JPS59230497A - Controller for motor - Google Patents

Abstract

PURPOSE:To obtain stable ON/OFF time by crossing the output voltage of a CR charging circuit and the rising or falling edge of a rectangular voltage. CONSTITUTION:When a power source is energized, the capacitor 10 of a CR charging circuit 6 is charged at every positive half wave. When the voltage of the capacitor 10 becomes the same potential as the falling edge of the rectangular wave of a power source phase circuit 2, the output of a comparator 11 becomes L, and a thyristor 12 is turned ON. Simultaneously, the capacitor 10 is discharged. At this time, the potential of the capacitor 10 is crossed at the rising edge of the rectangular wave of the power source phase circuit 2, and the output of the comparator 11 becomes H at this time. Since the power source phase at the crossing time is positive half wave, the thyristor 12 continues ON during the remaining positive half wave. In this manner, the power source phase of starting ON and OFF of the motor is accurately determined, thereby obtaining the stable ON/OFF time.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a control device/apparatus that is incorporated into equipment such as a hand mixer.

Conventional configurations and their problems Traditionally, AC motor control devices have a duty system, but with a simple duty system, there is a problem that when it turns on, it turns on from a certain phase, so the zero cross switch circuit is used as a duty circuit. It was added to. This resulted in an increase in cost.

Furthermore, in order to increase the accuracy of the on/off time error to within the error of one cycle of the power supply, it was necessary to either complicate the circuit or increase the accuracy of the circuit components.

Purpose of the Invention In view of the above-mentioned drawbacks of the conventional art, the present invention has a simple circuit configuration and uses all circuit components of general accuracy to perform on-on duty control of the motor at zero cross, and to eliminate errors in the on-off period from the power source. The purpose is to provide a device that has accuracy that suppresses errors within a cycle, and to finely control the torque and rotational speed of a motor.

Structure of the Invention In order to achieve the above object, the motor control device of the present invention comprises:
A power supply phase circuit that generates a rectangular wave in synchronization with the power supply phase;
It includes an on/off time setting circuit that sets the on/off time of the motor, a drive circuit for the motor and a thyristor that drives the motor, and an OR charging circuit.A power line is connected to the input of the power phase circuit, and its output is as follows. The output of the CR time constant circuit is connected to the other input of the on/off time setting circuit, and the input of this OR charging circuit is connected to the other end of the motor whose one end is connected to the power supply line, and the thyristor. The output of the on/off time setting circuit is connected to the input of the thyristor drive circuit.

With this configuration, on/off starts at the intersection of the edge of the rectangular wave output from the power supply phase circuit and the output from the OR charging circuit. In other words, the rotational speed and torque of the motor can be finely controlled by controlling the motor on and off in synchronization with the power supply phase, rather than simply controlling the motor by turning it on and off.

DESCRIPTION OF EMBODIMENTS Hereinafter, a practical example of the present invention will be described with reference to the drawings. 1 and 2 are circuit diagrams of the motor control device of this embodiment, where 1 is an AC power supply, 2 is a power supply phase circuit that generates a rectangular wave in synchronization with the phase of the power supply, and 3 is a motor on/off time. The on/off time setting circuit to be set, 4 is the motor,
6 is a motor 4 and a thyristor 12 that drives this motor 4.
A fully driven thyristor drive circuit, 6 is an OR charging circuit,
7 indicates a constant voltage circuit, one end of the resistor 8 which is the input of the power supply phase circuit 2 is connected to the power supply line, and the e terminal of the comparator 9 which is the output thereof is connected to the ■ terminal of the comparator 11 of the on/off time setting circuit 3. It's wandering. The capacitor 1o, which is the output of the i L CR charging circuit 6, is connected to the comparator 11.
is connected to the e terminal of and! The anode of the diode 14, which is the input of the OR charging circuit 6, is connected to the other end of the motor 4, one end of which is connected to the power supply line, and the anode of the thyristor 12, which is the output of the thyristor drive circuit 6. The output of the comparator 11, which is the output of the on/off time setting circuit 3, is connected to one end of a resistor 13, which is the input of the Cyrisk drive circuit 6.

Next, the operation of the motor control device configured as described above will be explained.

A constant voltage circuit 7 charges a capacitor 23 through a resistor 8 and diodes 21 and 22, and outputs a constant voltage through a resistor 24 and a constant voltage diode 25.

In addition, in the power supply phase circuit 2, a positive half wave is applied from the power supply 1 to the resistors 26 and 27 through the resistor 8 and the diode 21, and the voltage of the resistor 27 is applied to the e terminal of the comparator 9. Resistors 28, 29.3 are connected to the ■ terminals of
The other end of the resistor 28 is connected to the high voltage side of the constant voltage, the other end of the resistor 24 is connected to the low voltage side of the constant voltage, and the other end of the resistor 30 is connected to the output of the comparator 9. When the power supply voltage is zero potential, the output of comparator 9 is High.
h, a resistor 28 is connected to the ■ terminal of the comparator 9,
When the divided voltage vHigh of the resistor 29 is applied and the power supply voltage increases, and the voltage of the resistor 27 becomes equal to "f(high", the output of the comparator 9 becomes Low.9, and the resistor 30 is connected in parallel with the resistor 29. , the ■ terminal voltage of the comparator 9 becomes vLOw, and then when the power supply voltage decreases to vLOw, the output of the comparator 9 becomes Low, and thereafter a rectangular wave is generated in synchronization with the power supply phase (see 3rd g1F).

