JP3022051B2 - AC power control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an AC power control device, and more particularly to an improvement in an AC power control device for controlling a heater or the like used as a load on the output side of a controller.

[0002]

2. Description of the Related Art As a system for controlling the temperature of a controlled object by a controller, as shown in FIG. 5, for example, a measured value from a temperature measuring sensor 3 disposed on a controlled object 1 such as a mold of an injection molding machine. A heater current flowing through a load 9 such as a heater disposed in the control target 1 by calculating a PID of an operation amount MV by a temperature control controller 5 from the PV and a preset set value SV and outputting the manipulated variable MV to an AC power control device 7. Is controlled by the AC power control device 7 in accordance with the operation amount MV. FIG.
Reference numeral 11 in the figure is a load power supply. The control method of the AC power control device 7 in such a control system generally includes phase control and time proportional on / off control.

In the former phase control method, as shown in FIG. 6, AC power control is performed by switching an AC load power supply at an arbitrary phase angle and energizing the power supply. It is possible and the control stability is high. However, since this phase control method switches an AC load power supply at an arbitrary phase angle, high-frequency noise is easily generated and is not suitable for a control system that is susceptible to noise.

The latter time-proportional on / off control method is shown in FIG.
As shown in the figure, AC power control is performed by changing the ratio of the ON time and the OFF time during a fixed period (2 seconds in FIG. 7). Since the switching is performed near the AC load power supply voltage of 0 V, noise is generated. It is also suitable for control systems that are difficult and are sensitive to noise. On the other hand, in this control method, since the time interval between the ON time and the OFF time is long, the ripple based on the control is likely to be long, and fine control cannot be expected, and there is a problem in the stability of the control. There is a time division control method as an improvement of both control methods. For example, as shown in FIG. 8, as shown in FIG.
Although the switching is performed in the vicinity of V, unlike the time proportional on / off control method, there is no cycle, and the on time and the off time are alternately and frequently repeated, so that it is difficult to generate noise and closer to the above-described phase control. There is an advantage that controllability can be expected.

FIG. 9 shows a conventional A using a time division control method.
It is a block diagram which shows C power control apparatus. That is, a charge / discharge circuit 13 including a resistor and a capacitor, and a voltage level Vm obtained by converting the manipulated variable MV from the controller 5 in FIG.
And a comparison circuit 15 that compares the charge / discharge voltage of the charge / discharge circuit 13 with the charge / discharge voltage of the charge / discharge circuit 13 and outputs a power supply on / off standby instruction signal to the load when the charge / discharge voltage exceeds the voltage level Vm.
And an AC detection unit 17 that monitors an AC load voltage waveform of the load power supply 11 and outputs a detection signal when the voltage is near 0 V. And a thyristor 21 such as a triac (trade name) for switching AC power to the load 9 by the zero-cross trigger circuit 19.

The charge / discharge circuit 13 supplies an AC signal to the load 9.
The charge and discharge are alternately switched by the zero-cross trigger circuit 19 in accordance with the power supply on / off switching timing. During the period in which the AC power is being supplied to the load 9, the load 9 is discharged and the supply of the AC power is stopped. It is configured to charge during the period. In such a conventional time-division control type AC power control device, when the charge / discharge circuit 13 repeats charge / discharge in the sections t1, t2, t3... (FIG. 10C) as shown by the solid line in FIG. At first A to load 9
Since the C power supply is stopped, the charging / discharging circuit 13 performs a charging operation, and when the charging voltage rises and exceeds the voltage level Vm of the manipulated variable MV, the comparison circuit 15 sends the on / off standby instruction signals P and Q to zero cross. Output to the trigger circuit 19.

That is, when the voltage level Vm of the manipulated variable MV exceeds the charging voltage in the section t1, the on-standby instruction signal P
Is output, the zero-cross trigger circuit 19 enters an ON standby state of AC power supply to the load 9 side. The zero-cross trigger circuit 19 to which the ON standby instruction signal P is input,
When a detection signal as shown in FIG. 10B is input from the AC detection unit 17 monitoring the AC load power supply waveform, the zero-cross trigger circuit 19 turns on the thyristor 21 in the section t2 to supply AC power to the load 9. Is done.

