TWI775291B - Bidirectional ac charging divece and method of operating the same - Google Patents

Abstract

A bidirectional AC charging device is coupled to a power grid and an electric vehicle, and includes a power transmission path, a switch, a first controller, a communication unit and a second controller. One end of the power transmission path is coupled to the grid through the first connection port, and the other end is coupled to the electric vehicle through the second connection port. The switch is configured on the power transmission path, the communication unit is coupled to the second connection port, and the first controller is coupled to the power transmission path, the switch, the second controller and the communication unit. When the second controller receives a power demand request and informs the first controller, the first controller switches from a first signal to a second signal to communicate with the vehicle and turns off the switch, and when the first controller receives a ready-to-feed notification from the vehicle, the controller turns on the switch.

Description

Bidirectional AC charging device and operation method thereof

The present invention relates to an AC charging device, in particular to an AC charging device capable of bidirectional power supply and an operation method thereof.

In recent years, due to the rising awareness of environmental protection, government agencies have actively implemented energy-saving and carbon-reduction policies, and the electric vehicle industry, which can greatly reduce air pollution, has also flourished. With the increasing popularity of electric vehicle applications, the charging technology of electric vehicles has also received increasing attention. FIG. 1 is a circuit block diagram of a conventional AC charging device. The traditional charging method for electric vehicles using AC charging is to couple the mains 2 through the AC charging device 1 ′, and use a charging gun to physically couple the electric vehicle 3 to charge the electric vehicle 3 . Electric vehicle 3 is charged. The conventional AC charging device 1 ′ can usually only provide the mains power P1 through the mains 2 to charge the electric vehicle 3 unidirectionally. During the charging process, the controller 16 ′ uses the communication unit 14 to communicate with the electric vehicle 3 and controls the switch 20 On to provide a power transfer path for charging. However, due to the increasing demand for electricity year by year, power companies are faced with the pressure to balance the supply and demand of the power grid, coupled with the diversification of energy applications such as smart grids, renewable energy, and distributed energy, so that the supply and demand of electricity is no longer limited to the power generation side. One-way supply to the load side, so the power company must make more dynamic and flexible power dispatching in a timely manner according to the actual load demand, power cost and its cost performance. Therefore, the traditional structure in which the mains 2 charges the electric vehicle 3 in one direction can no longer meet the requirements of the above-mentioned flexible application of the power system.

Therefore, how to design a bidirectional AC charging device and its operation method to provide a bidirectional power supply solution between mains and AC charging type electric vehicles according to the actual power dispatching requirements of the power system is the author of this case. A major subject for research.

In order to solve the above problems, the present invention provides a bidirectional AC charging device, which is coupled to the commercial power and the electric vehicle, and includes: a power transmission path, one end of which is coupled to the commercial power through the first connection port, and the other end is coupled to the second connection port. Electric vehicle. The switch is arranged on the power transmission path. The first controller is coupled to the power transmission path and the switch. The second controller is coupled to the first controller and receives a power demand request. The communication unit is coupled to the first controller and the second connection port. When the second controller receives a power demand request, it provides a first notification to the first controller, and the first controller switches from the first signal to the second signal through the communication unit according to the first notification and communicates with the electric vehicle and controls the switch It is not conductive, and when the first controller receives the notification of allowing power feeding provided by the electric vehicle, the control switch is turned on; when the second controller receives the demand suspension request and correspondingly provides the second notification to the first controller, Or when the first controller receives a notice of suspending the feeding, the first controller controls the switch to be turned off and communicates with the electric vehicle after switching from the second signal to the first signal through the communication unit.

In order to solve the above problem, the present invention provides an operation method of a bidirectional AC charging device, comprising the following steps: (a) receiving a power demand request through the second controller. (b) When the second controller receives the power demand request, the first controller is notified, so that the first controller can communicate with the electric vehicle after switching from the first signal to the second signal through the communication unit and control the power transmission path to be non-conductive . (c) When the first controller receives the notification of permission to feed power, the power transmission path is controlled to be turned on. (d) When the second controller receives a demand suspension request and notifies the first controller, or when the first controller receives a notice of feeding suspension, the first controller switches from the second signal to the first signal through the communication unit Then communicate with the electric vehicle and control the power transmission path to be non-conductive.

The main purpose and effect of the present invention is that the first controller automatically responds accordingly according to whether the second controller has received a power demand request and a demand suspension request, and whether the first controller has received a power feeding permission notice or a power feeding suspension notice. The switch is controlled to be turned on or off, so as to provide a corresponding power supply direction according to the demand of the commercial power and the state of the electric vehicle, so that the AC charging device of the present invention can achieve the effect of bidirectional power supply.

