JPS58159672A - Transistor direct firing type inverter - Google Patents

Abstract

PURPOSE:To reduce the noise contained in an output wave by performing the firing system of an output circuit by a microcomputer without resorting to wave-modulation system. CONSTITUTION:When diodes of primary sides of photocouplers H1, H2, H3 provided in an interface are respectively connected to signal output lines 101, 102, 103 from a microcomputer a to fire via sinusoidal wave sequentially from the microcomputer a, driver transistors T12-T17 are fired with sinusoidal wave through diodes D31, D32, D33 from the emitters of the photocouplers H1, H2, H3. Accordingly, the transistors T6-T11 are operated, and 3-phase sinusoidal currents of the prescribed frequency are flowed to 3-phase AC output conductors 301-303.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an inverter that manually converts a three-phase AC power source into direct current, which is then further converted into three-phase AC. It is related to.

Conventional inverters of this type are known to employ methods such as pulse wide modulation or pulse amplitude modulation.
Both methods use modulated waves in the output ignition circuit,
In other words, pulse modulation is a simple device and it is easy to generate a sine wave, but since it is a modulated wave, there is noise in the output wave, and it has the disadvantage that magnetic noise is generated in the output motor etc. There is.

The present invention uses a microcomputer to perform the ignition method of the output circuit without using modulated waves, so that the output wave has little noise and the waveform noise of the inverter does not enter the output side of general-purpose three-phase motors. The purpose is to provide a direct ignition type inverter.

Therefore, the configuration of the present invention is such that when three-phase AC power is input,
- Output circuit that converts direct current into three-phase alternating current and further converts it into three-phase alternating current.In the Q-ignition method, a sine wave three-phase signal current that is not based on modulated waves is sent to the output ignition circuit and is installed in the output circuit. It is characterized by being equipped with a microconopiator that fires each dosiher transnoster. Furthermore, to describe its specific operation, a three-phase AC 200 volt power source is input, it is turned into DC by a three-phase full-wave rectifier circuit, passed through the felter, and sent to the DC voltage adjustment circuit.
The output frequency is adjusted, and the voltage is adjusted according to the 1-cycle adjustment VC and supplied to the collector of the transistor in the output circuit. Output circuit U) [・U//A sine wave current is supplied to the base of the star from a microconopiator, and the 120 degree phase difference is created by the conopiator to fire the transistors of each phase output circuit to generate three output circuits. Obtain phase sine wave current 〒.

1. An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a circuit diagram of an embodiment of the present invention.

FIG.
)V 7i. Sweet 101,102゜10
6 is the computer a(1) signal output line, 201.
202, 205 are three-phase AC power supply human power conductors, 301, 30
2,303 indicates a three-phase paternal output conductor.

First, connect to the three-phase AC power supply human power conductors 201, 202° and 203, and connect the diode to FDI, ■) 2 + "3 + 1)
4 +D5 + D6, rectified by a full-wave rectifier circuit, converted into a P wave with a relay content of 5% by a condenser C1, suppressed the rate of increase of inopedance by a capacitor C2, and applied a voltage to the collector of a transistor T1. There is.

The base VC of the transistor T causes a base current to flow through the resistor R1 and is applied to the emitter voltage collector of the transistor T2. A transistor T is connected to the base of the transistor 'r2, and a transistor T is connected to the transistor T6, and a double volume VR is connected to the base of the transistor 'r2.
, the oscillator of the miteroccipitor a is simultaneously adjusted to change the base current of the transistor T2, thereby changing the emitter voltage of the transistor T2.

The emitter of transistor T1 is connected to resistor R3 and diode [
) 7 connected to the base of the transistor T3 11,
Pass through the Soina diode ZD and connect the transistor T.
It is said that the resistor R1+ came from the emitter of 2,
Since there is a resistor fusion and R0 all through the durant υNl), the emitter of transistor T2 Ichikawa is connected to the transistor T.
, when the emitter voltage ratio of , is 20 volts or more, the base current of transistor T3 is divided into resistor R, and enters resistor J. Because it goes down, transistor T+ and T2
U) Reduce the electric ratio drop between the collector and emitter. From one transistor T1, l
゛Hun/Staff f2? Group C is poor, but collector loss +J
, - can be changed to -r instead of f, and the stability of the transistor is 1'JL'/+).

To/Distor T2・υG resistance between collector and emitter
Insert a snubber circuit consisting of 8 and 2 nonbunsa C3 to suppress the impulse pressure of transistor T2, and
τ1 is stunned. Also, the transistor 'r2-・Wol
Mitter 1. Regarding the voltage (insert the fuse FU to protect against overcurrent, and close the output circuit)
By bypassing L3, transistor T5 + T
7 r A voltage is applied to the collector of Tg. The reactor also uses transistor T61 for the purpose of alleviating current changes.
Ding? , Tg and stabilizes the output current.

The emitter of the transistor T6 is passed through the emitter resistor l (1 degree) of the collector transistor T of the tie auto DIQ→gui, t-to D13→transnostar T, and is connected to the collector transistor T +a Wit, and is connected to the collector transistor T of the tie auto IDl0.
A three-phase father output Hikisho 301 is connected between and DI3. Similarly (if transistor T7 is connected, diode 1" DII → diode -1
connected to V between diode 1”DII and D14.
A three-phase AC output conductor 302 is connected to -C. Similarly, the emitter of transistor T8 is connected to diode D
7/emitter resistance R17k of collector transistor Tl+ of transistor TI+
connected to ground GND through diode Dfi
A three-phase AC output conductor 306 is connected between and DI6.