In the section t2, since the thyristor 21 is supplying AC power to the load 9, the charging / discharging circuit 13 performs a discharging operation and continues until the section t3. Section t
3, the discharge voltage from the charge / discharge circuit 13 decreases,
At the time when the discharge voltage falls below the voltage level Vm of the manipulated variable MV, the comparison unit 15 outputs an off standby instruction signal Q, and the zero cross trigger circuit 19 enters the off standby state of the AC power supply, while the AC detection unit 17 , The zero-cross trigger circuit 19 turns off the thyristor 21 in the section t4 to cut off the supply of AC power to the load 9.

In section t4, thyristor 21 applies A to load 9
Since no C power is supplied, the charge / discharge circuit 13 switches to the charging operation. Hereinafter, such an operation is repeated. Therefore, the AC power is supplied to the load 9 during the periods t2, t3, t5,... As shown in FIG. 10C, and if the manipulated variable MV applied to the comparison unit 15 is changed, the voltage level Vm in FIG. It is possible to change the AC power supply period that is fluctuated and supplied to the load 9.

[0010]

However, the AC power control device shown in FIG. 9 has a configuration in which the charge / discharge voltage of the charge / discharge circuit 13 is compared with the voltage level Vm of the manipulated variable MV. However, there is a dead zone of the AC power control, and the AC power supply changes stepwise with respect to the fluctuation of the manipulated variable MV. For example, in FIG. 10, even if the operation amount MV slightly changes and the voltage level Vm slightly increases, the point at which the level of the charge / discharge voltage crosses the voltage level Vm of the operation amount MV, that is, the on / off standby instruction signals P and Q are output. These points exist in the sections t1 and t3, respectively, and are not utilized in the next sections t2 and t4, so that the AC power supply waveform in FIG. 10C may not change.

As described above, even if the manipulated variable MV changes, the increase or decrease is not delayed from the section to which the point crossing the charge / discharge voltage level belongs to the subsequent section, so that the manipulated variable MV is increased by a certain degree or more. The configuration is such that the AC power supply cannot be changed unless it changes, and there is room for improvement in a control target that requires high accuracy. The present invention has been made under such a circumstance, and it is possible to make use of this in the AC power supply control even for a small change in the operation amount,
It is an object of the present invention to provide an AC power control device capable of realizing a highly accurate time division control method.

[0012]

In order to solve such a problem, the present invention provides an integrated output value obtained by subtracting and integrating a constant signal as a power supply feedback signal from a load factor corresponding to a manipulated variable, or an integrated output value thereof. An integral operation unit that integrates the load factor and subtracts the constant signal to output the integrated output value as the integrated value of the load factor, and a comparison that outputs a timing signal when the integrated output value exceeds a reference value. Part and A
An AC detection unit that detects the vicinity of the zero potential of the C load power supply and outputs a detection signal, and outputs a drive signal in which the vicinity of the zero potential is at least one unit based on a logical product of the timing signal and the detection signal. A drive unit for turning on the AC power supply to the load is provided, and a feedback signal supply unit for outputting the constant signal to the integration operation unit during the ON period of the AC power supply to the load. In the present invention, the feedback signal supply unit may be formed by the drive unit, or may be formed independently of each unit.

[0013]

According to the present invention provided with such means, the integration operation section subtracts and integrates a constant signal from the load factor corresponding to the manipulated variable, or integrates the load factor and integrates the load factor to obtain the constant signal. A subtraction integrated output value is output, a comparison unit outputs a timing signal when the integrated output value is equal to or more than a reference value, and a detection signal output from the AC detection unit when detecting near zero potential of the AC load power supply. The drive unit outputs a drive signal with at least one unit between the vicinity of the zero potential and supplies AC power to the load based on the logical product of the timing signal and the timing signal, and the feedback signal supply unit supplies the AC power to the load. The constant signal is output to the integration operation section during the supply ON period. If the feedback signal supply section is formed by the drive section, the circuit configuration can be simplified, and the feedback signal supply section can be formed independently of the respective sections according to the signal form of the load factor to be handled.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of an AC power control device according to the present invention. In FIG. 1, an integration operation unit 23 inputs an operation amount MV from a controller (not shown) (see FIG. 5) in the form of a load factor X, and supplies a power supply feedback signal (simply a feedback signal) from an output amount feedback unit 25 described later. Let G be the load factor X
, And sequentially integrates the subtraction value and outputs the result to the comparison unit 27. The subtraction value Y can be represented by Y = X−G.

