EP1691587B1 - Method and apparatus to regulate and control a heating coil for lamps - Google Patents

Abstract

The method involves detecting an operational parameter of a coil (W1) that is arranged in a control loop. A manipulated variable (SG) is determined on the basis of the detected operational parameter by a heating controller (H). The coil and another coil (W2) that is arranged outside the control loop are controlled on the basis of the manipulated variable. The determined manipulated variable is transmitted to the coils via respective actuating units (S1, S2). The detected operational parameter of the former filament is transmitted to the heating controller. An independent claim is also included for a device for regulating and controlling a coil heating for a lamp i.e. fluorescent lamp.

Description

Technical area

The invention relates to a method and a device for controlling and controlling a filament heater for lamps, in particular fluorescent lamps.

State of the art

For lamps, especially fluorescent lamps, it is necessary to use coil heaters.

In Scripture US 5,798,614 is a method described with the precise Wendelheizung can be accomplished. This is achieved by determining the impedance of filaments in a period when neither a lamp current nor a heating current flows through the filaments.

In known Wendelheizungen it is common that these are unregulated. Particularly in the case of dimmable fluorescent lamps, in a process in which the light of the lamps is reduced by means of a dimmer, a reduction of the discharge current occurs. This results in that the heating of the coil is also reduced and it is therefore necessary to perform an external heating. In the known Wendelheizungen it is therefore necessary that depending on the number of lamps to be operated own ballasts have been developed because the heating was dependent on the number of lamps.

Presentation of the invention

It is therefore an object of the invention to provide a method and a device in which or in which the heating of coils can be performed with little effort.

This object is achieved by a method having the features of claim 1, and a device having the features of claim 6.

An inventive method is designed for controlling and controlling a filament heater for lamps. In particular, the filament heater for fluorescent lamps can be controlled and controlled by the method according to the invention. In a first step, an operating parameter of at least one first coil is detected. This first helix is arranged in a control loop. In a further step, a manipulated variable is determined as a function of the detected operating parameter. Depending on this manipulated variable, the first coil is regulated. Furthermore, a control of at least a second helix is carried out as a function of this manipulated variable, wherein the second helix is arranged outside the control loop. With the method according to the invention can be achieved that a low-cost heating of coils for lamps, in particular fluorescent lamps, can be realized. It can thus be achieved that an operating parameter is detected only by a single helix and from the obtained information of the operating parameter a manipulated variable is determined, which is used on the one hand to control the first helix and to control another helix by means of this manipulated variable. Thus, for the auxiliary heating, it is only necessary to obtain information about the heating behavior of this coil from a coil in order to be able to carry out a corresponding change in the heating of both coils with little effort. All coils are thus always operated optimally.

Advantageously, the detection of the operating parameter and the determination of the manipulated variable is performed independently of the number of filaments and the lamps electrically connected to the filaments. The heating of the filaments, in particular the controlled heating of the filaments, is independent of the number of connected filaments or the connected lamps. The number of entrained coils thus has no influence on the control. It can thus be achieved that, by means of the information of an operating parameter of only one single helix, a manipulated variable is determined by means of which the heating of a relatively large number of helices, which are all connected outside the control loop, is controlled.

It can be provided that the heating power of this controlled coil is detected as the operating parameter of the controlled coil. It may further be provided that the specific manipulated variable is transmitted via a first actuator to the first coil and a second actuator to the second coil. In an advantageous embodiment, the detected operating parameter of the first coil is transmitted to a heating controller and determines the manipulated variable by means of the heating controller.

A device according to the invention for controlling and controlling a filament heater for a lamp, in particular for a fluorescent lamp, has a control loop. In this control loop, a first coil, means for detecting an operating parameter of this first coil and means for generating a manipulated variable for controlling this first coil, connected. Furthermore, the device according to the invention comprises a second coil, which is arranged outside the control loop or is connected outside the control loop into the device. This second helix can be controlled by means of the control variable determined by the control loop. By means of the invention, a device can be provided which allows low-cost auxiliary heating of the filaments for a lamp.