In order to further understand the technology, means and effect adopted by the present invention to achieve the predetermined purpose, please refer to the following detailed description and accompanying drawings of the present invention. For specific understanding, however, the accompanying drawings are only provided for reference and description, and are not intended to limit the present invention.

Hereby, the technical content and detailed description of the present invention are described as follows in conjunction with the drawings:

Please refer to FIG. 2 , which is a circuit block diagram of the bidirectional AC charging device of the present invention. The two-way AC charging device 1 is coupled to the mains 2, and is used to provide the electric vehicle 3 to be charged by the mains 2 according to the requirements of the electric vehicle 3 and the mains 2 when the electric vehicle 3 is coupled to the two-way AC charging device 1, Or a power transmission path where the electric vehicle 3 feeds the commercial power 2 . The electric vehicle 3 may be an electric vehicle, an electric vehicle, or the like, which is driven by electricity. The bidirectional AC charging device 1 includes a power transmission path 12 , a switch 20 , a communication unit 14 , a second controller 16B and a first controller 16A; the switch 20 is disposed on the power transmission path 12 , and controls the conduction and non-conduction of the switch 20 The effect of turning on or off the power transmission path 12 can be achieved. Moreover, one end of the power transmission path 12 is coupled to the mains 2 through the power interface of the first connection port 1A, and the other end is coupled to the electric vehicle 3 through the power interface of the second connection port 1B. Such a coupling relationship enables the power transmission path 12 to have a mains power transmission direction T1 in which power (charging) is transmitted from the first connection port 1A to the second connection port 1B, and power is transmitted from the second connection port 1B to the first connection port 1A. The feeding power transmission direction T2 of (feeding).

The communication unit 14 is coupled to the first controller 16A, and is coupled to the electric vehicle 3 through the communication interface of the second connection port 1B. The communication unit 14 is used to provide a communication channel for information exchange between the first controller 16A and the electric vehicle 3, so as to know the current status and power demand of each other. After the electric vehicle 3 is physically coupled to the two-way AC charging device 1 , the first controller 16A and the electric vehicle 3 know each other's current status and power demand through the communication unit 14 , so that the first controller 16A can communicate with the electric vehicle 3 according to its current status and power demand. The decision after the vehicle 3 handshakes the communication controls the two-way AC charging device 1 accordingly (provides a charging or feeding path). The second controller 16B is connected to the mains management system 2A and the first controller 16A, and the second controller 16B may be a grid specification controller. The second controller 16B is used for communicating with the mains management system 2A to obtain relevant information of the mains, such as but not limited to: the voltage, current, frequency and other states of the mains and the electricity demand of the mains. When the mains management system 2A provides a power demand request RP or a demand suspension request to the second controller 16B according to the current mains peak load, supply and demand balance, or the need to maintain grid quality, the second controller 16B provides the second controller 16B according to the power demand request RP. A notification is sent to the first controller 16A, or a second notification is provided to the first controller 16A according to the demand suspension request, and the first controller 16A determines the switching of the switch 20 according to the received notification type.

Specifically, the switching of the switch 20 is controlled according to the demand on the mains side or the electric vehicle side, and the power flow is caused by the system behavior of charging from the mains 2 to the electric vehicle 3 or feeding the electric vehicle 3 to the mains 2, roughly Available operation modes are distinguished for ease of description. According to an embodiment of the present invention, the operation mode includes a charging mode in which the switch 20 is turned on to provide the mains power P1 from the first connection port 1A to the second connection port 1B through the power transmission path 12 (ie, the mains power transmission direction T1 ). The operation mode also includes a feeding mode in which the switch 20 is turned on so that the feeding power P2 is supplied from the second connecting port 1B to the first connecting port 1A through the power transmission path 12 (ie, the feeding power transmission direction T2 ). In addition, the operation mode further includes non-conducting the switch 20 to interrupt the power transmission path 12, resulting in a standby mode with no current power transmission. In addition to the aforementioned notification type, the first controller 16A also selects to operate in the power feeding mode, the charging mode or the standby mode according to the resolution after it has held communication with the electric vehicle 3 .