A snubber circuit consisting of a resistor R2+ and a capacitor C6 is inserted into the transistor T6, and a resistor R2 is inserted into the transistor T6.
A snubber circuit consisting of a resistor Ru and a capacitor C1 is inserted into the transistor T8, a snubber circuit consisting of a resistor R18 and a capacitor C5 is inserted into the transistor T9, and a snubber circuit consisting of a resistor R18 and a capacitor C5 is inserted into the transistor T8.
A snubber circuit consisting of a resistor RIll and a capacitor C8 is inserted into the transistor T11, and a snubber circuit consisting of a resistor R2o and a capacitor CI□ is inserted into the transistor T11 to protect htyj, respectively.

First, the capacitor C4 lowers the father flow resistance of the transistor T9, the capacitor Cwa lowers the AC resistance of the transistor T+o, and the capacitor C10 lowers the AC resistance of the transistor T11.

Bypass resistor R1□ is connected to the emitter of transistor T6.
A bypass resistor R13 is inserted in the emitter of the transistor T6 to cause switching to occur out of the saturation region of the transistor T6, and a bypass resistor R14 is inserted in the emitter of the transistor T8. The transistor T8 is switched out of the saturation range.

The output ignition circuit includes driver transistor T1□+
T13 + 'r,, +TI5 + Tl6 +
'r, , are provided, i.e., these transistors T1□+Tl3 +TI4+T16+T
16 + 'r, ff are transistors T6 + T? provided in the output circuit. + T8 + T9 + T10
+ T11, for each JCn driver,
In addition, the transistors T6 and T10, the transistors T7 and T11, and the transistors T6 and T11 are connected so as to fire at the same time.

FIG. 2 is a detailed explanatory diagram of the fort coupler circuit H, which is installed in the interfuniary ★ of FIG.

To explain Fig. 2, the output line 101 of the microcomputer a enters the interface Fort coupler circuit H1 to the primary side of the auto coupler PC, and a sine wave current flows through the primary side diode of the auto coupler PC. Since the secondary side transistor is switched in a sine wave, current flows from resistor RA through collector C → emitter E → resistor RE → ground GND.
A sinusoidal voltage is generated between the emitter E and the resistor RE, and the base current of the transistor TA' flows through the diode DA'i. Therefore, transistor 7 star TAf 1'F = i
-vru. The emitter B and collector C of the transistor TA are electrically connected, a voltage difference is created between the base B and the emitter E of the transistor TB, and the base current of the transistor TB flows through the resistor RB'i (a diode). No sine wave voltage is output from D31. The collector voltage of collector C or 200 volts is applied to transistor TB. Since the collector voltage of the automatic coupler PC is 65 volts, the base current of the transistor TB cannot be passed directly to the fort coupler, so the transistor TA is inserted to maintain balance.

This circuit accurately transmits the sinusoidal output current of the computer a to the driver transistor T12゜Tl3 r
This is an important point for transmitting to T14 + T15 + Tl6. If you use a normal fort coupler, the sine wave current will become a rectangular wave, and the entire modulated wave will be used.

In FIG. 2, the relationship is mainly between the driver's number output line 101 and the Fort Coupler circuit H1.

The relationship between the 1st issue output line 102 and the 7th line coupler circuit 8□ and the old issue output line 103 and the 7th line coupler circuit H
The relationship with 8 is also loJ Muku-c.

That is, as shown in FIG. 1, the fort coupler circuits HI+H2+ HB provided at the interface
Is each diode on the primary side 1? Microcomputer a's double number output line 101, 102, 106
When the positive lame wave VC is ignited in order from the computer a, the fort coupler circuit H1'r H
2r H,1 emitter to diode D31,'
Through D3□+D33', driver transistor T1□r T13 + T14 + T15 +TI6
1 Since TI7 fires sinusoidally, this causes the transistor r6 r T7 + T8 + TO+ T1
0 + T11 is activated, and a three-phase sinusoidal current of a predetermined frequency flows through the three-phase AC output conductors 301, 302, and 303.

Note that the diode DI6 + DI'l r DI8 +
Dlo + D20 + D2. is the output conductor 3 [
] i, 302 303 inductive load [' is provided to return the resulting voltage increase to the power supply.

As mentioned above, according to the invention, the output circuit is not based on the ignition force type or the modulated wave, but is based on the microcomputer, so there is no output wave, and therefore there is no noise in the output wave. Since the inverter C/) waveform noise does not enter the output side of a general-purpose three-phase induction motor, the motor can be operated with as much noise as the motor has.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an embodiment of the present invention, and FIG. 2 is a detailed explanatory diagram of one fort coupler circuit shown in FIG. a... Microcomputer, 1o1102 105
...Microcomputer (/, J) signal output line/
, 201, 202, 203. .・Three-phase AC power supply input conductor, 301, 302゜605...
・Three-phase AC output conductor, T12 r T13 +TI4
r T15 + T16 + TI□...Output ignition circuit driver transistor patent applicant Asahi Gyo Co., Ltd.

Claims (1)

[Claims] 1. Input the three-phase AC power supply and change it to -tan DC,
In the ignition method of the output circuit that further converts this into three-phase alternating current, a sine wave three-phase signal not based on modulated waves is sent to the output ignition circuit and a valley driver installed in the circuit is used. Are you familiar with the microcomputer that fires the transistors? C special, transistor direct ignition type % type %