JP2013219928A - In-band communication device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve communication quality by integrating a CPLT output/detection circuit and an in-band communication device while suppressing a waveform distortion, in in-band communication in which a communication signal is superposed on a CPLT signal in a vehicle charging system.SOLUTION: An in-band communication device includes: first and second bias adjustment circuits 207 and 208 including series circuits including switching elements 207-1 and 208-1 and inductors 207-2 and 208-2, which are switched on and off based on CPLT signal output logical values from a CPLT output controller 201 in a controller 103-1, respectively, and having one ends connected to positive and negative power supply voltages, respectively, and the other ends connected in common to a common connection portion of first and second coupling capacitors 205 and 206 connected to transmission/reception circuits 203 and 204 in a modem unit 103-2 for modulating/demodulating an in-band communication signal, respectively; and a standard resistor 209 having one end connected to the common connection portion, and the other end connected to a signal line side terminal CPLT of a CPLT line.

Description

  The present invention relates to an in-band communication device in a vehicle charging system.

  In recent years, plug-in hybrid vehicles and EV vehicles (electric vehicles: electric vehicles) have been rapidly developed (hereinafter collectively referred to as “vehicles”), and charging stations for charging vehicles are expected to become popular. . Under such circumstances, the need for mutual communication between the vehicle and the charging station, such as authentication and billing of the vehicle at the time of charging, or transmission of vehicle-specific information (for example, battery information (SOC)) to the user terminal. Is expected to increase.

As one of the communication media candidates between the vehicle and the charging station, an in-band (hereinafter referred to as “Inband”) that superimposes a communication signal on a control pilot (Control Pilot: hereinafter referred to as “CPLT”) signal for communicating a charging control signal. Communication method).
The communication circuit configuration of the CPLT signal is standardized and described in IEC (International Electrotechnical Commission) and SAE (American Automotive Engineers Association). Also, the standardization of the configuration of the Inband communication apparatus is being studied, and standardization is being promoted by IEC-ISO (International Organization for Standardization) 15118 and the like.

  Now, when the charging control signal is communicated between the vehicle and the charging station by the Inband communication method, the charging station side is defined as a CPLT signal output circuit or a communication standard for the CPLT signal as a circuit for outputting the CPLT signal. In addition, a standard resistor having a value of 1 kΩ (kiloohms), a CPLT detection circuit, and the like are additionally required, which increases the circuit scale. When attempting to connect the modem unit of the inband communication device to the configuration of such a CPLT output / detection circuit simply through the coupler unit, there is one type depending on the connection relationship between the standard resistor and the coupling capacitor in the coupler unit. The low-pass filter is formed. As a result, the CPLT signal waveform is distorted, the communication quality of the CPLT signal is deteriorated, and in the worst case, there is a problem that charging control is hindered.

JP 2010-098779 A

  In view of the above problems, the present invention provides an inband communication apparatus that suppresses the circuit scale and sufficiently ensures the quality of a CPLT signal.

  The present invention is an in-band communication apparatus for performing in-band communication by superimposing a communication signal on a CPLT signal with a vehicle at a charging station, and a control unit for outputting and detecting a control pilot signal, A modem unit that modulates and demodulates a signal, first and second coupling capacitors each having one end connected to the output and input of the modem unit and the other end connected in common, and each end having a positive power supply Are connected to the common connection of the first and second coupling capacitors, and are turned on based on the control pilot signal output logic value output from the control unit. Alternatively, the first and second bias adjustment circuits including a series circuit of a switching element to be turned off and an inductor, and one end of the first and second bias adjustment circuits. Beauty is connected to the common connection portion of the second bias adjustment circuit, and a standard resistor the other end of which is connected to control pilot signal line between the vehicle and the charging station.

  According to the present invention, the CPLT output / detection circuit and the in-band communication device can be integrated to realize downsizing of the device and improvement of CPLT communication quality.