Here, the load factor X can be expressed as follows, assuming that a value corresponding to 100% of the manipulated variable MV is MVmax and a value corresponding to 0% is MVmin. X = (MV−MVmin) / (MVmax−MVmi)
n) For example, in a controller of 4 to 20 mA output, the manipulated variable MV
Is 12 mA, the load factor X is (12-4) / (20-4) = 0.5. When the operation amount MV of the controller is expressed as 0 to 100%, X = MV (%) / 100 (%). Further, an integrated output value A which is obtained by integrating the subtraction value Y and output to the comparing section 27 can be expressed by the following equation.

[0016]

(Equation 1) The symbol t0 in Equation 1 indicates a power-on time, and the symbol t indicates an arbitrary time after the power-on. The integrated output value A changes as shown by, for example, a solid line in FIG. 2A, and details thereof will be described later. The comparison section 27 compares whether or not the integrated output value A from the integration operation section 23 is equal to or greater than a predetermined reference value, and outputs the timing signal B to the zero-cross trigger circuit 29 if the integration output value A is equal to or greater than the reference value. The predetermined period T is set so that high-frequency noise is not generated when the load power supply 31 is switched on and off, which will be described later.
In order to turn on and off around 0V (0 potential) of the AC load power supply waveform, the value is represented by the following equation. T = n × (1 / 2f)

Here, the symbol f is the power source frequency of the load power source 31, and the symbol n is an arbitrary integer (generally selected as 1 or 2). For example, in the case of the load power source 31 of 50 Hz, n = 1. Then, T = 10 ms, and the minimum on-time T is a half cycle of the load power supply 31. Hereinafter, a description will be given by taking n = 1 as an example. Symbols t1 to t7... Indicating sections in FIG. The reference value (1 × T) is the minimum unit of output and is an integral value during the minimum on-time T when the load factor X is “1”, and can be expressed by the following equation.

[0018]

(Equation 2) The AC detector 33 monitors the AC power supply voltage waveform of the load power supply 31 and outputs a detection signal C as shown in FIG. The zero-cross trigger circuit 29 includes a comparator 2
7 and the detection signal C from the AC detection unit 33, that is, their logical product (AN
D), an internal signal C ′ that is turned on only for a predetermined period T is internally provided. Further, when the detection signal C from the AC detection unit 33 and the internal signal C ′ are aligned, the output of the load power supply 31
A drive signal D is output so that the thyristor 35 is turned on (conducting operation) near V. Therefore, the zero-cross trigger circuit 29 is a drive unit of the thyristor 35, and the drive signal D can be represented as shown in FIG. 2D.

The load power supply 31, thyristor 35 and load 37 are connected in series to form a load circuit 39. The load power supply 31 is a general AC commercial power supply as it is or a step-up / step-down AC power supply, and the thyristor 35 is a power control semiconductor switching unit (element) such as a triac, which turns on the AC load power supply by a drive signal. Terminal type. That is, the zero-cross trigger circuit 37
Is turned on based on the drive signal D from
Supply C power (half wave power), if AC load power supply is 0V
, The power supply to the load 37 is cut off, and the next drive signal D
To supply AC power to the load 37 again. FIG. 2E illustrates such a power supply state. The load 37 is a heater, a relay, or the like disposed on a mold or the like to be controlled as described above (see FIG. 5).

Output monitors 41 are provided at both ends of the thyristor 35.
Is connected. This output monitor 41 is a thyristor 3
5 and outputs a detection signal to the output amount feedback unit 2
5, and monitors the voltage between both ends of the thyristor 35 to detect the ON operation period of the thyristor 35 from the voltage difference between both ends. FIG. 2F shows a transition of the voltage between both ends of the thyristor 35. The output amount feedback unit 25 outputs a constant value as the feedback signal G to the integration operation unit 23 during the ON operation period of the thyristor 35 based on the detection signal from the output monitor 41, and together with the output monitor 41, the feedback signal supply unit 43 are formed. The constant value of the feedback signal G during the ON operation period is “1”, corresponding to the load factor 1, and is “0” during the OFF operation period.

