JPH0418792B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement in a transformer winding polarity determining circuit that determines the polarity of a transformer winding.

It is desirable that the transformer winding polarity determining circuit does not output erroneous polarity determining data, but outputs data indicating this when the winding is broken.

[Conventional technology]

Fig. 5 is a block diagram of a conventional transformer winding polarity discrimination circuit, and Fig. 6 is a time chart of waveforms of various parts of the circuit in Fig. 5, and A to D correspond to points a to d in Fig. 5. . FIG. 7 is a time chart of waveforms at various parts when the winding of the transformer T shown in FIG. 5 is broken.

In the figure, 1 is an AC oscillator, 2 is a 1-pulse oscillator,
3 and 4 are comparators, 5 is an exclusive OR circuit, 6 is a flip-flop (hereinafter referred to as FF), and T is a transformer.

In FIG. 5, in order to determine the polarity of the winding of the transformer T, an AC voltage as shown in FIG. 6. A waveform output as shown in FIG. 6B is obtained and input to the exclusive OR circuit 5.

On the other hand, if the winding polarities are the same, the secondary side of the transformer T outputs a voltage with the same waveform as in Figure 6A, and the comparator 4 outputs a voltage with the same waveform as in Figure 6B. If the polarity of the winding of T is reversed, an output with a waveform as shown in FIG. 6C is obtained from the exclusive OR circuit 5.
Enter.

Therefore, if the polarities of the windings are the same, the exclusive OR circuit 5 continuously outputs a 0 level, and if the polarities are reversed, a 1 level is continuously output and input to the D terminal of the FF6. do.

The CLK terminal of FF6 receives a pulse as shown in Fig. 6D from the 1-pulse oscillator 2 which outputs 1 pulse at approximately the center of the waveform shown in Fig. 6A, and the pulse shown in Fig. 6D is input to the D terminal. Since the input level is struck, FF6 outputs level 0 if the polarities of the windings are the same, and level 1 if the polarities are reversed.

This means that the output pulse of the 1-pulse oscillator 2 is
Even if it is located in the center of the + voltage in Figure 6A, as in case A in Figure D, or in the middle of the - voltage in Figure 6A, as shown in Figure 6B, the same level of data is output from FF6. In particular, the pulse of the 1-pulse oscillator 2 can be generated without being aware of the positive and negative sides of the AC voltage.
The polarity of the winding is determined.

[Problem that the invention seeks to solve]

However, if the winding of the transformer T is disconnected, the 7th
A voltage as shown in Figure B is induced, the output of comparator 4 is as shown in Figure 7C, and the output of comparator 3 is as shown in Figure 7A and the same as Figure 6B, so the exclusive logic The output of the sum circuit 5 is 0 level when the output of the comparator 3 is C, and 1 level when the output is D.
Input to the D terminal of FF6.

Therefore, when the input to the D terminal of FF6 is struck with the output of the 1-pulse oscillator 2, and when the input to the D terminal of FF6 is struck with the pulse shown in Fig. 7A, the output of FF6 is at 0 level and the polarity of the winding of the transformer T is determined. are determined to be the same, and when struck with the pulse shown in FIG. 7B, the output of FF6 is determined to be 1 level and the polarity of the winding is reversed.

That is, there are problems in that winding breakage cannot be determined and the polarity of the winding can be determined in two ways even though the transformer is the same.

[Means for solving problems]

The above problem is solved by applying a pulse of one and a half cycles to the primary side of the transformer, and inputting this pulse to the exclusive OR circuit via a comparator that compares this pulse with the pulse generated on the secondary side with the ground level. input the output to three flip-flops, and input the output to three flip-flops.
At the clock terminal of each of the two flip-flops,
This problem is solved by the transformer winding polarity determining circuit of the present invention, which inputs each sampling pulse of each half cycle of the one and a half cycle pulses and determines the polarity of the transformer winding based on the outputs of the three flip-flops.

[Effect]

According to the present invention, if the transformer is not disconnected, the outputs of the three FFs are all 1 level or 0 level depending on the winding polarity, and if the transformer is disconnected, 1 level and 0 level are output. Therefore, it is possible to determine whether the winding of the transformer is broken or not, and there is no need to output erroneous polarity determination data.

〔Example〕

Fig. 1 is a block diagram of a transformer winding polarity discrimination circuit according to an embodiment of the present invention, and Fig. 2 is a time chart of waveforms of various parts of the circuit shown in Fig. 1, A, C, E, G to J.
correspond to points a, c, e, g to j in FIG. 3 and 4 are time charts of waveforms at various parts when the winding of the transformer T in FIG. 1 is broken.

In the figure, 7 is a one-and-a-half cycle pulse oscillator, and 8 is a 1-cycle pulse oscillator.
Sampling clock generator with pulses of half a cycle; 9 is a counter; 10 is a decoder; 11 to 13;
14 is an FF, 14 is an AND circuit, and 15 and 16 are NOR circuits, and the same reference numerals indicate the same functions throughout the drawings.

