JPS6048764B2 - phase control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a phase control device that controls the firing angle of a thyristor using detection signals output from sensors such as temperature and pressure.

FIG. 1 is a block diagram showing an example of a conventional device of this kind. In the figure, 1 is an AC power supply, 2 is a clock pulse generator that generates clock pulses at a constant phase of the voltage of the AC power supply 1, and 3 is a block diagram showing an example of a conventional device of this type. The sensor section 4a is an input terminal from the sensor section 3.

A thyristor firing signal with a phase determined according to the detection signal input to the input terminal (IN) is sent from the clock pulse generator 2 to the input terminal (IN).
, the output terminal OU is synchronized with the clock pulse input to the
The firing angle determining section that outputs to T, the part 9 surrounded by dotted lines is the switching transistor 5, resistor 6, and pulse transformer 7
and a diode 8; 10 is a reverse three-terminal thyristor whose ignition is controlled by a thyristor trigger part 9; and 11 is a load whose supplied power is adjusted by phase control. FIG. 2 is a waveform diagram showing an example of waveforms in the main parts of the device shown in FIG. 1, and the operation of the device shown in FIG. 1 will be explained with reference to FIG.

In Figure 2, waveform A is a full-wave rectified waveform of AC power supply voltage.
The waveform opening is a clock pulse obtained by detecting the zero point crossing of waveform A, and its period is indicated as T (half cycle of AC power supply voltage).

Waveform C is a thyristor firing signal (generally a control pulse signal) whose delay amount t from the clock pulse (waveform A) is determined according to the input signal from the sensor section 3. Moreover, waveform 2 shows an AC voltage waveform (phase control waveform) applied to the load 11. Since the method of determining the delay amount t in the firing angle determination unit 4a based on the input signal from the sensor unit 3 and generating the thyristor firing signal of waveform C from the waveform opening is well known, a description thereof will be omitted. do.

According to this thyristor firing signal, the thyristor trigger section 9
ignites the bidirectional three-terminal thyristor 10 and controls the energization to the load 11 (see FIG. 2C). As explained above, the conventional phase control device is configured such that the firing angle determining section 4a always outputs a thyristor firing signal every half cycle T of the AC power supply voltage.

However, depending on the type of sensor unit 3, the detection signal may change slowly, and in such cases, it is not necessary to always determine the firing angle for every half cycle of the AC power supply voltage, but for a certain period of time. It is also possible to fire the thyristor at a fixed firing angle within the range, and the firing angle determination section 4a performs other arithmetic processing on the detection signal from the sensor section 3 during this time. and use the processing results for other purposes. You should be able to use it. However, in the conventional device shown in FIG. 1, every clock pulse (for example, 111
It is necessary to calculate t (for each 0'), and the firing angle determination unit 4
It was not possible to perform other data processing with a. The present invention eliminates the above-mentioned drawbacks of the conventional phase control device, makes it possible to control the firing phase of the thyristor using the detection signal from the sensor, and performs other arithmetic processing on the detection signal from the sensor. The purpose of this invention is to obtain a phase control device that can also generate and output signals for other uses depending on the results.

FIG. 3 is a block wiring diagram showing an embodiment of the present invention. In the figure, the same reference numerals as in FIG. 1 indicate the same parts, and 4
b is a central processing control unit that determines the firing angle at regular intervals according to the input signal from the sensor section 3 inputted to the input terminal IN2, and also performs various zeta processing on the detection signal from the sensor section 3. It is something to do.

The firing angle is determined once for each predetermined number (for example, m) of clock pulses input to the input terminal IN, that is, if the period of the clock pulse is T, then the period M
The firing angle is determined every time T, and control is performed using the same firing angle during the MT time.

Input terminal IN. The value m is selected in accordance with the rate of change of the input signal so that the input signal from the input signal changes only by a minute amount during the MT time. Further, the determined firing angle is stored in the central processing control unit 4b until a new value is determined, and is represented by a digital code so as to be suitable for this storage.

