JPS62107315A - Phase control device - Google Patents

Abstract

PURPOSE:To obtain a constant effective value of a voltage impressed to a load by detecting a frequency variation of an AC power source, calculating a delay time so that a phase angle for applying a power source to the load is not varied, and controlling to apply the AC power source to the load. CONSTITUTION:A synchronizing signal generating means 4 generates a synchronizing signal synchronizing with a zero crossing part of an AC power source 1, and a frequency deciding means 6 detects a frequency variation of the power source. A delay time calculating means 8 calculates a delay time required for impressing a set voltage to a load, in a frequency which has been decided from a result of decision of a frequency, and a voltage which has been set by a voltage setting means 7. A control signal output means 12 outputs a control signal for applying no AC power source to a load 2 until the delay time from the synchronizing signal, and impressing it after the delay time, and a voltage impressing means 3 impresses the AC power source 1 to the load 2, based on this control signal.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a phase control device that controls the voltage applied to a load by controlling the phase of applying AC power to the load.

Conventional technology Conventionally, phase control has been used as a means to control the AC power supply voltage applied to a load, but its configuration uses the zero cross as the starting point, creates a charging waveform with a resistor and capacitor, and then adjusts the waveform to a certain level. A delay time is created by comparing the reference voltage with a comparator, etc., and the output is used as a control signal.Problems to be Solved by the InventionHowever, in the conventional configuration, once the reference voltage is determined, a delay time is generated. There is a problem in that when the time is fixed and the power supply frequency changes, the phase angle at which the power is applied to the load changes, and therefore the voltage applied to the load also changes.

Means for Solving the Problems In order to solve the above problems, the phase control device of the present invention includes:
1. a synchronizing signal generating means for generating the signal synchronized with the zero-crossing portion of the AC power source; a frequency determining means for inputting the synchronizing signal and determining the frequency of the AC power source; A voltage setting means for setting the voltage applied to the load, a frequency determined by the frequency determining means, and a voltage set by the voltage setting means.

A delay time calculation means that calculates the delay time from the zero cross point to the application of AC power to the load, and control that uses the calculated delay time and synchronization signal as input, and does not apply AC power to the load from the synchronization signal until the delay time. a control signal output means for outputting a control signal for applying an AC power to the load after the delay time; and a control signal from the control signal output means) for controlling application of the AC power to the load. It is equipped with a power supply means.

According to the above-described configuration, the present invention generates a synchronization signal synchronized with the zero cross section of the AC power supply by the synchronization signal generation means, determines the frequency of the AC power supply from the synchronization signal by the frequency determination means, and determines the determination result. From the voltage set by the voltage setting means, the delay time calculation means calculates the delay time (time from the zero cross point to the point at which power is applied to the load) necessary to apply the set voltage to the load at the determined frequency. Based on this calculation result and the synchronization signal υ, the control signal output means outputs a control signal that does not apply AC power to the load from the synchronization signal until the delay time, and applies AC power to the load after the delay time. Based on this control signal, the power supply means controls the application of AC power to the load, a delay time is automatically calculated according to the frequency of the AC power and the set voltage, and the set voltage is applied to the load.

Embodiment An embodiment of the present invention will be described based on the drawings. FIG. 1 is a system configuration diagram that is an embodiment of the present invention.

FIG. 2 is an operating waveform diagram.

First, in Fig. 1, 1 is an AC power supply, 2 is an AC power supply 1
3 is a power supply means for controlling the application of power from the AC power source 1 to the load 2; 4 is a portion where the voltage of the half-wave waveform of the AC power source 1 is 0 (hereinafter referred to as the zero cross portion);
synchronous signal generating means for generating a synchronous signal 5 synchronized with
Reference numeral 6 denotes a frequency determination means for inputting the synchronization signal 5 and determining the frequency of the AC power supply 1, 7 a voltage setting means for setting the voltage applied to the load 2, and 8 a frequency signal 9 outputted by the frequency determination means 6 and voltage setting. Setting voltage signal 10 outputted by means 7
delay time calculation means 12 which receives as input, calculates the time t (hereinafter referred to as delay time) until application of the AC power source 1 from the zero cross section to the load 2, and outputs a delay time signal 11;
inputs the delay time signal 11 and the synchronization signal 5, outputs a control signal 13 that does not apply the AC power supply 1 to the load 2 from the zero cross point to the delay time, and outputs the control signal 13 that does not apply the AC power supply 1 to the load 2 after the delay time. is a control signal output means that outputs a control signal 13 that applies a voltage to the power supply means 3.Next, in FIG. The voltage waveform of the load mill 7 + 11 is the voltage waveform. The effective value of the AC power supply voltage is vO1 The half-wave period of the AC power supply is T
Then, the effective value V of the voltage applied to the load 2 after the delay time is given by the following equation.

As can be seen from the above equation, when the frequency of the AC power source changes and the half-wave period T changes, the effective value V of the voltage applied to the load changes. Therefore, there is a problem in that even if the set value is the same in the 50 Hz region and the 60 Hz region, the voltage actually applied to the load differs.

Therefore, if the configuration shown in FIG. 1 explained above is used,
When the frequency of the AC power source changes and the half-wave period T changes, this is detected by the frequency determining means 6, and the delay time t at which the lower half waves become the same is calculated by the delay time calculating means 8, so that the half-wave period T is applied to the load 2. The effective voltage +KV does not change.

Effects of the Invention According to the invention described above, even if the frequency of the AC power source changes, it is detected by the frequency determination means, and the delay time is calculated by the delay time calculation means so that the phase angle at which the power is applied to the load does not change. However, it is configured to control the application of AC power to the load based on the calculation results.
This has the effect that even if the frequency of the AC power source changes, the effective value of the voltage applied to the load does not change.

[Brief explanation of drawings]

FIG. 1 is a system configuration diagram showing an embodiment of the phase control device of the present invention, and FIG. 2 is an operating waveform diagram. 1...AC power supply, 2...Load, 3...
... Power supply means, 4 ... Synchronization signal generation means, 6 ... Frequency judgment means, 7 ... Voltage setting means, 8 ... Delay Time calculation means, 11.
... Delay time, 12 ... Control signal output means.

Claims (1)

[Claims] an alternating current power source, a load driven by the alternating current power source, a power applying means for controlling application of the alternating current power source to the load, and a synchronizing signal generating means for generating a synchronizing signal synchronized with a zero cross section of the alternating current power source. , a frequency determining means for inputting a synchronizing signal generated by the synchronizing signal generating means and determining the frequency of the AC power source; a voltage setting means for setting a voltage to be applied to the load; and a frequency signal generated by the frequency determining means. and a delay time calculation means for calculating the time from the zero cross point of the AC power supply to the application of the AC power to the load by inputting the set voltage signal generated by the voltage setting means; and the delay time calculated by the delay time calculation means. The signal and the synchronization signal are input, and a control signal is output to the power supply means that does not apply AC power to the load from the zero cross point of the AC power supply until a delay time, and after the delay time, AC power is applied to the load. A phase control device comprising control signal output means for outputting a control signal to the power supply means.