Charging station for a hybrid or electric vehicle

Abstract

The invention relates to a station (1) for charging a hybrid or electric vehicle via a power grid, the station being capable of receiving an electrical signal from the grid, which electrical signal comprises: - a sinusoidal power signal at the frequency of the power grid, and - a data signal, periodically overlaid on the power signal, this data signal being obtained by modulating an information signal with a carrier whose frequency is higher than the frequency of the power signal, the station comprising a detection unit (30) comprising: - an analogue circuit (31), configured to extract the data signal from the signal coming from the grid, and - a digital circuit (33), configured to decode the data signal thus extracted.

Description

[0001] Charging station for hybrid or electric vehicles

[0002] The present invention relates to a charging terminal for a hybrid or electric vehicle.

[0003] The vehicle has, for example, a battery intended to power an electric machine for propelling the vehicle, this battery having a nominal voltage whose value may be 48V, or greater than 60V, being for example greater than 200V or 300V, or greater than 400V, or greater than 800V.

[0004] The charging station is connected to an electrical network, which can be a national network or a regional network, for example, allowing the charging of vehicle batteries via a power signal. To encourage users to distribute their electrical energy consumption, in order to smooth out the demand for electrical energy as much as possible, different tariffs, for example called "off-peak hours" or "peak hours", exist.

[0005] Information about a tariff change, along with other information, is sent by the network manager via a data signal superimposed on the power signal. In France, this data signal takes the form of a frame called Pulsadis and is generated by EDF®.

[0006] It is known to use a microcontroller to separate the data signal from the power signal to recover information from the data signal superimposed on the power signal. This solution is expensive and requires a dedicated microcontroller for this data signal extraction.

[0007] There is a need to further improve the detection by a charging station of a hybrid or electric vehicle of the sending to the electricity network of a data signal superimposed on the power signal, this data signal containing in particular information relating to the tariff applied to the consumption of electrical energy in the network.

[0008] The invention aims to meet this need and achieves this, according to one of its aspects, using a charging terminal for a hybrid or electric vehicle via an electrical network, the terminal being capable of receiving an electrical signal from the network, this signal comprising:

[0009] - a sinusoidal power signal at the frequency of the electrical network, and

[0010] - a data signal, superimposed punctually on the power signal, this data signal being obtained by modulating an information signal with a carrier whose frequency is higher than the frequency of the power signal, the terminal comprising a detection unit comprising:

[0011] - an analog circuit, configured to extract the data signal from the signal coming from the network, and

[0012] - a digital circuit, configured to decode the data signal thus extracted. The processing of the data signal by the terminal is advantageous because the extraction of the data signal from the signal coming from the network is carried out by an analog circuit, that is to say with components of reduced cost and without the need to develop a specific program for extraction by digital means.

[0013] The analog circuit has, for example, two inputs, one of these inputs being, for example, connected to a phase conductor of the electrical network and the other of these inputs being, for example, connected to the neutral connector of the electrical network.

[0014] The electrical network is, for example, three-phase, carrying a sinusoidal power signal whose effective value is, for example, 230V and whose frequency is, for example, 50 Hz or 60 Hz.

[0015] The analog circuit can implement a band-rejection filter to filter the power signal. This band-rejection filter has, for example, a center frequency of 50 Hz or 60 Hz.

[0016] This band-reject filter is, for example, a passive filter, using only resistors and capacitors, for example. The band-reject filter can therefore be without a coil. More generally, the analog circuit can be without a coil.

[0017] In this band-rejection filter, the capacitors have, for example, a capacity between 1 and 100 nF and the resistors have, for example, a value between 10 kΩ and 1000 kΩ.

[0018] The analog circuit may include an amplification stage at the output of the band-reject filter. The band-reject filter has, for example, two outputs, these two outputs forming a differential input for the amplification stage.

[0019] The amplification stage includes, for example, several operational amplifiers.

[0020] In this case, a first operational amplifier can receive on its non-inverting input a first output of the band reject filter, a second operational amplifier receives on its non-inverting input a second output of the band reject filter, and a third operational amplifier can receive on each of its inputs a signal respectively coming from the output of the first operational amplifier and from the output of the second operational amplifier. The output of this third operational amplifier can then define the single output of the amplification stage.

[0021] The amplification stage may include resistors and the values ​​of these resistors may be chosen so that the voltage gain of the amplification stage is between 1 and 50. The gain of this amplification stage is here the ratio between the output voltage of the amplification stage and the differential voltage at its input.

[0022] The resistors of the amplifier stage have, for example, a value between 1 kΩ and 100 kΩ.

[0023] The amplification stage may comprise a resistor connecting the inverting input of the first operational amplifier and the inverting input of the second operational amplifier, and the value of this resistor may be greater than 1 k / 2, for example greater than 1.2 k / 2 or greater than 1.23 k / 2.