Its unit is the unit phase angle Δθ of AC power supply voltage (for example, Δ
θ=1°), and if the numerical value N is memorized, the firing angle is N.
The numerical value N representing the firing angle as a multiple of the above-mentioned unit phase angle Δθ is represented by, for example, a pure binary code or a BCD code, each bit of which is stored in a central processing controller. 4b output terminal 0UT,,0 port゛2,0
U.T.

,0UT. At the same time, the output terminals 0UT, 0 are output until the clock pulse at the next firing angle determination time point is input.
U.T. ,0UT. ,0UT. The output at is stored so that it does not change. Further, a pulse is outputted to the output terminal 0UT5 at the time when the firing angle is determined. 12 is a device not subject to phase control and is an output terminal 0UT of the central processing control unit 4b.

It is connected to the. 13 is a timing pulse generator that receives a clock pulse from the clock pulse generator 2 and oscillates a timing pulse, and its output is sent to a counter device 15.
is connected to the serial input terminal IN of the counter device 15.
The oscillation is stopped by the output of the output terminal 0UT.

14 is an OR gate whose one input terminal is connected to the output terminal 0UT5 of the central processing control unit 4b, and the other input terminal is connected to the output terminal 0UT of the counter device 15, and its output is connected to the preset input of the counter device 15. Connected to terminal PRESET.

The counter device 15 has parallel input terminals J, , J to which the value of each bit can be set externally. , J. , J. The parallel input terminals thereof are output terminals 0UT, 0UT2, 0UT3, 0UT of the central processing control unit 4b. The output terminal O of the counter device 15 is connected to the input terminal of the thyristor trigger section 9. FIG. 4 is a waveform diagram showing an example of waveforms in the main parts of the device shown in FIG. 3, and in FIG. , so its explanation will be omitted. 4 shows the output waveform of the timing pulse generator 13, and the waveforms shown in FIG. 4 show the output waveforms of each stage of the counter device 15. Next, the operation of the apparatus shown in FIG. 3 will be explained with reference to FIG.

The firing angle determined by the detection signal from the sensor unit 3 is converted into a digital code by the central processing control unit 4b, and is output to the output terminals 0UT, , 0UT2, 0 at the same time as the clock pulse.
U.T. ,0UT. The counter device 15 is preset by the pulse output from the output terminal 0UT5. Further, a clock pulse is input to the timing pulse generator 13. At the same time, oscillation (see FIG. 4 E) starts, and this timing pulse is inputted from the serial input terminal IN of the counter device 15, but in the embodiment shown in FIG. 3, the counter device is connected as a town counter. , the count value decreases by 1 each time one pulse is applied from its serial input terminal IN. Therefore, when a pulse is input from the ORKATE 14 to the preset input terminal PRESET, the central processing control unit 4bC7)0UT, ~0UT,
The numerical value N being output from is replaced by the counter device 15 through the parallel input terminals J, ~J, and then when N timing pulses are input from the timing pulse generator 13 through the serial input terminal, the counter device 15 The count value is O
Then, a pulse is output from the output terminal 0UT.
Now, the period of the timing pulse is the unit phase angle Δ mentioned above.
Since it is designed to be equal to θ, the period of the N timing pulses is equal to NΔθ, i.e. represents the firing angle in the central processing controller 4b, and therefore the pulses output from the output terminal ι0UT of the counter device 15. becomes the thyristor firing signal.

