Direct current conversion circuit

• US 9,257,904 B2
• Filed: 07/09/2013
• Issued: 02/09/2016
• Est. Priority Date: 11/16/2012
• Status: Active Grant

• Current Assignee: Industrial Technology Research Institute
• Original Assignee: Industrial Technology Research Institute
• Inventors: Tsai, Wen-Tien, Lee, Ching-Ran, Chen, Po-Yen, Pan, Ching-Tsai
• Primary Examiner(s): Vu, Jimmy
• Assistant Examiner(s): Chan, Wei
• Application Number:
  US13/937,685
• Publication Number:
  US 20140139128A1
• Time in Patent Office: 945 Days
• Field of Search: 315/209, 315/307, 315/244, 315/209.R, 315/247, 315/224, 363/81, 363/89, 363/132, 363/198, 363/34, 363/37, 363/39, 363/47, 363/98
• US Class Current: 1/1
• CPC Class Codes: H02M 1/0058 by employing soft switching techniques, i.e. commutation of transistors when applied voltage is zero or when current flow is zero using an auxiliary actively switched resonant commutation circuit connected to an intermediate DC voltage or between two push-pull branches of an inverter bridge H02M7/4811; in resonant inverters H02M7/4815; in inverters operating from a resonant DC source H02M7/4826
• CPC Class Codes: H02M 3/155 using semiconductor devices only
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A direct current (DC) conversion circuit suitable for driving a load comprises a buck-boost converter, a resonant stage circuit and an output stage circuit. The buck-boost converter has two input ends receiving a first DC signal, and two output ends outputting a second DC signal. The resonant stage circuit has two input ends receiving the second DC signal. The resonant stage circuit converts the second DC signal to energy and further converts the energy to a negative voltage by a resonance effect. The resonant stage circuit has two input ends outputting the energy. The output stage circuit has two input ends receiving the energy to store the energy, and two output ends outputting energy to the load.

Claims

1. A direct current (DC) conversion circuit, adapted to drive a load which comprises a light emitting diode or an organic solid-state lighting, and comprising:

a buck-boost converter having two input ends, a negative output end and a positive output end, the two input ends being used for receiving a first DC signal, and the negative and positive output ends being used for outputting a second DC signal;

a resonant stage circuit having two input ends and two output ends, used for receiving the second DC signal by the two input ends of the resonant stage circuit, converting the second DC signal to energy, and outputting the energy by the two output ends of the resonant stage circuit, and further used for converting the energy to a negative voltage by a resonance effect and outputting the energy by the two output ends of the resonant stage circuit, wherein the resonant stage circuit comprises;

a first diode having an anode end and a cathode end, the cathode end of the first diode being coupled to the positive output end of the buck-boost converter and one of the two input ends of the resonant stage circuit, and the anode end of the first diode being coupled to the negative output end of the buck-boost converter, the other one of the two input ends of the resonant stage circuit, and one of the two output ends of the resonant stage circuit; and

a resonant tank having a first inductor and a first capacitor coupled in parallel, wherein the resonant tank is coupled between the cathode of the first diode and the other one of the two output ends of the resonant stage circuit; and

an output stage circuit, having two input ends and two output ends, used for receiving the energy by the two input ends of the output stage circuit to store the energy and perform power charging, in order to output the energy to the load by the two output ends of the output stage circuit.

2. The DC conversion circuit as claimed in claim 1, wherein the resonant tank further comprises:

a second diode having an anode end and a cathode end, the anode end of the second diode being connected to the cathode end of the first diode and the first capacitor, and the cathode end of the second diode being coupled to the first inductor.

3. The DC conversion circuit as claimed in claim 1, wherein the resonant tank further comprises:

a second diode having an anode end and a cathode end, the anode end of the second diode being coupled between the first inductor, and the cathode end of the second diode being coupled to the other one of the two output ends of the resonant stage circuit and the first capacitor.

4. The DC conversion circuit as claimed in claim 1, wherein the output stage circuit comprises:

a second capacitor having a first end and a second end, the first end of the second capacitor being coupled to the one of the two output ends of the resonant stage circuit and one of the two input ends of the output stage circuit, and the second end of the second capacitor being coupled to the other one of the two output ends of the resonant stage circuit and the other one of the two input ends of the output stage circuit;

a third diode having an anode end and a cathode end, and the anode end of the third diode being coupled to the first end of the second capacitor; and

a second inductor having a first end and a second end, the first end of the second inductor being coupled to the cathode end of the third diode, and the second end of the second inductor being coupled to one of the two output ends of the output stage circuit and the load;

wherein the other one of the two output ends of the output stage circuit is directly coupled to the other one of the two input ends of the output stage circuit and the load.