It is a system configuration figure of this embodiment. It is a block diagram of one Embodiment of the Inband communication apparatus in a charging stand. It is a block diagram of the Inband communication apparatus in the charge stand considered generally. It is the figure which showed the example of the pulse width modulation waveform of this embodiment and the control pilot signal generally considered. It is a block diagram of other embodiment of the Inband communication apparatus in a charging stand.

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.
FIG. 1 is a system configuration diagram of this embodiment.
In this embodiment, the connector 106 of the charging cable (or in-vehicle charging cable) of the charging stand 102 is fitted to an inlet (not shown) on the vehicle 101 side such as a plug-in hybrid vehicle (or EV vehicle), in particular, The battery 112 in the vehicle 101 is charged. The charging cable includes a power line 109 connected to the system power 107 and a CPLT line (signal line, ground line) 108 for performing in-band communication (hereinafter referred to as “Inband communication”) on the CPLT (control pilot) signal and the CPLT signal. including. A power line 109 connected to the system power 107 is connected to a charger 111 in the vehicle 101 through a connector 106 and an inlet on the vehicle side from a charging circuit 105 that controls the start / stop of charging. The CPLT line 108 is grounded on the ground line side, and the signal line side is connected to the CPLT circuit 103-3 in the Inband communication device 103 in the charging station 102 and the CPLT detection circuit 110 in the vehicle 101. The charging station 102 outputs a CPLT signal instructing charging from the CPLT circuit 103-3 during the charging period. When the CPLT signal is detected by the CPLT detection circuit 110 in the vehicle 101, a charging instruction is issued to the charger 111, and the charger 111 starts charging the battery 112 from the power line 109.

  Operations such as performing vehicle authentication and charging at the time of charging, and transmitting vehicle-specific information (for example, battery information (SOC)) to the user terminal are performed by Inband communication device 104 in vehicle 101 and Inband communication in charging stand 102. This is implemented by exchanging communication signals with the apparatus 103.

  In this case, the Inband communication device 104 in the vehicle 101 and the Inband communication device 103 in the charging station 102 perform Inband communication of a communication signal using the CPLT line 108 in the charging cable. For example, when a communication signal is transmitted from the vehicle 101 to the charging station 102, the modem unit 104-2 is controlled by the control unit 104-1 controlling the modem unit 104-2 in the inband communication device 104 in the vehicle 101. The communication signal modulated in (1) is superimposed on the CPLT line 108 from the coupler section 104-3. This communication signal is received by the Inband communication device 103 in the charging station 102 via the CPLT circuit 103-3, demodulated by the modem unit 103-2, and received by the control unit 103-1. Conversely, when a communication signal is transmitted from the charging station 102 to the vehicle 101, the modem unit 103 is controlled by the control unit 103-1 controlling the modem unit 103-2 in the Inband communication device 103 in the charging station 102. -2 modulated signal is superimposed on the CPLT line 108 via the CPLT circuit 103-3. This communication signal is received by the inband communication device 104 in the vehicle 101 via the coupler unit 104-3, demodulated by the modem unit 104-2, and received by the control unit 104-1.

FIG. 2 is a block diagram of the Inband communication device 103 in the charging station 102 of FIG.
As described above, the control unit 103-1 controls the output and detection of the CPLT signal. More specifically, the control unit 103-1 includes a CPLT output control unit 201 that controls the output of the CPLT signal. Control unit 103-1 includes CPLT detection unit 202 that detects the state of the CPLT signal. In addition, the control unit 103-1 also controls transmission and reception of communication signals for Inband communication.

  As described above, the modem unit 103-2 modulates and demodulates a communication signal for Inband communication. More specifically, modem unit 103-2 includes a transmission circuit 203 that modulates a communication signal instructed to be output from control unit 103-1, and transmits the modulated communication signal. The modem unit 103-2 includes a receiving circuit 204 that demodulates the received modulated communication signal and outputs the demodulated communication signal to the control unit 103-1.