Further, after the electric vehicle 3 is physically coupled to the second connection port 1B, the first controller 16A presets to transmit the first signal Sc1 to the electric vehicle 3 coupled to the second connection port 1B through the communication unit 14. The first signal Sc1 is a pulse width modulated (PWM) signal with a frequency of about 1 kHz according to the standard of electric vehicle conduction charging specification (IEC 61851). After the electric vehicle 3 is physically coupled to the second connection port 1B, in addition to the default transmission of the first signal Sc1 with the first controller 16A, if the second controller 16B receives the power demand request RP from the mains management system, And after providing the first notification to the first controller 16A, the communication between the first controller 16A and the electric vehicle 3 will be changed to a second signal Sc2 different from the first signal Sc1, such as but not limited to pulse, packet or a signal whose frequency is different from that of the first signal Sc1. The first controller 16A transmits the relevant information of the power demand request RP (such as but not limited to: the power demand power of the current mains, the actual power or frequency correction demand value of the current mains compensation, etc.) through the second signal Sc2 and the electric vehicle. 3. The handshake of the information is performed. After the information handshake of the power demand request RP is completed, the first controller 16A sets the operation mode to the standby mode, and the control switch 20 is turned off to avoid any current power transmission behavior. During the period of communication using the second signal Sc2, if the electric vehicle 3 determines that its own state and its configured battery state are not abnormal and the power is sufficient to meet the demand content of the power demand request RP, it provides a notification of allowing power feeding to the first controller 16A, representing that the electric vehicle 3 is allowed to feed its own stored power back to the mains 2 .

The aforementioned power feeding permission notification is provided to the first controller 16A through the communication interface and the communication unit 14 of the second connection port 1B, so that the first controller 16A determines that the electric vehicle 3 is allowed to feed the stored power back to the mains 2 according to the signal. , and set the operation mode to feed mode. Since the first controller 16A communicates with the electric vehicle 3 in the charging mode with a PWM signal of approximately 1 kHz, it is easier to use a signal whose frequency is different from the first signal Sc1 in the communication application in the feeding mode. For example, according to an embodiment of the present invention, it is preferable that the second signal Sc2 is a signal whose frequency is higher than that of the first signal Sc1. Among them, in order to be clearly distinguishable from the 1kHz signal and easy to implement, the second signal Sc2 is preferably a 10kHz signal. On the other hand, after the electric vehicle 3 is physically coupled to the second connection port 1B, if the first controller 16A does not receive the power demand request RP from the mains management system 2A, it means that it does not need to operate in the feeding mode. When the electric vehicle 3 needs to be charged and transmits a charge permission notification to the first controller 16A, the first controller 16A determines that the electric vehicle 3 needs to be charged and sets the operation mode to the charging mode.

Please refer to FIG. 3 , which is a block diagram of the mode switching of the bidirectional AC charging device of the present invention, and refer to FIG. 2 in combination. According to an embodiment of the present invention, the switching between the above-mentioned various modes, such as switching from the charging mode CM to the feeding mode BM, or between the feeding mode BM and the charging mode CM, there is a standby mode SM, in the standby mode In the mode SM, the first controller 16A controls the switch 20 to be non-conductive, so that the power transmission path 12 is interrupted, so as to prevent improper current flow between the mode switching, which may cause the bidirectional AC charging device 1, the electric vehicle 3 or the personnel. damage. For example, when operating in the charging mode CM, the first controller 16A communicates with the electric vehicle 3 via the first signal Sc1. If the power demand request RP from the mains management system 2A is received, the second controller 16B provides The first notification N1 is sent to the first controller 16A, and the first controller 16A will first stop the communication of the first signal Sc1, and use the second signal Sc2 to communicate with the electric vehicle 3, so as to communicate the information related to the power demand request RP with the electric vehicle 3. Vehicle 3 handshakes the message. After the two parties complete the handshake of the information related to the power demand request RP, the first controller 12 switches the operation mode to the standby mode SM, and simultaneously controls the switch 20 to be turned off to interrupt the power transmission path 12 . After confirming that the power transmission path 12 is interrupted, the first controller 16A switches to the power feeding mode BM after the electric vehicle 3 provides a power feeding permission notification NB (in the format of the second signal Sc2 ), and controls the switch 20 to be turned on, so that The feeding power P2 of the electric vehicle 3 is transmitted through the second connection port 1B to the first connection port 1A through the power transmission path 12 to be supplied to the commercial power 2 .