The output of the comparator 9 is connected to the base of a transistor 31, and when the output is High, the transistor 31 is turned on, and when the output is Low, it is turned off. Accordingly, one end of the resistor 32 connected to the collector of the transistor 31 is connected in parallel with the resistor 34, so when the output of the comparator 9 is High and the transistor 31 is off, the constant voltage is applied to the resistor 34. When the output of comparator 9 is High, the voltage is divided by 34 and the specific voltage is
1 is on, the constant voltage is applied to resistors 33 and 34.
A voltage divided by 32 parallel combined resistors is applied to the ■ terminal of the comparator 11 (see FIG. 3). Therefore, when the output of the comparator 11 becomes Low, the resistor 19 is connected in parallel to the resistor 34, so that the output of the comparator 11 becomes low.
The potential of the terminal is High when the output of the comparator 11 is
The potential drops further than when . When the entire circuit is in operation, the voltage waveform at the terminal (2) of the comparator 11 becomes as shown in FIG. 3A.

Now, when the power is turned on, the capacitor 10 of the CR charging circuit 6 is charged from the power supply via the motor 4, the diode 14, and the resistor 36. At that time, the output of the comparator 11 is High, so the transistor 15 is turned on,
The gate of thyristor 12 becomes Low, and thyristor 1
2 is not turned on, and the capacitor 10 continues to charge. The waveform B in FIG. 3 is a capacitor 100 waveform, which charges only the positive half wave, and holds the charging voltage because there is no discharge path during the negative half wave. Thereafter, the positive half-wave is repeated several times, and the voltage of the capacitor 1o (voltage of B) increases with each positive half-wave, and the potential of the ■ terminal input of the comparator 11,
That is, when the potential is the same as the falling edge of the rectangular wave synchronized with the power supply phase of the output of the power supply phase circuit, the waveform of the third output of the comparator 11, which is the output of the on/off time setting circuit, becomes Low, and the transistor 16 is turned off. , a voltage is applied to the gate of the thyristor 12 via the resistor 16, and the thyristor 12 is turned on. At the same time that the thyristor 12 is turned on, charging of the capacitor 1o is stopped, and conversely, discharging is started via the resistor 17 and the diode 18. As the potential of the capacitor 10 decreases, the output of the power supply phase circuit (waveform in FIG. 3A) and the output of the comparator 11 become Low, and the resistor 19 is grounded via the diode 20, resulting in a low potential rectangular wave. , the waveform of FIG. 3C crosses at the rising edge (the positive half-wave of the power supply phase), at which time the comparator 11 is inverted and its output becomes High,
The gate of thyristor 12 becomes Low.

However, since the power supply phase at the time of crossing is a positive half wave, the thyristor 12 continues to be turned on during the remaining positive half wave. At that time, capacitor 10 is not charged because thyristor 12 is on. Charging begins for the first time in the next positive half wave (the thyristor is turned off during this charging period). After repeating this on and off, the thyristor 12
is turned on and the motor 4 is controlled on and off in synchronization with it.

Effects of the Invention As described above, the motor control device of the present invention generates a rectangular wave using a power supply phase circuit, and starts turning on the motor by crossing the output voltage of the CR charging circuit with the rising or falling edge of the rectangular wave. Since the power supply phase at the start of off is determined accurately, stable on-off times can be obtained. Furthermore, if the intersecting phases are set near zero volts, a thyristor zero volt switch circuit is constructed, and the noise prevention effect is excellent. Furthermore, since the CR charging circuit crosses at the edge, even if the voltage at the edge is wide enough, even if the parts of the CR charging circuit are uneven, it can be absorbed sufficiently, and it is possible to suppress the variation in on and off times. can.

In this way, by accurately determining the number of positive half-wave pulses when the motor is on and off, the rotational speed and torque of the motor can be finely controlled.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a motor control device showing an embodiment of the present invention, Fig. 2 is a circuit diagram of the same device, and Fig. 3 is a waveform diagram of each part corresponding to A-F of the circuit in Fig. 2. be. 1...Power source, 2...Power phase circuit, 3
......On-off time setting circuit, 4...Motor, 6...Sirisk drive circuit, 6...
...CR charging circuit, 12... Thyristor, 9
．． 11...contractor. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure Otsu Figure 2 Figure 3

Claims (1)

[Claims] A power supply phase circuit that generates a rectangular wave in synchronization with the power supply phase;
It is equipped with an on-off time setting circuit that sets the on-on time of the motor, a drive circuit for the motor and a thyristor that fully drives the motor, and an OR charging circuit.A power line is connected to the input of the power phase circuit, and its output is connected to one side. The output of the OR charging circuit is connected to the other input of the on/off time setting circuit, and the input of this OR charging circuit is connected to the other end of the motor whose one end is connected to the power supply line, and the thyristor drive circuit. The output of this on/off time setting circuit is connected to the input of the thyristor drive circuit, which is a motor control device that performs on/on control of the n1 motor.