[0024] The analog circuit can still implement a bandpass filter at the output of the amplification stage to extract the data signal. The use of a bandpass filter makes it possible to amplify the data signal while filtering out any residual power signal that would not have been filtered by the band-reject filter.

[0025] The bandpass filter can have a bandwidth between 3% and 10% of the data signal carrier frequency. This bandpass filter is for example a Butterworth filter, in particular an active filter of order 4. The bandpass filter has for example a voltage gain between 5 and 20, for example 8.

[0026] The bandpass filter uses, for example, resistors and capacitors whose respective values ​​can be between 1 k and 10000 kΩ and between 1 nF and 100 nF.

[0027] The carrier frequency of the data signal is, for example, greater than 3 times the frequency of the power signal. In a specific example, this carrier frequency of the data signal is between 170 Hz and 180 Hz, being, for example, equal to 175 Hz.

[0028] The output of the bandpass filter can be compared to a voltage threshold, for example via an additional operational amplifier, before crossing a galvanic isolation to attack the digital circuit. This galvanic isolation is for example provided by an optocoupler.

[0029] In all of the above, the analog circuit may have a power supply for all or some of the operational amplifiers. This power supply may provide a DC voltage of 12 V. It may be a non-isolated power supply.

[0030] The digital circuit can be configured to recover the information signal by demodulation, in order to decode this information signal. The digital circuit is for example a microcontroller.

[0031] The information signal is, for example, a sequence of binary pulses, for example a 40-bit frame of the same duration and spaced by the same time interval.

[0032] The superposition of the data signal with the power signal occurs for example several times a day, for example twice a day.

[0033] In all of the above, the charging station is, for example, configured to supply the vehicle with electrical power of between 7 kW and 22 kW, or more. The transfer of electrical energy between the charging station and the vehicle may be reversible, with the vehicle possibly being able to supply electrical energy to the station and therefore to the electricity network connected to it.

[0034] In all of the above, the charging station can be configured to exchange electrical energy with more than one vehicle simultaneously, for example with two vehicles. The station then has two separate connectors, each of these connectors allowing the exchange of electrical energy with a respective vehicle.

[0035] The terminal can be configured to communicate with a wireless data network.

[0036] The invention may be better understood by reading the following description of a non-limiting example of its implementation and by examining the attached drawing in which:

[0037] [Fig.l] represents an exploded view of a charging terminal according to an exemplary implementation of the invention, and

[0038] [Fig.2] shows a schematic diagram of the detection unit of the terminal of Figure 1, and [Fig.3] shows an example of the analog circuit of the detection unit of Figure 2.

[0039] Figure 1 shows a charging terminal 1 according to an exemplary implementation of the invention. This terminal 1 is intended to allow an exchange of electrical energy between a vehicle and an electrical network to which it is connected via a cable not shown in this figure. The vehicle may be a hybrid vehicle or an electric vehicle.

[0040] The electricity network is, for example, a national network carrying an alternating voltage with an effective value of 230V and a frequency of 50Hz. This voltage can be three-phase.

[0041] In the example considered, the terminal 1 comprises a housing formed by the joining of a rear frame 2 and a front frame 3 which are assembled together. A cover 4 is mounted on the periphery of the front frame 3, partly forming the front face of the terminal 1, that is to say its face facing the vehicle. A seal 19 is interposed between the front frame 3 and the rear frame 2 to ensure sealing inside the terminal housing.

[0042] Terminal 1 also includes a flap 5, selectively closing an opening 15 made in the front frame 3. This opening 15 allows the introduction into terminal 1 of an external connector mounted on a cable for connection to the vehicle's electrical circuit.

[0043] Terminal 1 further comprises a connector 8 which may be of the female type such as a socket or of the male type such as a plug. This connector 8 may be three-phase, in which case it comprises four electrical contacts, or single-phase, in which case it comprises two. Whatever the type of connector, the latter may also incorporate the earth and one or more communication contacts.

[0044] Terminal 1 also includes a support 13 carrying: - a contactor 7, capable of selectively interrupting the exchange of electrical energy with the vehicle, and

[0045] - a meter 6 to measure the quantity of electrical energy exchanged between terminal 1 and the vehicle. This meter 6 is for example designed to meet the requirements of the MID Directive.

[0046] In the example considered, the terminal also includes several electronic cards.

[0047] One of these cards is an electronic power card 10 carrying electronic components such as inductors or capacitors to provide in particular a filtering function. Other functions can be performed by this card 10, for example additional functions such as voltage conversion for the power supply of low voltage components or even a fuse function.

