KR20160073225A - Universal transformer design for PSR(Primary Side Regulation) - Google Patents

Abstract

The present invention relates to a primary side regulation (PSR) transformer which can be optimally applied well even in any type of a PSR type LED driver IC. The PSR transformer can be manufactured with a winding order to manufacture a PSR flyback topology transformer described in figure 6.

Description

PSR (Primary Side Regulation) Transformer {Universal transformer design for PSR (Primary Side Regulation)}

The present invention relates to a PSR (Primary Side Regulation) transformer which can be optimally applied to any kind of PSR Type LED Driver IC.

Low Power LED Lamp Transformer design method is very important in using PSR flyback topology which is widely used in power consumption. Particularly, in this transformer design, the LED lamp driver IC and the transformer design method must match.

However, the choice of the PSR LED Driver IC is especially important for this T8 / T10 LED straight tube lamp (K20001) and the E26 / E27 LED Bulb lamp (insulation type) for this AC power converter. However, when designing the transformer correctly by looking at the IC manufacturer Application notes, there is a problem that even it does not work properly. In addition, the LED lamp is mainly driven by the CC (Constant Current) method.

However, the LED lamp driver IC from the current IC manufacturer is designed as an LED exclusive PSR method, and the application product operates differently from the IC in other fields. In order to develop a power source that meets the characteristics of an LED lamp using a commercially available DC electronic load, a DC electronic load capable of holding a CV is required. Normally, we use an electronic rod of a product called PLZ-303W from KIKUSUI of Japan.

However, there is a problem in designing a precisely insulated PSR flyback transformer using this. There are various problems such as instability of operation, low power factor, IC shut down problem, and a problem of decrease of LED output drive current at low voltage input in case of universal ac input voltage. This is a major problem in flyback transformer design.

There are so many transformer designs proposed by IC vendors in Application notes that they are specialized in a specific part of the application product. Therefore, there is a problem that many trial and error must be repeated to produce a certain product.

In fact, even if IC manufacturers correctly understand the concept of primary side regulation (PSR) flyback topology, it is very difficult to solve this problem if the basic concept of PSR flyback transformer design is not accurate.

To solve this problem, I would like to suggest a general design method of a PSR transformer used in LED lighting.

An embodiment of the present invention is to provide a PSR (Primary Side Regulation) transformer that can be optimally applied to any kind of PSR Type LED Driver IC.

According to the PSR (Primary Side Regulation) transformer according to the embodiment of the present invention, the operation control method of the PSR LED lamp driver IC can be described by referring to the graph shown in FIG.

Here is the general operating waveform of the flyback topology of the IC used in the PSR Solution of all LED Lamps. Usually PSR Solution should operate in DCM, CRM (TM) mode.

In this mode, the Transformer design is usually about 50% important for good operation.

In the PSR solution, the transformer must play a role in delivering both power supply and control information.

Compared to the existing SSR (Secondary side regulation) solution, SSR has additional photo coupler, shunt regulator, compensation circuit, voltage sensing circuit, etc. In the PSR method, output voltage sensing only excludes output voltage sensing. Control information is passed through the Transformer.

Thus, coupling is very important between the primary and secondary sides, the Vcc winding side of the primary side. In particular, in the coupling, the problematic leakage inductance should be minimized.

The way in which the winding is placed in the least leaking inductance is solved by a transformer winding in the manner described in the table above. Coupling To be strong, the distance between the different windings should be close. However, the leakage inductance must be designed in the smallest way.

Through the method shown in Table 1 above, it can be seen that the coupling between the auxiliary winding on the primary side and the winding on the secondary side occurs very strongly.

Also, Table 1 above shows the Flyback transformer winding structure that solves the EMI problem. This provides the most complete implementation of EMI problems and PSR flyback solutions. This can be expressed as shown in FIG.

The PSR (Primary Side Regulation) transformer according to the present invention has the following effect.

By using the flyback transformer winding according to the winding method described above, it will be the most suitable solution for various kinds of PSR LED lamp driver IC.

This method can be applied to external T8 / T10 LED Converter board of AC power converter and it is the most suitable transformer winding method for E26 / E27 LED Bulb. As a result of examination, no problem has been found yet.

As a result of applying this method to the PSR LED lamp driver IC, there was no problem in LED lamp operation control, and EMI problem did not occur.

Designing the flyback transformer winding in the above manner did not cause any problems with any transformer. Compared with transformer windings made in other ways, it has excellent performance in terms of operation, environmental reliability, and operational stability.

Even if the circuit design of the LED lamp driver IC is perfect, if the transformer design is inadequate, it may cause various problems such as operation stability, EMI problem, electric safety specification problem, and so on. , We have been able to develop a stable LED converter board that fits perfectly with the applications described above.

1 is a waveform diagram of a PSR solution according to the present invention;
2 is a structural view of a transformer winding according to the present invention.
3 is a structural view of a transformer winding according to the present invention. (Primary winding method)
4 is a structural view of a transformer winding according to the present invention. (Vcc winding method - reduce the influence.)
5 is a structural view of a transformer winding according to the present invention.
6 is a circuit diagram of a transformer winding according to the present invention.
7 is a structural view of a transformer winding according to the present invention.

