and the socket JP4, and the DC relay is controlled by the microprocessor and its peripheral circuit DC-MU to realize on-off switching; The temperature control unit C includes a microprocessor and its peripheral circuit WK-MU, an ambient temperature sensor T1, an infrared thermopile sensor T2, a capacitive proximity switch, and a radio frequency communication module RF3 electrically connected to the microprocessor and its peripheral circuit WK-MU. The temperature control unit C is adsorbed on the battery pack of the electric bicycle through a strong suction cup as a whole, and the capacitive proximity switch is arranged on the side close to the battery surface; the infrared thermopile sensor T2 collects the battery pack temperature and transmits it to the microprocessor and its peripheral circuit WK-MU.

2. The electric bicycle charging protection system according to claim 1, characterized in that: The AC management unit A also includes a power supply circuit PW1 electrically connected to the microprocessor and its peripheral circuit AC-MU.

3. The electric bicycle charging protection system according to claim 1, characterized in that: The AC management unit A also includes a touch screen HMI electrically connected to the microprocessor and its peripheral circuit AC-MU, which is used for users to set system parameters.

4. The electric bicycle charging protection system according to claim 1, characterized in that: The DC management unit B further includes a wide-input DC power supply module PW2 electrically connected to the microprocessor and the peripheral circuit DC-MU.

5. The electric bicycle charging protection system according to claim 1, characterized in that: The temperature control unit C further includes a button battery for powering the microprocessor and the peripheral circuit WK-MU, a DC power supply circuit provided between the button battery and the microprocessor and the peripheral circuit WK-MU, and a power detection circuit for detecting the power of the button battery. The power detection circuit collects the power of the button battery and transmits it to the microprocessor and the peripheral circuit WK-MU.

6. A control method for the electric bicycle charging protection system according to claim 1, characterized in that: It includes: S1) Reading the system set parameters; the system set parameters include the minimum allowable voltage Uacmin of the charger, the maximum allowable voltage Uacmax of the charger, the rated power S of the charger, the leakage protection current Ildset of the charger, the maximum charging current Idcmax of the battery, the floating charge voltage value Udco at -30°C, the floating charge voltage value Udcp at 50°C, the maximum allowable charging time Tcmax, the minimum allowable charging ambient temperature T0min, the maximum allowable charging ambient temperature T0max, and the battery temperature protection value Tobjmax; S2) Collecting the system measurement parameters: obtaining the measured values of the mains voltage Uac, the charger AC terminal current Iac, and the charger AC terminal leakage value Ild through the AC management unit A; obtaining the charger DC current Idc, the charging DC voltage Udc-c, and the battery floating voltage Udc-k by reading the data of the DC management unit B through radio frequency communication; obtaining the ambient temperature measurement value T0, the battery temperature measurement value Tobj, and the adsorption state BTON of the capacitive proximity switch by reading the data of the temperature control unit C through radio frequency communication; S3) Calculating the calculated parameters: The charger current rating Ie = S / 220V, The charging overload current Iod = 1.2Ie, The charging overcurrent Ioc = 3Ie, The battery floating charge voltage value Udcz = Udco + Kp × T0, where Kp = (Udcp - Udco) / 80; S4) Judging whether the charging allowable conditions (1), (2), and (3) are all satisfied. If satisfied, execute the next step. If not satisfied, set the charging flag FLAG to 3 and execute step S8); the charging allowable condition (1) is Uacmin < Uac < Uacmax; the charging allowable condition (2) is T0min < T0 < T0max; the charging allowable condition (3) is that BTON is in the suction state; S5) Judging whether the charging non-allowable conditions (4), (5), (6), (7), and (8) are satisfied. If one of the conditions is satisfied, set FLAG to 4 to indicate that a charging protection action is to be performed and execute step S8). If none of the five conditions are satisfied, execute the next step; the charging non-allowable condition (4) is Ild > Ildset; the charging non-allowable condition (5) is Iac > Iod; the charging non-allowable condition (6) is Iac > Ioc; the charging non-allowable condition (7) is Idc > Idcmax; the charging non-allowable condition (8) is Tobj > Tobjmax; S6) Determine whether both of the charging permission conditions (9) and (10) are satisfied. If so, it indicates normal charging, and the charging time Tch is counted. Otherwise, set FLAG to 5 to indicate abnormal charging, and execute step S8); the charging permission condition (9) is Udc-c < Udcz + 3; the charging permission condition (10) is Udc-k < 1.2 × Udcz; S7) Determine whether the charging time Tch has reached the maximum charging time Tcmax. If so, set FLAG to 2 to indicate that charging is complete, and execute the next step; otherwise, return to step S2); S8) Disconnect the static switch DK to turn off charging.

7. The control method of the electric bicycle charging protection system according to claim 6, characterized in that: The control process of the DC management unit B includes: controlling the JK signal to close the DC relay to obtain the charging DC voltage Udc-c and the charger DC current Idc; controlling the JK signal to open the DC relay to measure the floating voltage Udc-k of the battery when not charging. The DC management unit B sends the three data of Udc-c, Udc-k, and Idc to the AC management unit A through radio frequency wireless communication.

8. The control method of the electric bicycle charging protection system according to claim 6, characterized in that: The control process of the temperature control unit C includes: detecting the BTON status of the capacitive proximity switch. If the temperature control unit C has been adsorbed on the battery pack, the status of BTON is 1, otherwise the status is 0; reading the data of the ambient temperature sensor T1 to obtain the ambient temperature T0; reading the data of the infrared thermopile sensor T2 to obtain the measured battery temperature Tobj; the temperature control unit C sends the BTON status, the ambient temperature T0, and the measured battery temperature Tobj to the AC management unit A through radio frequency wireless communication.

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