Preferably, the control loop comprises a detection member for detecting an operating parameter of the first coil and a first actuator, wherein the first actuator and the detection member are electrically connected to the first coil. In an advantageous embodiment, a heating controller is connected in the control loop between the detection member and the first actuator. Furthermore, it can be provided that the at least second coil is electrically connected to the first or a second actuator. It can also be provided that the heating controller is electrically connected to the first and second actuator.

It proves to be particularly preferred if the device for controlling and controlling a helical heating or an advantageous embodiment thereof as a ballast for lamps is used. Particularly suitable is the use as a dimmable ballast for lamps, especially for fluorescent lamps.

Brief description of the drawings

An embodiment of the invention will be explained in more detail with reference to a schematic drawing. The single FIGURE shows a device according to the invention for controlling and controlling a filament heater for fluorescent lamps, which is used as a ballast for fluorescent lamps.

Preferred embodiment of the invention

FIG. 1 shows a first coil W1, which serves to heat a lamp, which in the exemplary embodiment is designed as a fluorescent lamp L1. The coil W1 is electrically connected at a first end to the fluorescent lamp L1. Furthermore, the first coil W1 is electrically connected at a second end to a first actuator S1. Furthermore, a detection element E is shown in FIG. The detection element E is designed in the exemplary embodiment such that an operating parameter of the first coil W1 can be detected. The detection element E is electrically connected to a heating controller H. Furthermore, the heating controller H is electrically connected in the exemplary embodiment with the actuator S1. In the embodiment according to FIG. 1, the control loop is formed by the first coil W1, the detection element E, the heating controller H and the first actuator S1 as the essential elements.

As can further be seen in the exemplary embodiment according to FIG. 1, a second coil W2 is electrically connected to the fluorescent lamp L1 at a first end and to a second actuator S2 at a second end. Further, coils W3 to Wn are electrically connected to the second actuator S2 and lamps L2 to Ln. In the embodiment, an electrical connection between the heating controller H and the second actuator S2 is also formed.

It can also be provided that the second actuator S2 is not present and the coils W2 to Wn are electrically connected to the first actuator S1. It should be noted that the coils W2 to Wn are arranged outside the control loop or are connected outside the control loop into the device according to the invention, as shown in FIG.

It can also be provided that the detection element E is electrically connected to another coil, for example to the coil W2. In this case, the circuit arrangement of the device would have to be designed such that, instead of the first coil W1, the second coil W2 is arranged in the control loop. But it can also be provided that two or more coils are electrically connected to the detection element E and are connected in a corresponding control loop. In such an embodiment, the operating parameters of two or more coils are detected and determined from the corresponding information of these operating parameters of the plurality of coils a corresponding control variable by the heating controller H. The actuator S1 and the actuator S2 are formed in the embodiment as voltage sources with duty cycle change.

Below will be discussed in more detail on the inventive method for controlling and controlling the coil heating. An operating parameter of the first coil W1, which in the exemplary embodiment is the heating power of this first coil W1, is detected by means of the detection element E. The detected heating power is transmitted as controlled variable R to the heating controller H. By means of the heating controller H a corresponding performance recording is performed. Furthermore, the heating controller H determines, as a function of the control variable R obtained, a manipulated variable SG, which is transmitted to the first actuator S1 and to the second actuator S2. The manipulated variable SG is a signal which includes a duty cycle as information. By the first actuator S1 and the second actuator S2 are formed as voltage sources with duty cycle change in the embodiment, the duty cycle to the actuators S1 and S2 can be changed by means of the transmitted manipulated variable SG. By transmitting this manipulated variable SG to the first actuator S1 is a duty cycle change and due to the duty cycle of the voltage source or the first actuator S1, a control of the first helix W1 is performed. Furthermore, by transferring this manipulated variable SG to the second actuator S2 or to this second voltage source with duty cycle change, a change in this duty cycle is also achieved there. Accordingly, the coils W2 to Wn are controlled by means of the second actuator S2. It is thereby achieved that by detecting an operating parameter of a single helix, in the embodiment of the first helix W1, a control variable R and depending on a manipulated variable SG is generated, on the one hand controls this first helix W1 and on the other hand additional helices W2 to Wn , which are not connected in the control loop, but in the device are arranged or interconnected, are controlled.

