AC-DC photovoltaic device

• US 10,389,132 B2
• Filed: 03/30/2017
• Issued: 08/20/2019
• Est. Priority Date: 05/09/2016
• Status: Active Grant

• Current Assignee: Sungrow Power Supply Co., Ltd.
• Original Assignee: Sungrow Power Supply Co., Ltd.
• Inventors: Cao, Renxian, Gu, Yilei, Gu, Yu, Xu, Jun
• Primary Examiner(s): Barnie, Rexford N
• Assistant Examiner(s): Mourad, Rasem
• Application Number:
  US15/474,061
• Publication Number:
  US 20170324249A1
• Time in Patent Office: 873 Days
• CPC Class Codes: F21S 8/085 of high-built type, e.g. street light
• CPC Class Codes: F21S 9/03 rechargeable by exposure to light
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H02J 2300/24 of photovoltaic origin
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02M 1/0077 Plural converter units whose outputs are connected in series
• CPC Class Codes: H02M 1/10 Arrangements incorporating converting means for enabling loads to be operated at will from different kinds of power supplies, e.g. from ac or dc
• CPC Class Codes: H02M 1/126 using passive filters
• CPC Class Codes: H02M 3/158 including plural semiconductor devices as final control devices for a single load
• CPC Class Codes: H02M 7/487 Neutral point clamped inverters
• CPC Class Codes: H02M 7/53871 with automatic control of output voltage or current
• CPC Class Codes: H02M 7/5395 by pulse-width modulation
• CPC Class Codes: H02P 7/28 using semiconductor devices
• CPC Class Codes: Y02E 10/56 Power conversion systems, e.g. maximum power point trackers

Abstract

An AC-DC photovoltaic device is provided, including: a photovoltaic module, a direct current side capacitor, a DC-PWM power switching circuit and a controller. The direct current side capacitor is connected in parallel with an output terminal of the photovoltaic module. An input terminal of the DC-PWM power switching circuit is connected with the output terminal of the photovoltaic module. The DC-PWM power switching circuit includes a controllable switch transistor. The controller is configured to output a switch control signal to control a switching state of the controllable switch transistor in the DC-PWM power switching circuit, to control the DC-PWM power switching circuit to output a direct current PWM wave in a case that the switch control signal is a direct current modulation signal, and output an alternating current PWM wave in a case that the switch control signal is an alternating current modulation signal.

Claims

1. An alternating-current direct-current (AC-DC) photovoltaic device, comprising:

a photovoltaic module,

a direct current side capacitor,

a direct current pulse width modulation (DC-PWM) power switching circuit, and

a controller, wherein

the direct current side capacitor is connected in parallel with an output terminal of the photovoltaic module;

an input terminal of the DC-PWM power switching circuit is connected with the output terminal of the photovoltaic module;

the DC-PWM power switching circuit comprises a controllable switch transistor;

the controller is configured to output a switch control signal to control a switching state of the controllable switch transistor in the DC-PWM power switching circuit, comprising;

outputting a direct current modulation signal as the switch control signal to control the DC-PWM power switching circuit to output a direct current PWM wave and outputting an alternating current modulation signal as the switch control signal to control the DC-PWM power switching circuit to output an alternating current PWM wave.

2. The AC-DC photovoltaic device according to claim 1, wherein the DC-PWM power switching circuit is a full-bridge circuit.

3. The AC-DC photovoltaic device according to claim 1, wherein the DC-PWM power switching circuit is a three-level inverter topology circuit.

4. The AC-DC photovoltaic device according to claim 1, wherein

the DC-PWM power switching circuit is configured to output the direct current PWM wave;

and

a load is a direct current motor or a Light Emitting Diode (LED) streetlamp.

5. The AC-DC photovoltaic device according to claim 2, wherein

the DC-PWM power switching circuit is configured to output the direct current PWM wave;

and

a load is a direct current motor or a Light Emitting Diode (LED) streetlamp.

6. The AC-DC photovoltaic device according to claim 3, wherein

the DC-PWM power switching circuit is configured to output the direct current PWM wave;

and

a load is a direct current motor or a Light Emitting Diode (LED) streetlamp.

7. The AC-DC photovoltaic device according to claim 1, wherein

the DC-PWM power switching circuit is configured to output the direct current PWM wave;

and

a plurality of the AC-DC photovoltaic devices are connected in series to supply power to a high-voltage direct current communication system.

8. The AC-DC photovoltaic device according to claim 2, wherein

the DC-PWM power switching circuit is configured to output the direct current PWM wave;

and

a plurality of the AC-DC photovoltaic devices are connected in series to supply power to a high-voltage direct current communication system.

9. The AC-DC photovoltaic device according to claim 3, wherein

the DC-PWM power switching circuit is configured to output the direct current PWM wave;

and

a plurality of the AC-DC photovoltaic devices are connected in series to supply power to a high-voltage direct current communication system.

10. The AC-DC photovoltaic device according to claim 1, wherein

the DC-PWM power switching circuit is configured to output the direct current PWM wave;

and

a plurality of the AC-DC photovoltaic devices are connected in series or in series-parallel, and then connected with an input terminal of an inverter, an output terminal of the inverter is connected with an alternating current grid.

11. The AC-DC photovoltaic device according to claim 2, wherein

the DC-PWM power switching circuit is configured to output the direct current PWM wave;

and

a plurality of the AC-DC photovoltaic devices are connected in series or in series-parallel, and then connected with an input terminal of an inverter, an output terminal of the inverter is connected with an alternating current grid.

12. The AC-DC photovoltaic device according to claim 3, wherein

the DC-PWM power switching circuit is configured to output the direct current PWM wave;

and

a plurality of the AC-DC photovoltaic devices are connected in series or in series-parallel, and then connected with an input terminal of an inverter, an output terminal of the inverter is connected with an alternating current grid.

13. The AC-DC photovoltaic device according to claim 1, wherein

the DC-PWM power switching circuit is configured to output the alternating current PWM wave;

and

a plurality of the AC-DC photovoltaic devices are connected in series to supply power to a household appliance, or connected in series and then connected with an alternating current grid, or connected in series-parallel and then connected with an alternating current grid.

14. The AC-DC photovoltaic device according to claim 2, wherein

the DC-PWM power switching circuit is configured to output the alternating current PWM wave;

and

a plurality of the AC-DC photovoltaic devices are connected in series to supply power to a household appliance, or connected in series and then connected with an alternating current grid, or connected in series-parallel and then connected with an alternating current grid.

15. The AC-DC photovoltaic device according to claim 3, wherein

the DC-PWM power switching circuit is configured to output the alternating current PWM wave;

and

a plurality of the AC-DC photovoltaic devices are connected in series to supply power to a household appliance, or connected in series and then connected with an alternating current grid, or connected in series-parallel and then connected with an alternating current grid.

16. The AC-DC photovoltaic device according to claim 1, further comprising:

a filter circuit, configured to filter a harmonic component out of the direct current PWM wave or the alternating current PWM wave outputted from the DC-PWM power switching circuit.

17. The AC-DC photovoltaic device according to claim 1, wherein the input terminal of the DC-PWM power switching circuit is directly connected with an output terminal of photovoltaic module;

and the controller is configured to monitor a status of photovoltaic module and to realize a maximum power point tracking.