[0048] Another electronic card is an electronic control card 9, this card ensuring the control of the electronic power card 10. It can also manage the possible connection of the terminal 1 with a wireless data network and / or the connection with the vehicle. This card can also control an electronic human / machine interface card 11 and integrate a control unit 30 which will be described below.

[0049] The electronic human / machine interface card 11 carries, for example, an indicator light such as an LED informing the user of the availability or operating status of the terminal 1, as well as possibly an RFID function or a button that can be operated by the user.

[0050] The electronic cards 9 and 10 are for example screwed onto the support 13, while the electronic card 11 is directly mounted on the front frame 3 of the terminal.

[0051] Terminal 1 also includes a clamp 12 for holding in place on the rear frame 3 the cable (not shown) which is connected to the electrical network.

[0052] In addition to the power signal used to charge the vehicle, which here corresponds to a three-phase sinusoidal voltage with an effective value of 230V and a frequency of 50 Hz, this cable can also occasionally carry an additional data signal, which is superimposed on it. The data signal is, for example, sent twice a day into the electricity network.

[0053] This data signal is in the example considered constructed by modulating an information signal with a carrier whose frequency is higher than that of the power signal.

[0054] The information signal is in the example considered formed by a 40-bit frame following a start bit. Each bit here has a duration of 1 second and the bits of the frame are spaced apart by a duration of 1.5 seconds. Receiving each bit of the frame may correspond to a message, at least one of these messages comprising for example the update of a billing tariff for the electrical energy consumed in the electrical network.

[0055] The electronic control card 10 integrates in the example considered a detection unit 30 making it possible to process this data signal.

[0056] As can be seen in Figure 2, which is a block diagram of the detection unit 30, the latter comprises:

[0057] - an analog circuit 31,

[0058] - 32 galvanic isolation, and

[0059] - a digital circuit 33.

[0060] It can also be seen in Figure 2 that the detection unit 30 can interact with a voltage supply 34, this voltage supply 34 being for example supplied from the electronic power card 10.

[0061] The analog circuit 32 receives in the example considered two inputs, a first input being connected to a phase conductor P of the network and the second input being connected to the neutral N of this network.

[0062] The analog circuit processes these two inputs via a band-rejection filter 40 which will now be described. This band-rejection filter is here a passive filter, being formed exclusively by capacitors and resistors.

[0063] This band rejector filter 40 here has a center frequency of 50 Hz to filter as much as possible the power signal of the signal received at the input of the detection unit 30.

[0064] The capacitors of this band-rejection filter 40 have, for example, a value between 10 kΩ and 1000 kΩ. More precisely, in the example described, but in a non-limiting manner, the capacitors C23 and C24 are Y1 type film capacitors and have a capacity of 10 nF. The capacitors C10, C11, C13, C14 and C15 have a capacity of 22 nF.

[0065] For example, resistors have a value between 10 kΩ and 1000 kΩ. Specifically, in the example described, resistors R24 and R25 have a value of 100 kΩ, resistors R9, R10, R13, R16 and R12 have a value of 144 kΩ, and resistors R33, R34, R35 and R36 have a value of 15 kΩ.

[0066] The two outputs of this band-rejection filter 40 then drive an amplification stage 50, so that this amplification stage 50 has a differential input.

[0067] As can be seen in Figure 3, the amplification stage 50 contains in the example considered three operational amplifiers, respectively designated by U4, U7 and U8 in Figure 3. One of the outputs of the band-rejection filter 40 is received on the non-inverting input of the operational amplifier U4 and the other output of the band-rejection filter 40 is received on the non-inverting input of the operational amplifier U7.

[0068] It can be seen in Figure 3 that the respective inverting inputs of these operational amplifiers are connected together via a resistor R37.

[0069] The third operational amplifier U8 receives on each of its inputs a signal from an output of one of the operational amplifiers U4 and U7, and the output of this third operational amplifier constitutes the only output of the amplification stage 50 while the latter comprises two inputs.

[0070] Each of these operational amplifiers U4, U7 and U8 is here electrically powered by a direct voltage of 12V, via the aforementioned common power supply 34.

[0071] It can be seen in Figure 3 that the amplification stage 50 comprises, in addition to the three operational amplifiers U4, U7 and U8 mentioned above and the resistor R37, other resistors whose values ​​can be chosen so that the gain of the amplification stage 50 is between 1 and 50, for example between 3 and 23.

[0072] In the example considered, resistor R37 has a value of 15 kΩ, resistors R51 and R52 have a value of 24 kΩ, and resistors R53, R54, R55, R56, R60, R61, R40, R41, R45 and R46 have a value of 10 kΩ.

[0073] A fourth operational amplifier U10 is here arranged between the output of the second operational amplifier U7 and the input of the third operational amplifier U8.