The regulation of the heating of coils, which is necessary in particular for dimmable fluorescent lamps, since when dimming a discharge current reduction and the resulting reduction of the heating of the coils occurs according to the invention with reference to a single helix W1. However, it can also be provided that the control of the heating with at least two coils, which are connected in the control loop, are performed. By the manipulated variable SG is also supplied to the actuators, which are not arranged in the control loop, the heating of those coils, which are arranged outside the control loop in the device, carried along according to the regulated coils. It should be noted that a change in the number of lamps in Figure 1 is independent of the control of the heater. This means that even if the number of lamps is changed, for example, increased, the control operation thereof is not affected. A change in the number of lamps thus leads to no change in the heating. All coils can be operated optimally, because the number of entrained coils has no influence on the control. The principle according to the invention is independent of the nature of the resonant circuit (s) or independent of the type of discharge current generation. The inventive device of a mixed-controlled / controlled filament heating is preferably used as a dimmable ballast for fluorescent lamps.

Claims (12)

1. Method for the closed-loop and open-loop control of filament heating for lamps, in particular fluorescent lamps, which has the following steps:

   a) detection of an operational parameter of at least one first filament (W1) arranged in a control loop;

   b) determination of a manipulated variable (SG) on the basis of the detected operational parameter;

   c) closed-loop control of the first filament (W1):
   the method being characterized by the following step:

   d) open-loop control of an at least second filament (W2 to Wn) arranged outside the control loop. on the basis of the manipulated variable (SG).
2. Method according to Claim 1,
   characterized
   in that the detection of the operational parameter and the determination of the manipulated variable (SG) are carried out independently of the number of filaments (W1 to Wn) and of lamps (L1 to Ln) which are electrically connected to the filaments (W1 to Wn).
3. Method according to Claim 1 or 2,
   characterized
   in that the heating power of the first filament (W1) is detected as the operational parameter.
4. Method according to one of the preceding claims,
   characterized
   in that the determined manipulated variable (SG) is transmitted to the first filament (W1) via a first actuating element (S1) and to the second filament (W2) via a second actuating element (S2).
5. Method according to one of the preceding claims,
   characterized
   in that the detected operational parameter of the first filament (W1) is transmitted to a heating controller (H), and the manipulated variable (SG) is determined by means of the heating controller.
6. Apparatus for the closed-loop and open-loop control of filament heating for a lamp, in particular for a fluorescent lamp, having

   - a control loop which has at least one first filament (W1), means for detecting an operational parameter of the first filament (W1) and means for generating a manipulated variable (SG) for the closed-loop control of the first filament (W1); and

   - the apparatus being characterized in that an at least second filament (W2 to Wn), which is connected into the apparatus outside the control loop and can be subjected to open-loop control by means of the manipulated variable (SG) determined by the control loop.
7. Apparatus according to Claim 6,
   characterized
   in that the control loop has a detection element (E) for the purpose of detecting an operational parameter of the first filament (W1) and a first actuating element (S1), the first actuating element (S1) and the detection element (E) being electrically connected to the first filament (W1).
8. Apparatus according to Claim 7,
   characterized
   in that a heating controller (H) is connected into the control loop between the detection element (E) and the first actuating element (S1).
9. Apparatus according to one of the preceding Claims 7 to 8,
   characterized
   in that the at least second filament (W2 to Wn) is electrically connected to the first actuating element (S1) or a second actuating element (S2).
10. Apparatus according to Claims 8 and 9,
    characterized
    in that the heating controller (H) is electrically connected to the first actuating element (S1) and the second actuating element (S2).
11. Apparatus according to one of Claims 7 to 10,
    characterized
    in that the first actuating element (S1) and the second actuating element (S2), possibly provided, are in the form of voltage sources with duty ratio change.
12. Use of the apparatus for the closed-loop and open-loop control of filament heating according to one of the preceding Claims 6 to 11 as a ballast, in particular as a dimmable ballast for lamps, in particular for fluorescent lamps.

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