Conversely, when operating in the feeding mode BM, when the first controller 16A communicates with the electric vehicle 3 via the second signal Sc2, if a demand suspension request RS is received from the mains management system 2A (the second controller 16B provides a second notification N2 to the first controller 16A), or receives a feed-stop notification from the electric vehicle 3 due to internal events (such as but not limited to electric vehicle system failure, battery failure or low battery power) NS (in the format of the second signal Sc2), the first controller 16A will first stop the communication of the second signal Sc2, and switch the operation mode to the standby mode SM, and control the switch 20 to be non-conductive to interrupt the power transmission path 12. When After confirming that the power transmission path 12 is interrupted, the first controller 16A uses the first signal Sc1 to communicate with the electric vehicle 3 and waits for the electric vehicle 3 to provide a charge permission notification NA (in the format of the first signal Sc1 ). Switching to the charging mode CM, the control switch 20 is turned on, so that the mains power P1 of the mains 2 is transmitted from the first connection port 1A to the second connection port 1B through the power transmission path 12 to be supplied to the electric vehicle 3 .

In this way, the first controller 16A can automatically switch to the electric vehicle 3 through the judging method of receiving different power demand requests from the mains management system 2A and communicating with the electric vehicle 3 through different types of signals. The feeding mode BM, the charging mode CM or the standby mode SM are no longer like the prior art in FIG. 1 , but only have a control mode of unidirectional charging. In this way, a corresponding power supply direction can be provided according to the demand of the electric vehicle 3, so that the AC charging device of the present invention can achieve the effect of bidirectional power supply.

Referring back to FIG. 2 , the bidirectional AC charging device 1 further includes a detection circuit 18 and a switch 20 , and the detection circuit 18 and the switch 20 are coupled to the power transmission path 12 and the first controller 16A. The detection circuit 18 detects the power of the power transmission path 12 to generate a power information signal and a power information signal Sp, and the first controller 16A determines whether to control the switch 20 to be turned on or off to turn on or off the power transmission according to the power information signal Sp Path 12. Specifically, the detection circuit 18 includes a plurality of detection units, which may include a first voltage detection unit 182, a current detection unit 184, a frequency detection unit 186, a residual current detection unit 188 and a second voltage detection unit The unit 190 is a detection unit for detecting the power parameters on the power transmission path 12, and the detection units 182-190 are respectively coupled to the first controller 16A.

The first voltage detection unit 182 detects the voltage of the first path from the first connection port 1A to the switch 20 to generate a first voltage signal Sv1, and the second voltage detection unit 190 detects the voltage of the switch 20 to the second connection port 1B. The voltage of the second path generates a second voltage signal Sv2. When the switch 20 is not turned on, the aforementioned first voltage signal Sv1 corresponds to the voltage on the mains side, and the second voltage signal Sv2 corresponds to the voltage on the electric vehicle side. The current detection unit 184 detects the current of the power transmission path 12 to generate a current signal Si, and the frequency detection unit 186 detects the frequency of the voltage and current of the power transmission path 12 to generate a frequency signal Sf; the residual current detection unit 188 The residual current of the power transmission path 12 is detected to provide a residual current signal Sir. The power information signal Sp may include at least a first voltage signal Sv1, a second voltage signal Sv2, a current signal Si, a frequency signal Sf and a residual current signal Sir, and the first controller 16A determines whether to control the switch 20 to be turned on or not according to the above signals. The power transmission path 12 is turned on. Further, the first controller 16A can determine whether the power on the power transmission path 12 has over-voltage/under-voltage (OV/UV) according to the first voltage signal Sv1 , the second voltage signal Sv2 , the current signal Si and the frequency signal Sf , over current (OC), over frequency/under frequency (OF/UF), and the residual current signal Sir can determine whether there is a leakage current between the power transmission path 12 and the ground terminal N. When the above situation does not occur, the first controller 16A controls the switch 20 to be turned on, so that the power transmission path 12 is turned on. On the contrary, the control switch 20 is turned off, so that the power transmission path 12 is turned off. The switch 20 may be a switch with two transistors connected in series or a relay, etc., and a switch element that can be turned on/off in both directions.

Referring back to FIG. 2 , the bidirectional AC charging device 1 further includes an auxiliary power circuit 30 , and the auxiliary power circuit 30 is coupled to the system internal loads of the bidirectional AC charging device 1 , such as but not limited to the first controller 16A, the communication unit 14 , the switch 20 , and other peripheral circuits or electronic components that require auxiliary power to operate, and the auxiliary power circuit 30 includes a first conversion circuit 30A and a second conversion circuit 30B. The first conversion circuit 30A is coupled to two of the phases on the power transmission path 12 (applicable to a three-phase system or a single-phase system), and the specific coupling position is preferably closer to the first connection port 1A. The first conversion circuit 30A may be a conventional AC-DC conversion circuit, such as, but not limited to, a flyback conversion circuit, a forward conversion circuit, and the like. The first conversion circuit 30A converts the power on the power transmission path 12 into the auxiliary power Vcc required for the operation of the internal load of the system, wherein the auxiliary power Vcc may be +15V, +12V, +5V and/or +3V, but not limited thereto . The second conversion circuit 30B is coupled to two of the phases on the power transmission path 12 (applicable to a three-phase system or a single-phase system), and the specific coupling position is preferably closer to the second connection port 1B. The second conversion circuit 30B can also be a conventional AC-DC conversion circuit, which converts the power on the power transmission path 12 into the auxiliary power Vcc required for the operation of the internal load of the system, and the output end of the second conversion circuit 30B is connected to the first The output terminals of the conversion circuit 30A are connected in parallel.