The oscillation of the timing pulse generator 13 is stopped by this thyristor firing signal (see waveform E in FIG. 4), and the output terminals 0UT, ~0UT of the central processing control section 4b at that point are
．． The output of is preset in the counter device 15. Fourth
In the embodiment shown in the figure, at the time of the first clock pulse, the output terminals 0, .about.0UT. The numerical value N indicated by the signal is N=9, and data processing is performed to update the numerical value N according to the input signal between the first clock pulse and the next clock pulse, and the value N changes from N=9 to N=6. An example is shown below. Therefore, the firing angle signal for nine oscillation pulses is preset in the counter device 15 by the first thyristor firing signal in the figure, and the firing angle signal for six oscillation pulses is preset by the second thyristor firing signal. The angle signal is preset (see waveform E in Figure 4). The firing phase of the bidirectional three-terminal thyristor 10 is controlled by the thyristor firing signal obtained through the above operation.

Moreover, once the central processing control unit 4b determines and outputs the firing angle, it performs various calculation processes and outputs the processed signals to the device 12 until the next determination point after a certain period of time. In the above embodiment, the clock pulse generator 2 generates the clock pulse at the zero point of the AC full-wave rectified wave, but it is not limited to this, and the clock pulse can be fired in synchronization with the phase of the AC voltage. Any phase may be used as long as it can be used as a phase reference phase.

Furthermore, the thyristor firing signal is output when the count value of the counter device 15 reaches zero, but this is different from the case where the thyristor firing signal is output when the count value is not zero but reaches another constant value. You can also design it. Further, in the embodiment shown in FIG. 3, the counter device 15 is used as a down counter, but it is also used as an up counter, and every time the counted value matches N, a thyristor firing signal is output and the counter is reset at the same time. It may be configured to do so. TE As explained above, according to the present invention, it is possible to obtain a phase control device that can control the firing phase of a thyristor and can also control devices that are not subject to phase control.

In the above explanation, an example has been described in which the phase control device of the present invention is used as an output device for a firing signal of a futhyristor, but the phase control device of the present invention can also be generally used for phase control for other purposes. It goes without saying that it can be done.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an example of a conventional phase control device, FIG. 2 is a waveform diagram showing an example of waveforms in the main parts of the device shown in FIG. 1, and FIG. FIG. 4 is a block wiring diagram showing one embodiment. FIG. 4 is a waveform diagram showing an example of waveforms in the main parts of the device shown in FIG.

In the figure, 1 is an AC power supply, 2 is a clock pulse generator,
3 is a sensor section, 4b is a central processing controller, 5 is a switching transistor, 6 is a resistor, 7 is a pulse transformer, 8
is a diode, 9 is a thyristor trigger section, 10 is a bidirectional three-terminal thyristor, 11 is a load subject to phase control, 12 is a device not subject to phase control, 13 is a timing pulse generator, 14 is an OR gate, and 15 is a counter device. be.

Claims (1)

[Scope of Claims] 1. A clock pulse generator that generates a clock pulse at a predetermined phase of the AC power supply voltage, and a timing that is synchronized with the clock pulse and has a period corresponding to a predetermined unit phase angle of the AC power supply voltage. a timing pulse generator that generates a pulse; a timing pulse generator that determines a phase angle corresponding to an input signal; and stores a numerical value representing this phase angle as a multiple of the unit phase angle; and a timing pulse generator that determines a phase angle corresponding to an input signal; a central processing controller that updates the memory of the numerical value at a cycle that is sufficiently slow relative to the rate of change of the input signal and that is multiple times the cycle of the clock pulse; A counter device that counts the timing pulses from the predetermined phase point of the AC power supply voltage and outputs a control pulse signal every time the counted value matches the numerical value stored in the central processing control unit. phase control device. 2. The phase control device according to claim 1, wherein the control pulse output from the counter device controls the firing of a thyristor device connected between the AC power source and its load. . 3. The phase control device according to claim 1, wherein the central processing control device performs other data processing at a time other than the time when data processing for updating the storage of the numerical values is performed. 4. The counter device includes a parallel input terminal for inputting the numerical value stored in the central processing control unit at the predetermined phase point of the AC power supply voltage, a series input terminal for inputting the timing pulse and counting down, and a counter device. 2. The phase control device according to claim 1, further comprising an output terminal that outputs the control pulse when the count value of becomes zero.