Charge control system for electric vehicle and electric vehicle

1. A charge control system for an electric vehicle, comprising:

a charge-discharge socket;

a three-level bidirectional DC-AC module having a first DC terminal configured to connect with a first terminal of a power battery of the electric vehicle and a second DC terminal configured to connect with a second terminal of the power battery;

a charge-discharge control module having a first terminal connected with an AC terminal of the three-level bidirectional DC-AC module and a second terminal connected with the charge-discharge socket;

a filtering module having a first terminal connected to the AC terminal of the three-level bidirectional DC-AC module and a second terminal connected to the charge-discharge control module; and

a control module connected with a third terminal of the charge-discharge control module and configured to control the charge-discharge control module to turn on, to sample an output voltage of an external grid by using a connection midpoint of filtering capacitors in the filtering module as a reference point, and to control the three-level bidirectional DC-AC module according to the output voltage of the external grid to control the external grid to charge the power battery, when the external grid is in an angle connection mode and the electric vehicle is in a charge-discharge mode;

wherein the three-level bidirectional DC-AC module comprises:

a first capacitor and a second capacitor connected in series and connected between the first DC terminal and the second DC terminal of the three-level bidirectional DC-AC module, a first node is defined between the first capacitor and the second capacitor;

a first IGBT and a second IGBT connected in series and connected between the first DC terminal and the second DC terminal of the three-level bidirectional DC-AC module, a second node is defined between the first IGBT and the second IGBT;

a third IGBT and a fourth IGBT connected in series and connected between a third terminal of the filtering module and the second node;

a fifth IGBT and a sixth IGBT connected in series and connected between the first DC terminal and the second DC terminal of the three-level bidirectional DC-AC module, a third node is defined between the fifth IGBT and the sixth IGBT;

a seventh IGBT and an eighth IGBT connected in series and connected between the third terminal of the filtering module and the third node;

a ninth IGBT and a tenth IGBT connected in series and connected between the first DC terminal and the second DC terminal of the three-level bidirectional DC-AC module, a fourth node is defined between the ninth IGBT and the tenth IGBT; and

an eleventh IGBT and a twelfth IGBT connected in series and connected between the third terminal of the filtering module and the fourth node;

wherein the second node, the third node and the fourth node are configured as the AC terminal of the three-level bidirectional DC-AC module.

2. The charge control system according to claim 1 , further comprising:

a motor control switch having a first terminal connected with the AC terminal of the three-level bidirectional DC-AC module and a second terminal configured to connect with a motor for the electric vehicle;

wherein the control module is connected with a third terminal of the motor control switch, and is configured to control the motor control switch to turn off when the electric vehicle is the charge-discharge mode.

3. The charge control system according to claim 1 , further comprising:

a first common-mode capacitor and a second common-mode capacitor connected in series and connected between the first terminal and the second terminal of the power battery, in which a node between the first common-mode capacitor and the second common-mode capacitor is grounded.

4. The charge control system according to claim 1 , further comprising:

a filtering control module connected between the first node and the third terminal of the filtering module, in which the control module controls the filtering control module to turn off when the electric vehicle is a driving mode.

5. The charge control system according to claim 4 , wherein a terminal of the filtering control module connected with the first node is configured to be the reference point.

6. The charge control system according to claim 1 , wherein the filtering module comprises three filtering capacitors connected in parallel.

7. The charge control system according to claim 1 , further comprising:

an EMI-filter module connected between the charge-discharge socket and the charge-discharge control module and configured to filter interference of conduction and radiation.

8. The charge control system according to claim 1 , further comprising:

a pre-charging control module connected with the charge-discharge control module in parallel and configured to pre-charge the filtering capacitors in the filtering module.

9. The charge control system according to claim 1 , wherein the charge-discharge control module comprises:

a three-phase switch and/or a single-phase switch configured to implement a three-phase charge-discharge or a single-phase charge-discharge.

10. An electric vehicle comprising the charge control system for an electric vehicle according to claim 1 .