JPH0242036Y2 - - Google Patents

Description

[Detailed description of the invention] The invention is based on two signals in which one input signal always occurs earlier in time than the other input signal.
This invention relates to an output circuit for a static relay that generates an operating signal under an AND condition.

Some static relays employ a phase angle measuring circuit that responds when the phase angles of a plurality of electrical quantities meet predetermined conditions as a determination circuit. An example of an output circuit of such a static relay is shown in FIG. In FIG. 1, input circuits 1 and 2 each receive two different signals, one of which always occurs earlier in time than the other, as follows:
The respective detection circuits 1a and 2a detect signals as shown in FIG. 2A and convert them into rectangular shock waves as shown in FIG. input
A signal continuation circuit 1b that extends the _tR time and makes it continuous;
2b, and the respective outputs of the serialization circuits 1b and 2b are given to the AND circuit 3. In FIG. 2, the horizontal axis is time T, and the vertical axis is the signal input/output waveform (the horizontal axes in the waveform diagrams below are all time T). Now, when a signal _S1 as shown in FIG. 2A is given to the input circuit 1, the output of the detection circuit 1a is as shown in FIG.
The shock wave becomes a rectangular shock wave as shown in Figure C, and is further extended by the continuity circuit 1b for the time t _R to become a continuous wave as shown in Figure C. Further, when a signal S ₂ having a similar shape and size and having a phase shift with the signal S ₁ is applied to the input circuit 2, the output of the detection circuit 2a becomes a rectangular shock wave as shown in FIG.
As a result, the wave is extended by the time _tR , resulting in a continuous wave as shown in Figure E. Two input circuits 1 and 2 like this
When a continuous wave output of is given to the AND circuit, this
Only when the two inputs shown in C and E in the same figure are applied to the AND circuit 3 at the same time, an output as shown in F in the same figure is generated and the relay is operated. By the way, if, as shown in FIG. 3, the output of the detection circuit 1a is A in the figure for time T, the output of the continuation circuit 1b is B in the figure, and the output of the detection circuit 2a is C in the figure, The output of circuit 2b is as shown in figure D, and even if input circuit 1 becomes inactive at time t ₁ , its continuous output is still continuous, so at the same time t ₁ , input circuit 1 2 becomes the operating condition, the AND circuit 3 generates an output as shown in FIG. 2E, which causes the relay to malfunction. To prevent such malfunction, AND
For example, by providing a time delay circuit on the output side of circuit 3,
If you make the output occur after t ₂ , t ₁
-t Although it is possible to prevent malfunctions between ₂ o'clock, this method has the disadvantage of causing a time delay even when it is important to operate.

The object of the present invention is to eliminate the above-mentioned drawbacks and provide an output circuit for a static relay that is free from malfunctions.

The purpose of this is to provide an output circuit for a static relay that outputs an operational output based on the AND condition of two input signals in which one input signal always occurs earlier than the other input signal. The signal is applied directly to the AND circuit, the other input signal is applied to the AND circuit via a first signal continuation circuit, and the output of the AND circuit is applied to the second signal continuation circuit. This is achieved by outputting an operational output from the second signal continuity circuit. That is, according to the present invention, one input circuit is provided with only a circuit for detecting a signal, and the other input circuit is provided with a detection circuit and a signal continuation circuit, so that as the first signal becomes longer, other signals that are subsequently applied are This output circuit is designed to prevent errors from interfering with signals and to provide an output signal continuity circuit next to the AND circuit to ensure reliable operation of the relay.

Embodiments of the present invention will be described in detail below with reference to the drawings. In FIG. 4, in the input circuit 1, the output of the detection circuit 1a is directly connected to the AND circuit 3. In addition, in the input circuit 2, a signal continuation circuit 2b is connected to the output side of the detection circuit 2a, and this output side is connected to the output side of the detection circuit 2a.
Connected to AND circuit 3. The output of the AND circuit 3 is further connected to an output signal continuation circuit 4. Therefore, when a signal S ₁ is applied to the input circuit 1, this signal S ₁ is applied to the AND circuit 3 as a rectangular shock wave as shown in FIG. 5A. Furthermore, when the input circuit 2 is given a signal S ₂ that is out of phase with the signal S ₁ , the output of the detection circuit 2a becomes a square shock wave as shown in Figure B, and the output of the continuation circuit 2b to which this square shock wave is given is , is applied to the AND circuit 3 as a continuous wave as shown in FIG. In this way, only when both the outputs shown in FIG. 2A and FIG. 3C are simultaneously applied to the input side of the AND circuit 3, an output as shown in FIG. This output is then given to the output signal continuation circuit 4 to obtain the required operational output as shown in FIG. In the circuit shown in Fig. 4, even if
The mutual phase relationship between the two signals S ₁ and _{S 2} caused a malfunction in the conventional circuit as shown in FIG. Even if the signal of the detection circuit _2a due to the signal S2 of the input circuit 2 is as shown in Figure B, the output of the continuation circuit _2b generated by this signal S2 is as shown in Figure C. becomes, AND
The circuit 3 is provided with an output shown in A of the same figure and an output shown in C of the same figure. In this state, the outputs of the input circuits 1 and 2 are not simultaneously applied to the AND circuit 3, so the AND circuit 3 does not generate an output as shown in FIG. Naturally, this static relay does not work. In other words, the malfunction shown in FIG. 3 does not occur.

As described above, the output circuit of the static relay according to the present invention detects two signals in which one input signal always occurs earlier than the other input signal, and one outputs a rectangular shock wave while the other outputs a continuous wave. As a wave, malfunctions are eliminated by finding the AND condition, and the output is made continuous after finding the AND condition. Therefore, a time limit circuit for preventing malfunction is not required, and an excellent relay that is inexpensive and highly reliable can be provided.

[Brief explanation of the drawing]

Figure 1 is a block diagram showing an example of the output circuit of a conventional static relay, Figures 2 and 3 are input/output signal waveforms of the output circuit shown in Figure 1, and Figure 4 is a static relay according to the present invention. 5 and 6 are block diagrams showing an embodiment of the output circuit of FIG.
3 is an input/output signal waveform showing the operation of the output circuit shown in the figure. 1b, 2b...Signal continuity circuit, 3...AND
Circuit, 4...Output signal continuity circuit.

Claims (1)

[Claims for Utility Model Registration] An output circuit for a static relay that outputs an operational output based on the logical product condition of two input signals in which one input signal always occurs earlier in time than the other input signal. The one input signal is applied directly to the AND circuit, the other input signal is applied to the AND circuit via a first signal continuation circuit, and the output of the AND circuit is applied to the second signal. An output circuit for a static relay, characterized in that an operating output is output from this second signal continuity circuit in addition to the continuity circuit.