[0074] In the example of Figure 3, the single output of the amplification stage 50 then drives a bandpass filter 60 arranged to amplify the data signal which here has a frequency of 175 Hz and to isolate it.

[0075] In the example considered, this bandpass filter 60 is an active Butterworth filter of order 4.

[0076] This Butterworth filter 60 here implements two operational amplifiers arranged in series, U5 and U1 which are, similarly to what has been described with reference to the amplification stage 50, electrically powered by a direct voltage of 12V. provided by the voltage supply 34

[0077] This Butterworth filter also includes resistors and capacitors sized to define a bandwidth between 3% and 10% of the data signal carrier frequency and to have a voltage gain between 5 and 20. The bandpass filter uses, for example, resistors and capacitors whose respective values ​​can be between 1 kΩ and 10000 kΩ and between 1 nF and 100 nF. In the example described, this bandwidth is [165 Hz; 183 Hz] and this voltage gain is 8. In this case:

[0078] - resistor R38 has a value of 147 kΩ

[0079] - resistor R39 has a value of 1.6 k

[0080] - resistor R42 has a value of 1180 kΩ,

[0081] - resistor R43 has a value of 137 kΩ,

[0082] - resistor R44 has a value of 1.5 kΩ,

[0083] - resistor R47 has a value of 1100 kΩ,

[0084] - resistors R45 and R46 have a value of 10 kΩ, and

[0085] - capacitors C17, C19, C20, C21 have a capacity of 22 nF.

[0086] The output of the bandpass filter 60 may be a voltage signal whose amplitude is between 5 V and 10 V and at the frequency of the carrier of the information signal.

[0087] This signal at the output of the bandpass filter 60 is here compared by a comparator 70 to a voltage threshold lower than the amplitude of said signal. This voltage threshold is here obtained using a voltage divider bridge and the 12V DC voltage supplied by the power supply 34. The comparator is in the example considered an operational amplifier U2 of which:

[0088] - the inverting input receives the output of the bandpass filter 60,

[0089] - the non-inverting input receives the output of the voltage divider bridge formed by two resistors R2 and R3, these resistors have for example a value of 7.5 kQ and 10 kQ respectively.

[0090] In all of the above, the aforementioned operational amplifiers may be of the same type, for example such as those marketed by Texas Instruments® under the reference LM358ADR.

[0091] The signal resulting from this comparison then crosses a galvanic isolation, carried out here via an optocoupler 32 before being processed by the digital circuit 33 which is here a microcontroller. As can be seen in Figure 3, the electrical power supply of the optocoupler 32 can also be provided by the power supply 34.

[0092] The digital circuit 33 here recovers the information signal by demodulation, in order to decode this information signal. It is thus possible to decode this information signal and, in the example considered, determine which of the 40 bits of the frame have been sent.

Claims

Demands 1. Charging station (1) for hybrid or electric vehicles via an electrical network, the station being capable of receiving an electrical signal from the network and comprising: - a sinusoidal power signal at the frequency of the electrical grid, and - a data signal, superimposed at specific points on the power signal, this data signal being obtained by modulating an information signal with a carrier whose frequency is higher than the frequency of the power signal, the terminal comprising a detection unit (30) comprising: - an analog circuit (31), configured to extract the data signal from the network signal, and - a digital circuit (33), configured to decode the data signal thus extracted.

2. Charging terminal according to the preceding claim, the analog circuit (31) implementing a band-reject filter (40) to filter the power signal.

3. Charging terminal according to the preceding claim, the analog circuit (31) implementing an amplification stage (50) of the signal at the output of the band-reject filter (40).

4. Charging station according to the preceding claim, the amplification stage (50) comprising several operational amplifiers.

5. Charging terminal according to the preceding claim, the amplification stage (50) comprising a first operational amplifier receiving on its non-inverting input a first output of the band-rejecting filter (40), a second operational amplifier receiving on its non-inverting input a second output of the band-rejecting filter (40), and a third operational amplifier receiving on each of its inputs a signal respectively from the output of the first operational amplifier and from the output of the second operational amplifier.

6. Charging terminal according to any one of claims 3 to 5, the analog circuit implementing a bandpass filter (60) at the output of the amplification stage (50) to extract the data signal.

7. Charging terminal according to claim 6, the bandpass filter (60) having a bandwidth between 3% and 10% of the data signal carrier frequency.

8. Charging terminal according to claim 6 or 7, the bandpass filter (60) being a Butterworth filter, in particular an active filter, in particular a 4th order active filter.

9. Charging station according to any one of the preceding claims, the digital circuit (33) being configured to recover the information signal by demodulation, in order to decode this information signal.

10. Charging terminal according to any one of the preceding claims, the information signal being a sequence of binary pulses.

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