That is, the feedback signal supply unit 43 supplies the load 37
, A period (n) that is an integral multiple of the period T during which AC power is supplied to
× T) only the feedback signal G as shown in FIG.
, And outputs “0” to the integration operation unit 23 during a period when AC power is not supplied. Note that the load power supply 31 and the load 37 described above are A
A configuration in which the thyristor 35 is located outside the AC power control device of the present invention may be provided outside the C power control device.

Incidentally, the integral operation unit 23, the comparison unit 27, the output amount feedback unit 25 and the output monitor 41, which constitute the AC power control apparatus shown in FIG. As shown in FIG. 3, there are many examples in which the control unit 45 is mainly configured by a microcomputer. The control unit 45 has a CPU 45a having an operation and comparison / judgment function, a ROM 45b storing an operation program of the CPU 45a, an input / output interface I / O 45c, and the like. The ROM 45b has a reference for comparing with an integrated output value. The value is also stored.

The control unit 45 performs A / D conversion of the load factor X into a digital signal and outputs the converted count value to the control unit 45.
Input section 47 for outputting to the storage section, a storage section (RAM) 49 for temporarily storing the integrated output value A, and a trigger circuit 51 for generating a drive signal for turning on and off the thyristor 35 in response to a trigger active signal from the control section 45. And A described above
The C detector 33 is connected. That is, the control unit 45
Has a function of outputting a trigger active signal to the trigger circuit 51 when the detection signal C from the AC detection unit 33 and the internal signal C ′ are aligned, while functioning as the integration calculation unit 23 and the comparison unit 27 in FIG. The controller 45 and the trigger circuit 51 shown in FIG. 3 form the zero-cross trigger circuit 37 shown in FIG. The load power supply 31 and the load 37 are located outside the AC power control device according to the present invention, as in FIG.

Next, the AC of the present invention configured as described above will be described.
The operation of the power control device will be described with reference to FIG. FIG. 2A
In the sections t1 and t2, the feedback signal G is “0” because the thyristor 35 is not turned on, and the load factor X of the manipulated variable MV is subtracted from “0” by the integration operation unit 23 (substantially as it is). ) And are sequentially integrated, and FIG.
It rises as shown by the solid line of A. This integrated output value A is equal to section t.
When the value exceeds the reference value (1 × T) in the latter half of 2, the timing signal B is output from the comparator 27 to the zero-cross trigger circuit 29.

The AC detector 33 monitors the AC power supply waveform of the load power supply 31, and outputs a detection signal C to the zero cross trigger circuit 29 when detecting the vicinity of 0 V. The zero-cross trigger circuit 29 forms an internal signal C ′ that is turned on only for a predetermined period T from the logical product of the timing signal B and the detection signal C. When the detection signal C and the internal signal C ′ are aligned, the drive signal D To the thyristor 35 to turn it on. Therefore, in the section t3, the load circuit 39
Is turned on, and AC power is supplied to the load 37.

The output monitor 41 monitors the on-operation period of the thyristor 35. During the on-operation period (section t3), the output amount feedback section 25 sends a negative value of "1" to the integration operation section 23. Is output as the feedback signal G.
Since the load factor X is equal to or less than “1” (X ≦ 1), the integrated output value A from the integration operation unit 23 decreases as shown in a section t3 in FIG. 2A and falls below the reference value (1 × T). As a result, since the timing signal B is not output, the thyristor 35 does not turn on in the section t4. Therefore, the feedback signal G from the feedback signal supply unit 43 becomes “0”, and the interval t4
In the same manner as in the section t2, the integrated output value A from the integration section 27 increases and exceeds the reference value (1 × T), and the thyristor 35 is turned on by the action of the timing signal B. Thereafter, such an operation is repeated.

As described above, the AC power control device operates the operation amount M
When the integrated output value A of the load factor X based on V is equal to or greater than the reference value, AC power is supplied to the load. When the AC power is supplied, the supply is fed back and integrated while subtracting a constant value from the load factor X. To control the AC power supply to the load,
The output amount from the controller is effectively used for the AC power control in the form of the load factor X, and highly accurate time-division control can be performed. Moreover, even if the manipulated variable MV changes, the rise or fall is utilized as an integral output value A for the integral calculation and compared with the reference value, so that it is utilized in the subsequent AC power control.
There is an advantage that the AC power supply to the load 37 can be continuously controlled even if the operation amount MV does not largely change. In such an AC power control device, the load factor X corresponding to the operation amount MV can be implemented in any form of an analog signal or a digital signal.