  A first coupling capacitor 205 and a second coupling capacitor 206 are provided in the modem unit 103-2 (may be outside). One end of the first coupling capacitor 205 is connected to the output of the modem unit 103-2, that is, the transmission circuit 203. One end of the second coupling capacitor 206 is connected to the input of the modem unit 103-2, that is, the reception circuit 204. The other ends of the first coupling capacitor 205 and the second coupling capacitor 206 are connected in common.

  The first bias adjustment circuit 207 includes a switching element 207-1 and an inductor 207-2 that are turned on or off based on a CPLT signal output logic value output from the CPLT output control unit 201 in the control unit 103-1. Including a series circuit, one end is connected to a positive power supply voltage of, for example, + 12V (volt). The second bias adjustment circuit 208 includes a switching element 208-1 and an inductor 208-2 that are turned on or off based on a CPLT signal output logic value output from the CPLT output control unit 201 in the control unit 103-1. Including a series circuit, one end is connected to a negative power supply voltage of, for example, -12 V (volts). The other end of the first bias adjustment circuit 207 (the other end of the inductor 207-2) and the other end of the second bias adjustment circuit 208 (the other end of the inductor 208-2) are the first and second coupling capacitors. 205 and 206 are connected in common to the common connection portion.

  The standard resistor 209 is a resistor having a resistance value of 1 kΩ (kiloohm) defined by the communication standard of the CPLT signal between the charging station 102 and the vehicle 101. One end of the standard resistor 209 is connected to the common connection portion of the first and second bias adjustment circuits 207 and 208, and the other end is connected to the signal line side terminal (CPLT in FIG. 2) of the CPLT line 108 in FIG. Is done. The CPLT signal is divided by the standard resistor 209 and the load in the vehicle 101, and the CPLT detection circuit 110 on the vehicle 101 side detects the voltage applied to the load on the vehicle 101 side.

The ground line of the CPLT line 108 is connected to a ground terminal (Earth in FIG. 2).
In the configuration of the embodiment of FIG. 1, in the charging stand 102, a CPLT output / detection circuit that has been different from the conventional configuration is integrated with the Inband communication device 103 as a CPLT circuit 103-3.

  As shown in FIG. 2, the CPLT circuit 103-3 includes first and second bias adjustment circuits 207 connected to positive and negative power supply voltages arranged in front of the standard resistor 209 (on the modem unit 103-2 side). 208, inductors 207-2 and 208-2 are inserted.

  When considering the integration of the CPLT output / detection circuit with the Inband communication device 103, a configuration that is generally easily considered is a configuration as shown in FIG. Here, in FIG. 3, the same number is attached | subjected to the part which has the same function as the case of FIG. In the configuration of FIG. 3, the first and second coupling capacitors 205 and 206 in the modem unit 103-2 corresponding to the conventional coupler unit are simply connected to the subsequent stage (on the CPLT line 108 side) of the standard resistor 209. Yes. On the other hand, a CPLT circuit 103-3 ′ corresponding to the CPLT circuit 103-3 in FIG. 2 is connected to a different system from the first and second coupling capacitors 205 and 206. That is, a configuration in which the CPLT output / detection circuit and the Inband communication apparatus, which have been conventionally separated, are simply connected in parallel to the CPLT line 108 and integrated is generally conceivable. The bias adjustment circuit connected to the positive / negative power supply voltage in the CPLT circuit 103-3 'is generally switching elements 207-1 and 208-1 connected in common to the standard resistor 209 as shown in FIG. Consists of only.

  However, in such a generally easily conceivable configuration, a kind of low-pass filter is formed by the first and second coupling capacitors 205 and 206 in the modem unit 103-2 and the standard resistor 209 in the CPLT circuit 103-3 '. Will be formed. As a result, there is a problem in that the pulse width modulation (PWM) waveform of the CPLT signal is distorted and communication quality is deteriorated.