Hereinafter, the present invention will be described in more detail with reference to the drawings.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings and accompanying drawings, but the present invention is not limited to or limited by the embodiments.

As used herein, terms used in the present invention are selected from general terms that are widely used in the present invention while taking into account the functions of the present invention, but these may vary depending on the intention or custom of a person skilled in the art or the emergence of new technologies. In addition, in certain cases, there may be a term arbitrarily selected by the applicant, in which case the meaning thereof will be described in the description of the corresponding invention. Therefore, it is intended that the terminology used herein should be interpreted based on the meaning of the term rather than on the name of the term, and on the entire contents of the specification.

PSR Flyback transformer There are many different winding methods for winding method. And a transformer winding method for ensuring the most stable control and operation reliability among them. Here, it is assumed that the circuit system other than the transformer is designed optimally.

The specific winding method and structure of the windings are described below, assuming that the LED lamp driver ICs are all on the primary side as a basic assumption.

The structure of the transformer winding will be described with reference to FIGS. 3 to 5 as follows.

Part # 1: Primary winding method - Transformer (see Figure 3)

1) Primary winding sandwich winding method

2) □ 3mm Barrier tape.

3) ● Transformer winding start point

: PET 절연 테이프 (보통 0.025, 0.05mm 두께)4)

: PET insulation tape (usually 0.025, 0.05mm thick)

5) winding order: NP / 2 => NP / 2 => Ns => Na

6) └┘ transformer bobbin outer wall

Part # 2: Winding sequence to reduce Vcc variation (See Fig. 4)

Basic assumption: Assuming that the secondary output appears in two forms.

If the primary side winding and the Vcc winding are arranged distantly from each other, the strength of the coupling weakens each other.

In order to minimize the influence of changes in the driving current / driving voltage of the primary windings, the distance from the primary windings can be maximized.

If you understand exactly how the transformer works, you can follow this winding sequence.

Part # 3: A sequence of sandwich windings with two secondary outputs (see Figure 5)

Basic assumption: Assuming that the secondary output appears in two forms.

A method for reducing the leakage inductance of the primary and secondary sides.

This is a method for reducing the winding loss in terms of energy transfer between the primary and secondary sides

The disadvantage is that it is not good in terms of EMI. In the PSR flyback topology, power transfer and control information are transmitted through the switching transformer. The sandwich winding method is the best way to express this. Particularly, in the PSR flyback topology method, the coupling strength between the primary side and the secondary side winding and the auxiliary winding must be very strong, and at the same time, the strength of the coupling between the primary side winding and the auxiliary side winding is higher than the coupling strength between the primary side and the secondary side We have to be weaker. At this time, the best method is the way I present.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail.

1. PSR Flyback topology The habit of knowing exactly what a concept is is very important.

1) It is necessary to understand the basic operation of PSR accurately

2) Flyback needs to understand the concept of topology accurately

3) Understand output voltage / current control meaning of PSR flyback topology

4) It is necessary to understand how the concept of PSR flyback topology differs from other application concepts in LED lighting.

2. Understand the knowledge of Transformer design and its countermeasures (see Figure 6)

1) ● Positive potential at the start of the winding, and potential at the finish.

2) The operation of the PSR flyback topology transformer must be phase-wise as shown in the figure above.

3) The winding order of the windings shall be the same in both directions.

4) It is an expression indicating relative potential at a certain reference point. All PSR flyback transformers must be of this potential type at the time of operation. If the potential indication of the AC waveform and the current polarity indication are changed, there is a problem that the output load is not received.

3. Production of PSR Flyback topology transformer and completion of measures to solve problems - Completion of product (see Fig. 7)

1) Completion of final Transformer production method

2) PSR topology transformer made in order of winding => The control information is transmitted accurately through the transformer manufactured in this order, so that the feedback is correct and the system is stable.

3) This is a good winding method for EMI measures.

The PSR flyback transformer is manufactured immediately in the order described above, and it is the most suitable for all PSR LED lamp driver IC, and it is the correct operation. However, PSR LED Lamp Driver accurately understands all operation and operation limit situation of IC, and understand the Application notes and test it by making this transformer in the whole system and operate it in the correct way.

In addition, it is the best solution for lamps such as lamp (1200mm, 600mm), T5 LED straight tube lamp (1200mm, 600mm) and E26 / E27 LED bulb etc. which are external power source of AC power converter external T8 / do.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be construed as limiting the scope of the invention as defined by the appended claims. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention.

Claims (3)

A primary side regulation (PSR) transformer having a winding sequence for fabricating the PSR flyback topology transformer shown in FIG. 6; The method according to claim 1,
A PSR (Primary Side Regulation) transformer characterized by using a shielding method o to solve the EMI problem in the PSR flyback transformer. The method according to claim 1,
A PSR (Primary Side Regulation) transformer characterized by using a sandwich winding method to reduce the leakage inductance in the PSR flyback transformer and to adjust the coupling degree and the strength of the coupling between the windings.

Images