In the above-described embodiment, the feedback signal supply unit 43 detects the supply period (ON period) of the AC power to the load 39, and feeds back the supply amount to the integration operation unit 23. However, in the present invention, as indicated by a broken line in FIG.
A configuration in which the feedback signal G is fed back to the integration operation unit 23 during the supply period of the AC power from the zero-cross trigger circuit 29 is also possible, and the zero-cross trigger circuit 29 may be formed accordingly. Thus, the zero-cross trigger circuit 2
9, the feedback signal G is fed back to the integration operation unit 23, so that it is not necessary to separately provide the feedback signal supply unit 43.
There is an advantage that the configuration is not complicated. However, the load factor X
Is operated as an analog signal, the independent feedback signal supply unit 43 accurately detects the waveforms at both ends of the thyristor 35 and feeds back the feedback signal G to the integration operation unit 23, thereby simplifying the circuit configuration. In addition, it can be operated reliably.

In the above-described embodiment, when the load factor X is operated as a digital signal, the load factor X obtained by a sampling period smaller than the predetermined period T, that is, the minimum ON period, is integrated. The invention is not limited to this. For example, every predetermined period T (minimum ON time 1 /
An operation of integrating the load factor X obtained by sampling every 2f) is also possible. That is, in the AC power control device of FIG. 1, the integration operation unit 23 synchronizes the A / D converted load factor X1 (X1n to X1n + 5..., See FIG. 4) with the detection signal b from the AC detection unit 33. On the other hand, when a feedback signal Z is input as a feedback signal from a feedback signal supply unit 43 to be described later, an integrated output value ICn subtracted by the feedback signal Z is output to the comparison unit 27. Is formed. The detailed operation of the integration operation unit 23 will be described later.

The load factor X can be converted into a digital value X1 by A / D conversion and taken in by the integration operation unit 23 in synchronization with the detection signal b from the AC detection unit 33. FIG. 4A is a voltage waveform of the AC load power supply 31,
FIG. 4B is a waveform of the detection signal b from the AC detection unit 33, and FIG.
c is a transition of the load factor X, and symbols Xn to Xn + 5 are the load factors to be A / D converted, and symbols X1n to X1n in FIG.
+5... Are A / D converted load factors. The integral value ICn in the integral operation unit 23 can be expressed by the following equation.

[0031]

(Equation 3) In the equation (3), the symbol Fm is “0” when AC power is not supplied to the load 37 (OFF), and is a constant value when the AC power is supplied (ON) (A / D conversion value when X = 1).
And the integrated value IC (n−
1) is added and the following calculation is performed. That is, the integral value ICn of the integral operation unit 23 is represented by ICn = IC (n-1) + X1n. Here, the symbol n indicates the time point n, and the item (n−
1) shows one time point before the time point n.

The integral operation section 23 outputs an integral output signal ICn obtained by subtracting the feedback signal Z from the integral value ICn. Therefore, when the integrated value ICn satisfies ICn ≧ Z, the integration operation unit 23 performs the operation shown in the following expression and replaces it, and the solid line in FIG. 5E shows the relationship. ICn = IC (n-1) + X1n-Z The comparing unit 27 compares whether or not the integrated output value ICn from the integrating operation unit 23 is equal to or more than a predetermined reference value Z. It outputs a timing signal by T to the zero cross trigger circuit 29 as a drive unit.

The load power supply 31, the AC detector 33, the thyristor 35, the load 37, and the output monitor 41 are the same as those shown in FIG. The output amount feedback unit 43 forming the feedback signal supply unit 43 together with the output monitor 41
The constant value Z described above is output to the integration operation unit 23 as a feedback signal based on the detection signal from. This feedback signal Z is a value when an output of 100% is output for the minimum ON time T, and is a count value corresponding to the above-described reference value (1 × T) in FIG.

Incidentally, the AC power control device having such a configuration is also actually constituted by a microcomputer mainly including the control unit 45 as shown in FIG. 3, and the ROM 45b has a reference value (feedback) to be compared with the output value ICn. Signal) Z, and the storage unit 49 temporarily stores the replaced integrated output value ICn. In such a second embodiment, when the load circuit 39 operates, the integral value IC
2A, the load factor X (X1) is integrated as indicated by the dotted line in FIG. 5E.
2E, and the waveform of the AC power supplied to the load 33 is also the same as that of FIG. 2E, as shown in FIG. 4G.