Specifically, one of the features of the bidirectional AC charging device 1 of the present invention is that the auxiliary power Vcc required for the operation of the internal load of the system can be generated by the first conversion circuit 30A and/or the second conversion circuit in different operation modes. 30B supply. When the first controller 16A operates in the charging mode CM, since the switch 20 is turned on, the mains power P1 can be converted by the first conversion circuit 30A or the second conversion circuit 30A into the auxiliary power Vcc required for the operation of the internal load of the system, so that the first The controller 16A can stably control the charging mode CM for the entire bidirectional AC charging device 1 . Similarly, in the feeding mode BM, the feeding power P2 can be converted by the first converting circuit 30A or the second converting circuit 30A into the auxiliary power Vcc required for the operation of the internal load of the system. However, when the first controller 16A operates in the standby mode SM, the switch 20 is not turned on. At this time, only the mains 2 or one side of the electric vehicle 3 can provide power. With the assistance of the double conversion circuit in the present invention The power supply circuit 30 is designed so that no matter which side can provide power, the corresponding conversion circuit can convert it into the auxiliary power Vcc required for the operation of the internal load of the system. Therefore, assuming that there is only the first converted power 30A, and when the mains 2 fails and the first controller 16A operates in the feeding mode, or when the standby mode SM wants to enter the feeding mode BM, but the switch 20 is not turned on, the first controller 16A operates in the feeding mode. A controller 16A cannot obtain the auxiliary power Vcc required for operation, which causes the bidirectional AC charging device 1 to fail (and vice versa). Therefore, by adding the second conversion circuit 30B, the first controller 16A can successfully obtain the auxiliary power Vcc required for operation through the other side no matter which side loses the power.

Please refer to FIG. 4A for a schematic block diagram of the controller of the present invention when operating in the charging mode, and FIG. 4B for a schematic block diagram of the controller of the present invention operating in the feeding mode. Please refer to FIGS. 2 to 3 in conjunction. In FIG. 4A , after the electric vehicle 3 is physically coupled to the second connection port 1B, the first controller 16A is preset to communicate with the electric vehicle 3 coupled to the second connection port 1B through the communication unit 14 by the first signal Sc1 , and the first controller 16A operates in the charging mode CM after obtaining the charging permission notification provided by the electric vehicle 3 through the handshake of the message. Then, the first controller 16A controls the switch 20 of the bidirectional AC charging device 1 to be turned on, so that the mains power P1 in the mains power transmission direction T1 provided by the mains power 2 is transmitted by the first connection port 1A, the switch 20 and the second connection port 1B to Electric Vehicle 3.

In FIG. 4B , after the electric vehicle 3 is physically coupled to the second connection port 1B, the controller 16A presets to communicate with the electric vehicle 3 coupled to the second connection port 1B through the communication unit 14 with the first signal Sc1 , The second controller 16B is coupled to the mains management system 2A to obtain relevant information of the mains 2 through the mains management system 2A, such as but not limited to the current voltage, current, frequency status, and power demand of the mains 2 . If the second controller 16B receives the power demand request RP from the mains management system 2A, and provides the first notification to the N1 first controller 16A according to the power demand request RP, the first controller 16A will stop communicating with the electric vehicle 3 transmits the first signal Sc1 to each other, and then communicates with the electric vehicle 3 through the second signal Sc2, and handshakes the information related to the power demand request RP with the electric vehicle 3. After the handshake of the information related to the power demand request RP is completed, the first controller operates in the standby mode SM, and the control switch 20 is turned off to interrupt the power transmission path 12 . If the first controller 16A receives the power feeding permission notification NB provided by the electric vehicle 3 through the communication unit 14, the first controller 16A switches to operate in the power feeding mode BM. Wherein, the power feeding permission notification NB and the power feeding suspension notification NS shown in FIG. 3 are notified in the format of the second signal Sc2. Then, the first controller 16A determines the optimal turn-on time point of the switch 20 according to the current mains information provided by the second controller 16B; or the first controller 16A provides the current mains information to the electric vehicle, and the electric vehicle The first controller 16A controls the switch 20 to turn on after judging the voltage and phase of the feed according to the mains information, and outputs the feed power and notifies the first controller 16A, so as to facilitate the transmission direction T2 of the feed power provided by the electric vehicle 3 The feeding power P2 is transmitted to the mains 2 through the second connection port 1B, the switch 20 and the first connection port 1A. Wherein, if the first signal Sc1 and the second signal Sc2 are different types of signals, they can be transmitted using different signal transmission lines (as shown in FIG. 4B ); when the first signal Sc1 and the second signal Sc2 are of the same type When the signal (for example, both are PWM signals, the difference is only in the frequency), the same signal transmission line can be used for transmission, and the application of the transmission line can be adjusted correspondingly according to the actual needs.