5. The DC conversion circuit as claimed in claim 1, wherein the output stage circuit comprises:

a second capacitor having a first end and a second end, the first end of the second capacitor being coupled to one of the two output ends of the resonant stage circuit and one of the two input ends of the output stage circuit, and the second end of the second capacitor being coupled to the other one of the two output ends of the resonant stage circuit and the other one of the two input ends of the output stage circuit;

a second inductor having a first end and a second end, the first end of the second inductor being coupled to the first end of the second capacitor; and

a third diode having an anode end and a cathode end, and the anode end of the third diode being coupled to the second end of the second inductor, and the cathode end of the third diode being coupled to one of the two output ends of the output stage circuit and the load;

wherein the other one of the two output ends of the output stage circuit is directly coupled to the other one of the two input ends of the output stage circuit and the load.

6. The DC conversion circuit as claimed in claim 1, wherein one of the two the input ends of the output stage circuit is directly coupled to one of the two output ends of the output stage circuit, and the output stage circuit comprises:

a second capacitor having a first end and a second end, the first end of the second capacitor being coupled to one of the two output ends of the resonant stage circuit and one of the two input ends of the output stage circuit, and the second end of the second capacitor being coupled to the other one of the two output ends of the resonant stage circuit and the other one of the two input ends of the output stage circuit;

a third diode having an anode end and a cathode end, and the cathode end of the third diode being coupled to the second end of the second capacitor; and

a second inductor having a first end and a second end, the first end of the second inductor being coupled to the anode end of the third diode, and the second end of the second inductor being coupled to the other one of the two output ends of the output stage circuit and the load;

wherein the one of the two output ends of the output stage circuit is coupled to the load.

7. The DC conversion circuit as claimed in claim 1, wherein one of the two the input ends of the output stage circuit is directly coupled to one of the two output ends of the output stage circuit, and the output stage circuit comprises:

a second capacitor having a first end and a second end, the first end of the second capacitor being coupled to one of the two output ends of the resonant stage circuit and one of the two input ends of the output stage circuit, and the second end of the second capacitor being coupled to the other one of the two output ends of the resonant stage circuit and the other one of the two input ends of the output stage circuit;

a second inductor having a first end and a second end, the first end of the second inductor being coupled to the second end of the second capacitor; and

a third diode having an anode end and a cathode end, and the cathode end of the third diode being coupled to the second end of the second inductor, and the anode end of the third diode being coupled to the one of the two output ends of the output stage circuit and the load;

wherein the one of the two output ends of the output stage circuit is coupled to the load.

8. The DC conversion circuit as claimed in claim 1, wherein the output stage circuit comprises:

a second capacitor having a first end and a second end, the first end of the second capacitor being coupled to one of the two output ends of the resonant stage circuit and one of the two input ends of the output stage circuit, and the second end of the second capacitor being coupled to the other one of the two output ends of the resonant stage circuit and the other one of the two input ends of the output stage circuit;

a second inductor having a first end and a second end, the first end of the second inductor being coupled to the first end of the second capacitor, and the second end of the second inductor being coupled to one of the two output ends of the output stage circuit and the load; and

a third diode having an anode end and a cathode end, the cathode end of the third diode being coupled to the second end of the second capacitor, and the anode end of the third diode being coupled to the other one of the two output ends of the output stage circuit and the load.

9. The DC conversion circuit as claimed in claim 1, wherein the output stage circuit comprises:

a second capacitor having a first end and a second end, the first end of the second capacitor being coupled to one of the two output ends of the resonant stage circuit and one of the two input ends of the output stage circuit, and the second end of the second capacitor being coupled to the other one of the two output ends of the resonant stage circuit and the other one of the two input ends of the output stage circuit;

a third diode having an anode end and a cathode end, the anode end of the third diode being coupled to the first end of the second capacitor, and the cathode end of the third diode being coupled to one of the two output ends of the output stage circuit and the load; and

a second inductor having a first end and a second end, the first end of the second inductor being coupled to the second end of the second capacitor, and the second end of the second inductor being coupled to the other one of the two output ends of the output stage circuit and the load.

10. The DC conversion circuit as claimed in claim 1, wherein the first DC signal is a DC power source or a pulse power source.

