Centralized device for the control of the feeding voltage of a load provided with a power factor correction condenser

• US 20050062437A1
• Filed: 02/13/2003
• Published: 03/24/2005
• Est. Priority Date: 02/15/2002
• Status: Active Grant

• Current Assignee: Reverberi Enetec S.R.I.
• Original Assignee: Elettronica Reverberi S. R. I
• Inventors: Numeroli, Renato, Porta, Luca
• Granted Patent: US 7,288,904 B2
• Time in Patent Office: Days
• US Class Current: 315/247
• CPC Class Codes: H02M 5/293 using semiconductor devices only
• CPC Class Codes: H05B 39/048 with reverse phase control
• CPC Class Codes: H05B 41/3924 by phase control, e.g. using a triac H05B41/3922 takes precedence

Abstract

A centralized device for supply voltage control of a load with power factor correction condensers for lighting engineering applications has an array converter for obtaining a portion of power, with a plurality of switches located between the network sinusoidal supply and the load. The centralized device has controlling and regulating means for managing both the activation and deactivation states of the switches of the array converter so as to avoid sudden voltage changes across the load and provide for control of the load voltage.

Claims

1. A centralized device for supply voltage control of a load with power factor correction condensers for lighting engineering applications, comprising:

a power portion including an array converter, which has a plurality of switching means located between the network sinusoidal supply and the load,

and controlling and regulating means for managing the activation and deactivation states of said switching means of said array converter, thus avoiding application to the load of sudden voltage changes and ensuring control of continuous voltage values of the load, wherein said controlling and regulating means are connected to sensing means from which they receive information on the values reached by the load voltage and current and supply voltage, and in that, based on the voltage and current measurements through said sensing means, said controlling and regulating means can automatically select the most correct operating procedure between a set of operating procedures.

2. A centralized device for supply voltage control of a load with power factor correction condensers for lighting engineering applications according to claim 1, wherein said set of procedures consists of three predetermined operating procedures.

3. A centralized device for supply voltage control of a load with power factor correction condensers for lighting engineering applications according to claim 1 wherein one of said operating procedures is for the loads mainly capacitive features.

4. A centralized device for supply voltage control of a load with power factor correction condensers for lighting engineering applications according to claim 1 wherein one of said operating procedures is for the loads having mainly inductive features.

5. A centralized device for supply voltage control of a load with power factor correction condensers for lighting engineering applications according to claim 1 wherein one of said operating procedures is for the intermediate loads.

6. A centralized device for supply voltage control of a load with power factor correction condensers for lighting engineering applications according to claim 4 wherein said controlling and regulating means are adapted to said information received from the sensing means, thus being able to decide in advance the passage from the operating procedure for the mainly inductive loads to the procedure for the intermediate loads and vice-versa.

7. A centralized device for supply voltage control of a load with power factor correction condensers for lighting engineering applications according to claim 1 wherein said switching means of said array converter comprise electronic controlled switches.

8. A centralized device for supply voltage control of a load with power factor correction condensers for lighting engineering applications according to claim 7, wherein said switching means comprise a switch connected in series between the supply and the load and a switch connected in parallel to the load.

9. A centralized device for supply voltage control of a load with power factor correction condensers for lighting engineering applications according to claim 8, wherein each one of said switching means comprise at least two transistors connected to each other by means of their emitters and provided with protection diodes.

10. A centralized device for supply voltage control of a load with power factor correction condensers for lighting engineering applications according to claim 7 wherein said controlling and regulating means operate the control electrodes of said transistors through special signal outlets.

11. A centralized device for supply voltage control of a load with power factor correction condensers for lighting engineering applications according to claim 1, wherein said control and regulation device comprises an operation mode selection block and a deactivation control block, which receive information from the sensing means on the values reached by the load voltage and/or current and/or supply voltage, through special inlets of said control and regulation device.

12. A centralized device for supply voltage control of a load with power factor correction condensers for lighting engineering applications according to claim 11, wherein said operation mode selection block and deactivation control block control a switching logic block driving the plurality of outlets for controlling the switches.

13. A centralized device for supply voltage control of a load with power factor correction condensers for lighting engineering applications according to claim 12, wherein said switching logic block identifies the correct operation mode between the capacitive, inductive and intermediate modes, based on the measured quantities, supplying said information to the switching logic block.

14. A centralized device for supply voltage control of a load with power factor correction condensers for lighting engineering applications according to claim 12, wherein said block calculates the phase angle in correspondence to with deactivation of the switch has to be performed, based on the measured quantities, communicating it to said switching logic block.

15. A centralized device for supply voltage control of a load with power factor correction condensers for lighting engineering applications according to claim 13 wherein said switching logic block drives the activation and deactivation outlets for the transistors, respectively, based on the electric quantities, selected operation mode and upon deactivation of said bi-directional switch.

16. A method for controlling the supply voltage of a load with power factor correction condensers which provides for the use of a switch structure in the form of an array converter, said method controls said supply voltage operating a phase cut-off strategy, and provides for controlling and regulating means for the execution of said strategy, wherein, in order to actuate a switching of said switches, said method provides for:

receiving information on the values reached by the voltage and current of the load and supply voltage;

and automatically selecting the most correct operating procedure between a set of operating procedures.

17. A method for controlling the supply voltage of a load with power correction condensers according to claim 16, wherein said controlling and regulating means operate for obtaining a condition at the end of each regulation cycle such to ensure restart of the control strategy, as if in the instance of an ideal resistive load.

18. A method for controlling the supply voltage of a load with power correction condensers according to claim 17, wherein said controlling and regulating means operate a control according to a capacitive mode, maintaining the transistor that has not interrupted the supply current activated between two transistors forming the switch connected in series, so that as soon as the load voltage tends to become higher than the network voltage, a circuit will let the required current through between the load itself and the network.

19. A method for controlling the supply voltage of a load with power correction condensers according to claim 18, wherein said controlling and regulating means operate a control according to the inductive mode, activating the transistor connected in parallel to the load between the two transistors forming the switch, being able to conduct current in the direction of the load current, in order to maintain the voltage on the load around zero and let the device execute a connection again between the supply and the load at the subsequent passage for zero supply voltage, without a risk of voltage differences.

20. A method for controlling the supply voltage of a load with power correction condensers according to claim 19, wherein said controlling and regulating means activate the switch connected in series for conducting the supply current to the subsequent regulation cycle, and will subsequently deactivate the switch connected in parallel conducting the current of the load.

21. A method for controlling the supply voltage of a load with power correction condensers according to claim 20, wherein in the event of no transistors starting conduction during the control cycle, said control and regulation device will cause a forced passage to an intermediate operation mode for the subsequent cycle.

22. A method for controlling the supply voltage of a load with power correction condensers according to claim 20, wherein said intermediate mode operates analogously to the inductive mode;

however, deactivation of the switch connected in parallel occurs in advance compared to the passage for zero supply voltage, so that the loading voltage will equal the supply voltage during the subsequent regulation cycle.