Please refer to FIG. 5A for a flow chart of the operation method of the mode setting of the bidirectional AC charging device of the present invention, and refer to FIGS. 2 to 4B in combination. The operation method of the bidirectional AC charging device 1 includes receiving a power demand request through the second controller (S100). The second controller 16B is connected to the mains management system 2A and the first controller 16A, and the second controller 16B is used to communicate with the mains management system 2A to obtain relevant information of mains, such as but not limited to: mains status and mains power demand . Then, when the second controller receives the power demand request from the mains management system, it notifies the first controller, so that the first controller switches from the first signal to the second signal through the communication unit and communicates with the electric vehicle and controls the power The transmission path is turned off (S120). When the mains management system 2A provides the power demand request RP to the second controller 16B according to the current demand for the balance of mains power supply and demand, the second controller 16B provides a first notification to the first controller 16A according to the power demand request RP. After the first controller 16A receives the first notification, the communication between the first controller 16A and the electric vehicle 3 will use a second signal Sc2 different from the first signal Sc1, such as, but not limited to, pulse, packet or A signal whose frequency is different from that of the first signal Sc1. After the first controller 16A handshakes the relevant information of the power demand request RP with the electric vehicle, the first controller 16A controls the switch 12 on the power transmission path 12 to be turned off to interrupt the power transmission path 12 .

Then, when the first controller receives a notification of allowing power feeding provided by the electric vehicle, it controls the power transmission path to be turned on (S140). During the period of communication using the second signal Sc2, if the electric vehicle 3 determines that its own state and its configured battery state are not abnormal and the power is sufficient to allow power feeding, it provides a power feeding permission notification to the first controller 16A, representing the electric power Vehicle 3 allows to feed back the mains 2 with its own stored power. The power feeding permission notification is provided to the first controller 16A through the communication interface and the communication unit 14 of the second connection port 1B, so that the first controller 16A determines that the electric vehicle 3 is allowed to feed the stored power back to the mains 2 according to the signal. And the operation mode is set to the feeding mode, and the switch 20 on the power transmission path 12 is turned on to turn on the power transmission path 20 to provide a path for power to be transmitted from the electric vehicle to the commercial power.

Then, in the feeding mode, the second controller notifies the first controller when the second controller receives a demand suspension request from the mains management system, so that the first controller switches from the second signal to the first signal through the communication unit and communicates with the electric load with communication, and the control power transmission path is non-conductive (S160); or in the power feeding mode, when the first controller receives a notice of suspension of power feeding from the electric vehicle, the communication unit switches from the second signal to the second signal A signal is then communicated with the electric vehicle, and the power transmission path is controlled to be turned off (S180). In step ( S140 ), when operating in the power feeding mode BM, when the first controller 16A communicates with the electric vehicle 3 via the second signal Sc2 , if the second controller 16B receives a signal from the mains management system 2A through the second controller 16B When the demand suspension request RS, or the first controller 16A receives a feed suspension notification NS from the electric vehicle 3, the first controller 16A switches from the second signal Sc2 to the first signal Sc1 to communicate with the electric vehicle 3, Then, the standby mode SM is entered, and the switch 20 on the power transmission path 12 is controlled to be non-conductive, so as to cut off the power transmission path 12 .

Finally, in the standby mode, when the first controller receives a charging permission notification provided by the electric vehicle, it operates in a charging mode in which the commercial power is provided to the electric vehicle through the power transmission path (S200). After steps ( S160 ) and ( S180 ), when the first controller 16A enters the standby mode and confirms that the power transmission path 12 is interrupted, it continues to communicate with the electric vehicle 3 with the first signal Sc1 and waits for the electric vehicle 3 to provide After the charging permission is notified to NA, it is switched to the charging mode CM, and the control switch 20 is turned on, so that the mains power P1 of the mains 2 is transmitted from the first connection port 1A to the second connection port 1B through the power transmission path 12 and supplied to the electric vehicle 3 .