  In contrast, in the configuration of the present embodiment shown in FIG. 2, the inductor 207-2 is connected in series with the switching elements 207-1 and 208-1 in the first and second bias adjustment circuits 207 and 208, respectively. And 208-2 are inserted. The common connection portion of the first and second coupling capacitors 205 and 206 is connected to the common connection portion of the inductors 207-2 and 208-2. With this configuration, distortion of the PWM waveform of the CPLT signal can be suppressed.

  FIG. 4 is a diagram showing an example of a PWM waveform of a control pilot signal processed in each of the configuration of the present embodiment shown in FIG. 2 and the configuration that can be generally easily considered shown in FIG. Reference numeral 401 denotes a waveform example according to the present embodiment, and reference numeral 402 denotes a waveform example having a configuration that can be generally easily considered. As is clear from the comparison of the waveform examples, the distortion of the waveform is well suppressed in this embodiment, which makes it possible to downsize the charging stand 102 system and improve the communication quality.

  The configuration shown in FIG. 2 is the minimum configuration that satisfies the technical scope of the present invention. In the minimum necessary configuration, the first bias adjustment circuit 207 includes a series part of the switching element 207-1 and the inductor 207-2, and the second bias adjustment circuit 208 includes the switching element 208-1 and the inductor 208-2. It includes a series part. A configuration in which an additional circuit element is further included is included in the technical scope of the present invention.

  FIG. 5 is a block diagram of another embodiment of the Inband communication device 103 in the charging station 102. In FIG. 5, parts having the same functions as those in the embodiment of FIG. 2 are given the same numbers.

  The configuration of the other embodiment of FIG. 5 is different from the configuration of the embodiment of FIG. 2 in that the component of the communication signal of Inband communication that is connected in parallel to the standard resistor 209 and blocks the component of the CPLT signal and is modulated is It is a point further provided with a bypass capacitor 501 (bypass circuit) to be passed.

  Thereby, since the communication signal of Inband communication passes not the standard resistor 209 but the bypass capacitor 501 side, it is possible to further suppress the attenuation caused by the communication signal passing through the standard resistor 209, and the communication quality is improved. Further improve.

  In FIG. 5, instead of the bypass capacitor 501, a bypass circuit such as a high-pass filter that passes only the component of the communication signal may be employed.

DESCRIPTION OF SYMBOLS 101 Vehicle 102 Charging stand 103,104 Inband communication apparatus 105 Charging circuit 106 Connector 107 System electric power 108 CPLT line 109 Power line 110 CPLT detection circuit 111 Charger 112 Battery 103-1, 104-1 Control part 103-2, 104-2 Modem 103-3 CPLT circuit 104-3 coupler unit 201 CPLT output control unit 202 CPLT detection unit 203 transmission circuit 204 reception circuit 205 first coupling capacitor 206 second coupling capacitor 207 first bias adjustment circuit 208 second Bias adjustment circuit 209 Standard resistance 207-1, 208-1 Switching element 207-2, 208-2 Inductor 501 Bypass capacitor

Claims (2)

An in-band communication device for performing in-band communication by superimposing a communication signal on a control pilot signal with a vehicle at a charging station, wherein the control unit outputs and detects the control pilot signal;
A modem unit for modulating and demodulating the communication signal;
First and second coupling capacitors each having one end connected to the output and input of the modem unit and each other connected in common;
One end is connected to the positive power supply voltage and the negative power supply voltage, and the other end is commonly connected to the common connection portion of the first and second coupling capacitors, and the control pilot signal is output from the control unit. First and second bias adjustment circuits including a series circuit of a switching element and an inductor that are turned on or off based on an output logic value;
One end is connected to a common connection part of the first and second bias adjustment circuits, and the other end is connected to the control pilot signal line between the vehicle and the charging station,
An in-band communication device comprising:   The in-band communication apparatus according to claim 1, further comprising a bypass circuit connected in parallel to the standard resistor and configured to block a component of the control pilot signal and pass a component of the modulated communication signal.