In the AC power control device having the second configuration, the integration calculator 23 integrates the load factor X obtained by sampling every predetermined period T and subtracts the feedback signal Z from the integrated value. When the integrated output value is equal to or more than the reference value Z, AC power is supplied to the load, and the load 3 of the AC power is supplied.
7 is fed back from the feedback signal supply unit 43 and the integration operation unit 23 controls the load 33 to supply AC power while subtracting the subtracted signal Z from the integrated value and replacing it as an integrated output value. In addition to the effects of the first embodiment described above, high-precision time-division control can be performed only by sampling and taking in the load factor X every predetermined period T.

[0036]

As described above, the present invention provides an integrated output value obtained by subtracting and integrating a constant signal from a load factor corresponding to an operation amount, or an integrated output value obtained by integrating the load factor and subtracting the integrated signal. A timing signal is output when the integrated output value is equal to or more than a reference value. A drive signal is output as one unit, and the AC power is supplied to the load based on the drive signal, and the constant signal is fed back to the integration operation during the ON period of the AC power supply to the load. Therefore, since the load factor can be sequentially made to contribute to the integral value, the load factor of the manipulated variable, which is the load factor before the AC power is supplied, is effectively used for the subsequent calculation, and the manipulated variable does not largely change. Load improves points as said not be variably controlled, it is possible to accurately control the time-sharing manner. Further, in a configuration in which the feedback signal supply unit is formed by the driving unit, the entire circuit configuration can be simplified. further,
If the feedback signal supply section is formed independently of the above sections, there is an advantage that accurate operation can be ensured without complicating the circuit configuration, for example, when the load factor is in the form of an analog signal.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of an AC power control device according to the present invention.

FIG. 2 is a waveform chart illustrating a first operation according to the AC power control device of FIG.

FIG. 3 is a block diagram showing an actual circuit configuration when commercializing the AC power control device of the present invention.

FIG. 4 is a waveform diagram illustrating a second operation according to the AC power control device shown in FIG.

FIG. 5 is a general block diagram showing a temperature control system.

6 is an AC load power supply waveform diagram for explaining a phase control method adapted to the AC power control device in FIG. 5;

FIG. 7 is an AC load power supply waveform diagram illustrating a time proportional on / off control method applied to the AC power control device in FIG. 5;

8 is an AC load power supply waveform diagram for explaining a time division control method adapted to the AC power control device in FIG.

FIG. 9 is a block diagram showing a conventional AC power control device using a time division control method.

10 is a diagram illustrating the operation of the AC power control device in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Control object 3 Sensor 5 Controller 7 AC power control device 9, 37 Load 11, 31 Load power supply 13 Charge / discharge circuit 15 Comparison circuit 17, 33 AC detection part 19 Zero cross trigger circuit 21, 35 Thyristor 23 Integral operation part 25 Output amount Feedback section 27 Comparison section 29 Zero-cross trigger circuit (drive section) 39 Load circuit 41 Output monitor 43 Feedback signal supply section 45 Control section 45a CPU 45b ROM 45c Interface I / O 47 Load ratio input section 49 Storage section (RAM) 51 Trigger circuit

Claims (3)

(57) [Claims] 1. An integrated output value obtained by subtracting and integrating a constant signal as a power supply feedback signal from a load factor corresponding to a manipulated variable, or integrating the load factor and subtracting with the constant signal to reduce the load factor. An integration operation unit that outputs an integration output value as an integration value, a comparison unit that outputs a timing signal when the integration output value becomes equal to or more than a reference value, and a detection signal that detects near zero potential of an AC load power supply and outputs a detection signal. An AC detection unit to output, and a driving unit that outputs a driving signal in which at least one unit around the zero potential is at least one unit based on a logical product of the timing signal and the detection signal to turn on AC power supply to a load, An AC power control device, comprising: a feedback signal supply unit that outputs the constant signal to the integration operation unit during an ON period of AC power supply to the load. 2. The AC power control device according to claim 1, wherein the feedback signal supply unit is the driving unit. 3. The AC power control device according to claim 1, wherein the feedback signal supply unit is formed independently of the respective units.