To explain the operation of the circuit shown in Fig. 1, the one and a half cycle pulse oscillator 7 outputs positive/negative/positive or negative/positive/negative pulses as shown in Fig. 2 A or B, which are applied to the primary side of the transformer T and compared. 3 and the output as shown in FIG. 2 C or D is input to the exclusive OR circuit 5.

On the other hand, from the secondary side of the transformer T, if the winding polarities are the same, a pulse with the same waveform as in Figure 2 A or B will be output, and if the polarity is reversed, a pulse with the waveform as in Figure 2 B or A will be output. , is input to the comparator 4, and from this output, if the winding polarities are the same, it will be C or D in Figure 2.
If the polarity of the windings is the same, the pulse of D or C in FIG. 2 is output and input to the exclusive OR circuit 5. 0 as shown in Figure 2E.
The level is output, and if the reverse is the case, the 1 level is output and input to the D terminals of FFs 11, 12, and 13.

On the other hand, the output as shown in FIG. 2G from the sampling clock generator 8, which generates a sampling clock for every half cycle of one half pulse, is input to the counter 9, where it is counted, and the count value is sent to the decoder. 10, and the output of the decoder 10 outputs pulses separated into one pulse as shown in FIG. 2 H, I, J.
Input to CLK terminals 1, 12, 13 and hit the level input to D terminal, so FF11, 1
The outputs of 2 and 13 are all 0 level if the polarities of the windings of the transformer T are the same, and are all 1 level if the polarities are reversed.

Therefore, if the polarities of the windings are the same, the output terminal _A1 of the NOR circuit 15 is at the 1 level, and the output terminal _A0 of the AND circuit 14 and the output terminal _A2 of the NOR circuit 16 are at the 0 level. , if it is the opposite, the terminal A ₀ will be at 1 level and the others will be at 0 level, and the polarity of the winding of the transformer T can be determined.

Here, if the winding of the transformer T is disconnected, a voltage as shown in Figure 3B will be induced on the secondary side of the transformer T by induction from the commercial power supply, and the voltage as shown in Figure 3B will be induced on the primary side of the transformer T. Assuming that a pulse of one and a half cycles as shown in Figure 3A is input,
During this time, the output of comparator 4 is at level 1, so
The output of the exclusive OR circuit 5 becomes 0, 1, 0 level as shown in FIG. 3C, and FF11, 12, 13
and this level is input to the second output from the decoder 10.
When struck with the pulses shown in Figures H, I, and J, FF11,
The outputs of terminals 12 and 13 are at 0, 1, 0 level, the output terminal _A0 of AND circuit 14 is at 0 level, the output terminal _A1 of NOR circuit 15 is also at 0 level, and the output terminal _A2 of NOR circuit 16 is at 0 level. It becomes level 1 and notifies winding breakage of the transformer T, but does not discriminate the winding polarity, so the winding breakage can be recognized and the polarity will not be determined incorrectly.

Note that the zero cross point of the voltage induced from the commercial power supply as shown in Figure 4B is 1 as shown in Figure 4A.
When the cycle and half pulse match, the outputs of comparators 4 and 3 become as shown in FIG. 4C and D, and the output of exclusive OR circuit 5 becomes 0, 0, 1 as shown in E, or F As shown in the figure, it becomes 1, 0, 1, but since 0 and 1 levels are always output, the terminal
_A2 is at 1 level, the other terminals are at 0 level, a disconnection is detected, and the polarity is not determined.

However, if the output of the oscillator 7 is a one-cycle pulse, the output of the exclusive OR circuit 5 may become 0, 0, and in this case, a disconnection is not detected and the polarity is incorrectly determined. Therefore, the output of the oscillator 7 is assumed to be one and a half cycles.

〔Effect of the invention〕

As described in detail above, according to the present invention, there is an effect that disconnection of the winding of the transformer can be detected and that data for determining the polarity of the wrong winding is not output.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a transformer winding polarity discrimination circuit according to an embodiment of the present invention, FIG. 2 is a time chart of waveforms of various parts of the circuit of FIG. 1, and FIG.
5 is a block diagram of a conventional transformer winding polarity determination circuit. FIG. 6 is a time chart of waveforms at various parts of the circuit in FIG. 5. FIG. 7 is a time chart of waveforms at various parts when the winding of the transformer T shown in FIG. 5 is broken. In the figure, 1 is an AC oscillator, 2 is a 1-pulse oscillator, 3 and 4 are comparators, 5 is an exclusive OR circuit,
6, 11, 12, 13 are flip-flops, 7 is a one and a half cycle pulse oscillator, 8 is a sampling clock generator, 9 is a counter, 10 is a decoder, 4 is an AND circuit, 15, 16 is a NOR circuit, T
indicates a transformer.

Claims (1)

[Claims] 1 A pulse of one and a half cycles is applied to the primary side of the transformer, and this pulse and the pulse generated on the secondary side are input to an exclusive OR circuit via a comparator that compares each with the ground level, and its output is is input to three flip-flops, and each sampling pulse of each half cycle of the one and a half cycle pulses is input to the clock terminal of each of the three flip-flops, and the transformer winding is controlled by the outputs of the three flip-flops. A transformer winding polarity discrimination circuit characterized in that it discriminates polarity.