Please refer to FIG. 5B for a flowchart of the protection mechanism method of the bidirectional AC charging device of the present invention, and refer to FIGS. 2 to 5A in combination. Steps ( S100 ) to ( S200 ) include a protection mechanism for the bidirectional AC charging device 1 , and the steps include: detecting the power of the power transmission path to generate a power information signal ( S300 ). The detection circuit 18 includes a plurality of detection units, which may include a first voltage detection unit 182, a current detection unit 184, a frequency detection unit 186, a residual current detection unit 188, a second voltage detection unit 190, etc. A detection unit for detecting power parameters on the power transmission path 12 . The detection circuit 18 detects the power of the power transmission path 12 to generate a power information signal Sp. The power information signal Sp may at least include a first voltage signal Sv1, a second voltage signal Sv2, a current signal Si, a frequency signal Sf and a residual current signal Sir. Then, the first controller controls the power transmission path to be turned on or off according to the power information signal (S320). The first controller 16A can determine whether the power on the power transmission path 12 has overvoltage/undervoltage (OV/UV), overcurrent ( OC), over-frequency/under-frequency (OF/UF) conditions, and the residual current signal Sir can determine whether there is a leakage current condition between the power transmission path 12 and the ground terminal N. When the above situation does not occur, the first controller 16A controls the switch 20 to be turned on, so that the power transmission path 12 is turned on. On the contrary, the control switch 20 is turned off, so that the power transmission path 12 is turned off.

However, the above descriptions are only the detailed descriptions and drawings of the preferred embodiments of the present invention, but the features of the present invention are not limited thereto, and are not intended to limit the present invention. The scope of the patent shall prevail, and all embodiments that are consistent with the spirit of the scope of the patent application of the present invention and similar variations thereof shall be included in the scope of the present invention. Anyone who is familiar with the art in the field of the present invention can easily think Changes or modifications can be covered by the following patent scope of the present case.

1’…Charging unit

1…Bidirectional AC charging device

1A…first port

1B…Second port

12…Power Transmission Path

14…communication unit

16’ …controller

16A…First Controller

16B…Second Controller

18…Detection line

182...the first voltage detection unit

184…Current detection unit

186…Frequency detection unit

188…Residual current detection unit

190...Second voltage detection unit

20…Switch

30…Auxiliary power circuit

30A...first conversion circuit

30B...Second conversion circuit

2…Mains

2A…Mains power management system

3…Electric Vehicles

P1…Mains Electricity

T1…Direction of mains power transmission

P2…feeding power

T2…feeding power transmission direction

Vcc...auxiliary power

Sc1…First Signal

Sc2…Second signal

N1…First Notice

N2…Second Notice

NB…Allow Feed Notifications

NS…Notice of Suspended Feeding

NA…Allow charging notifications

RP…Power Demand Request

RS...demand abort request

CM…Charging Mode

SM…standby mode

BM…feed mode

Sp…Power Information Signal

Sv1…the first voltage signal

Sv2…Second voltage signal

Si...current signal

Sf…frequency signal

Sir...residual current signal

S100~S320...steps

FIG. 1 is a circuit block diagram of a conventional charging device;

2 is a circuit block diagram of the bidirectional AC charging device of the present invention;

3 is a block diagram of mode switching of the bidirectional AC charging device of the present invention;

4A is a schematic block diagram of the controller of the present invention operating in a charging mode;

4B is a schematic block diagram of the controller of the present invention operating in a feeding mode;

5A is a flow chart of the operation method of the mode setting of the bidirectional AC charging device of the present invention; and

5B is a flow chart of the protection mechanism method of the bidirectional AC charging device of the present invention.

Sc1…First Signal Sc2…Second signal N1…First Notice N2…Second Notice NB…Allow Feed Notifications NS…Notice of Suspended Feeding NA…Allow charging notifications RP…Power Demand Request RS...demand abort request CM…Charging Mode SM…standby mode BM…feed mode

Claims (13)