11. The DC conversion circuit as claimed in claim 1, wherein the buck-boost converter comprises:

a switch having a first end, a second end and a third end, wherein the first end of the switch receives a control signal, the second end of the switch is coupled to one of the two input ends of the buck-boost converter, and the third end of the switch is coupled to the negative output end of the buck-boost converter;

a third inductor having a first end and a second end, wherein the first end of the third inductor is coupled to the other one of the two input ends of the buck-boost converter, and the second end of the third inductor is coupled to the third end of the switch; and

a fourth diode having an anode end and a cathode end, wherein the anode end of the fourth diode is coupled to the first end of the third inductor, and the cathode end of the fourth diode is coupled to the positive output end of the buck-boost converter.

12. The DC conversion circuit as claimed in claim 1, wherein the buck-boost converter comprises:

a switch having a first end, a second end and a third end, wherein the first end of the switch receives a control signal, the second end of the switch is coupled to one of the two input ends of the buck-boost converter;

a third inductor having a first end and a second end, wherein the first end of the third inductor is coupled to the third end of the switch and the second end of the third inductor is coupled to the other one of the two input ends of the buck-boost converter and the positive output end of the buck-boost converter; and

a fourth diode having an anode end and a cathode end, wherein the cathode end of the fourth diode is coupled to the first end of the third inductor, and the anode end of the fourth diode is coupled to the negative output end of the buck-boost converter.

13. The DC conversion circuit as claimed in claim 1, wherein the buck-boost converter comprises:

a switch having a first end, a second end and a third end, wherein the first end of the switch receives a control signal, the second end of the switch is coupled to one of the two input ends of the buck-boost converter;

a third inductor having a first end and a second end, wherein the first end of the third inductor is coupled to the third end of the switch and the second end of the third inductor is coupled to the other one of the two input ends of the buck-boost converter and the negative output end of the buck-boost converter; and

a fourth diode having an anode end and a cathode end, wherein the anode end of the fourth diode is coupled to the first end of the third inductor, and the cathode end of the fourth diode is coupled to the positive output end of the buck-boost converter.

14. The DC conversion circuit as claimed in claim 1, wherein the buck-boost converter comprises:

a switch having a first end, a second end and a third end, wherein the first end of the switch receives a control signal, the second end of the switch is coupled to one of the two input ends of the buck-boost converter, and the third end of the switch is coupled to the positive output end of the buck-boost converter;

a third inductor having a first end and a second end, wherein the first end of the third inductor is coupled to the other one of the two input ends of the buck-boost converter, and the second end of the third inductor is coupled to the third end of the switch; and

a fourth diode having an anode end and a cathode end, wherein the cathode end of the fourth diode is coupled to the first end of the third inductor, and the anode end of the fourth diode is coupled to the negative output end of the buck-boost converter.

15. A direct current (DC) conversion circuit, adapted to drive a load which comprises a light emitting diode or an organic solid-state lighting, and comprising:

a buck-boost converter having two input ends, a negative output end and a positive output end, the two input ends being used for receiving a first DC signal, and the negative and positive output ends being used for outputting a second DC signal;

a resonant stage circuit having two input ends and two output ends, used for receiving the second DC signal by the two input ends of the resonant stage circuit, converting the second DC signal to energy, and outputting the energy by the two output ends of the resonant stage circuit, and further used for converting the energy to a negative voltage by a resonance effect and outputting the energy by the two output ends of the resonant stage circuit, wherein the resonant stage circuit comprises;

a first diode having an anode end and a cathode end, the cathode end of the first diode being coupled to the positive output end of the buck-boost converter, the one of the two input ends of the resonant stage circuit and one of the two output ends of the resonant stage circuit, and the anode end of the first diode being coupled to the negative output end of the buck-boost converter and the other one of the two input ends of the resonant stage circuit; and

a resonant tank having a first inductor and a first capacitor coupled in parallel, wherein the resonant tank is coupled between the anode of the first diode and the other one of the two output ends of the resonant stage circuit; and

an output stage circuit, having two input ends and two output ends, used for receiving the energy by the two input ends of the output stage circuit to store the energy and perform power charging, in order to output the energy to the load by the two output ends of the output stage circuit.

16. The DC conversion circuit as claimed in claim 15, wherein the resonant tank further comprises:

a second diode having an anode end and a cathode end, the cathode end of the second diode being coupled to the anode end of the first diode and the first capacitor, and the anode end of the second diode being coupled to the first inductor.

17. The DC conversion circuit as claimed in claim 15, wherein the resonant tank further comprises:

a second diode having an anode end and a cathode end, the cathode end of the second diode being coupled to the first inductor, and the anode end of the second diode being coupled to the other one of the two output ends of the resonant stage circuit and the first capacitor.