A bidirectional AC charging device is coupled to a mains and an electric vehicle, and includes: a power transmission path, one end is coupled to the mains through a first connection port, and the other end is coupled to the electric vehicle through a second connection port ; a switch, configured on the power transmission path; a first controller, coupled to the power transmission path and the switch; a second controller, coupled to the first controller, and received from a commercial power management system a power demand request; and a communication unit coupled to the first controller and the second port; and wherein, when the second controller receives the power demand request, provides a first notification to the first a controller, the first controller correspondingly communicates with the electric vehicle through the communication unit and controls the switch to be turned off, and when the first controller receives a feed-allowing notification from the electric vehicle, controls The switch is turned on to provide a feeding power from the electric vehicle to the first connection port from the second connection port through the power transmission path; when the first controller receives a feed from the electric vehicle When the charging is allowed to be notified, the first controller determines that the electric vehicle has a charging demand and controls the switch to be turned on, so as to provide a mains power from the mains to the second through the power transmission path from the first connection port port. The bidirectional AC charging device according to claim 1, wherein when the second controller receives a demand termination request, it correspondingly provides a second notification to the first controller, or when the first controller receives The first controller controls the switch to be turned off when a notification of power feeding is terminated. The bidirectional AC charging device according to claim 2, wherein when the first controller receives the first notification, the communication unit uses a second signal for communication; when the first controller receives the second notification Or the communication unit uses a first signal for communication when the power feeding is terminated. The bidirectional AC charging device according to claim 1, further comprising: an auxiliary power supply circuit, including a first conversion circuit and a second conversion circuit, the first conversion circuit and/or the second conversion circuit convert the power A power on the transmission path is an auxiliary power source. The bidirectional AC charging device as claimed in claim 1, further comprising: a detection circuit coupled to the power transmission path and the first controller, and detecting a power of the power transmission path to generate a power information signal ; wherein, the first controller controls the switch to be turned on or off according to the power information signal. The bidirectional AC charging device of claim 5, wherein the power transmission path includes a first path from the first connection port to the switch and a second path from the switch to the second connection port, and the detecting The circuit includes: a first voltage detection unit, which detects the voltage of the first path and provides a first voltage signal; a frequency detection unit, which detects the frequency of the power transmission path and provides a frequency signal; a current detection unit a detecting unit, detecting the current of the power transmission path and providing a current signal; a residual current detecting unit, detecting the residual current of the power transmission path and providing a residual current signal; and a second voltage detecting unit, detecting The voltage of the second path is measured to provide a second voltage signal; wherein, the power information signal includes the first voltage signal, the frequency signal, the current signal, the residual current signal and the second voltage signal. The bidirectional AC charging device according to claim 6, wherein the first controller determines whether an overvoltage or an undervoltage occurs in the mains according to the first voltage signal, and determines whether the electric vehicle is not based on the second voltage signal The overvoltage or the undervoltage occurs; the first controller determines whether an overcurrent occurs in the power transmission path according to the current signal, and determines the power transmission path according to the frequency signal. Whether an over-frequency or an under-frequency occurs in the transmission path, and whether a leakage current occurs in the power transmission path according to the residual current signal; when the over-voltage, under-voltage, over-current, over-frequency, and under-frequency occur Or when the leakage current occurs, the first controller controls the switch not to conduct. A method for operating a bidirectional AC charging device, comprising the following steps: (a) receiving a power request from a commercial power management system through a second controller; (b) when the second controller receives the power request Notifying a first controller so that the first controller communicates with an electric vehicle after switching from a first signal to a second signal through a communication unit, and controls a power transmission path to be non-conductive; (c1) when the When the first controller receives a feed permission notification, it controls the power transmission path to be turned on, so as to provide a feed power from an electric vehicle to a commercial power through the power transmission path; and (c2) when the first When the controller receives a charging permission notification from the electric vehicle, it determines that the electric vehicle has a charging demand and controls the power transmission path to be turned on, so as to provide a mains power from the mains to the electric vehicle through the power transmission path Electric vehicle. The operation method according to claim 8, further comprising: (d) notifying the first controller when the second controller receives a demand suspension request, so that the first controller can communicate with the second controller through the communication unit After the signal is switched to the first signal, it communicates with the electric vehicle, and controls the power transmission path to be non-conductive. The operation method as claimed in claim 8, further comprising: (d) when the first controller receives a notice of suspension of power feeding, switching from the second signal to the first signal through the communication unit and communicating with the electric motor The vehicle communicates, and the power transmission path is controlled to be non-conductive. The operation method as described in claim 8, further comprising: (e) Converting a power on the power transmission path into an auxiliary power source by a first converting circuit and/or a second converting circuit. The operation method of claim 8, further comprising: detecting a power of the power transmission path to generate a power information signal; and the first controller controlling the power transmission path to be turned on or off according to the power information signal . The operation method of claim 12, further comprising: when the first controller determines that the power has an overvoltage, an undervoltage, an overcurrent, an overfrequency, an underfrequency or an overvoltage according to the power information signal When leakage current occurs, the power transmission path is controlled to be non-conductive.

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