JPH07288983A - Large capacity transformer multiplex inverter - Google Patents

Abstract

PURPOSE:To provide a large capacity transformer multiplex inverter in which the capacity can be enlarged regardless of the limit in the unit capacity of an inverter. CONSTITUTION:In a transformer multiplex inverter where inverters 11, 21 having different phases are connected with transformers T11, T21 and the outputs front the inverters are multiplexed, the inverters 11, 21 having different phases comprise a plurality of inverters 11, 12 and 21, 22, respectively. A plurality of output transformers T11, T21 and and T21, T22 are employed correspondingly in order to increase the number of turns thus enlarging the capacity of a multiplex inverter by a plurality of times regardless of the limit in the unit capacity of inverter.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to increasing the capacity of transformer multiple inverters.

[0002]

2. Description of the Related Art In a drive system for a large capacity inverter,
Transformer multiple inverter, reactor multiple inverter,
There are various methods such as direct-coupled series multiple inverters, electric motors and multiple transistor inverters.

Currently, transformer multiple inverters are widely used. An example of this transformer multiplex inverter is shown in FIGS. FIGS. 9 (A) and 9 (B) show a 12-phase multi-inverter connection and a waveform. Two three-phase inverters 1 and 2 having a phase difference of 30 ° are used, and the winding ratio is 1:
The secondary windings of the output transformer T _{1 of a} and the output transformer T ₂ having a winding ratio of 1: b and 1: b are connected as shown in the drawing to multiplex the outputs of the inverters 1 and 2. In this case, the fifth and seventh high frequencies are eliminated and the pulsating torque is only an integral multiple of 12f (f: operating frequency).

FIGS. 10 (A) and 10 (B) show the wiring and waveform of an 18-phase multiple inverter, which uses three three-phase inverters 1 to 3 whose phases are different by 20 °. The secondary windings of the output transformers T _{1 to} T ₃ are connected as shown to multiplex the outputs of the inverters 1 to 3. In this case, the 5th, 7th, 11th, 13th high frequencies are erased,
The pulsating torque is only an integral multiple of 18f.

FIGS. 11 (A) and 11 (B) show the wiring and waveforms of a 24-phase multiple inverter, which uses four three-phase inverters 1 to 4 whose phases are different by 15 °. The secondary windings of the output transformers T _{1 to} T ₄ are connected as shown to multiplex the outputs of the inverters 3 _{1 to} 3 ₄ . In this case, the 5th, 7th, 11th, 13th, 17th, 19th
The high frequency is erased, and the pulsating torque is only an integral multiple of 24f.

As described above, the capacity of the transformer multiplex inverter can be increased by the number of inverters.

[0007]

In order to further increase the capacity of such a transformer multiplex inverter, it is necessary to increase the capacity of the single inverter unit. There is a limit to the capacity of a single inverter unit due to restrictions on the number of main circuit elements (for example, GTOs, power transistors, IGBTs) and the number of series / parallel circuits.

The present invention has been made in view of such conventional problems, and an object thereof is to provide a large capacity transformer multiple inverter capable of expanding the capacity regardless of the limit of the capacity of a single unit of the inverter. To provide.

[0009]

In order to achieve the above object, a large capacity transformer multiple inverter according to the present invention comprises:
The transformer multiplex inverter is characterized by having a plurality of inverters each having a different phase and correspondingly increasing the number of output transformer windings to increase the capacity.

[0010]

Since the plurality of inverters having different phases are provided and the number of output transformer windings is increased correspondingly, the output of the transformer multiplex inverter is increased a plurality of times. Therefore, the capacity can be increased regardless of the limit of the capacity of the single inverter unit.

[0011]

Embodiments of the present invention will be described with reference to the drawings.

Embodiment 1 (FIGS. 1 to 3) FIG. 1 is a connection diagram showing a configuration of a 12-phase transformer multiplex inverter, where E is a DC power supply section (converter section) of the inverter,
1 ₁ and 1 ₂ are reference (0 °) inverters, 2 ₁ and 2 ₂ are inverters delayed by 30 ° from the reference inverters 1 ₁ and 1 ₂ , T
₁₁ and T ₁₂ are output transformers connected to the output sides of the inverters 1 ₁ and 1 ₂ with a winding ratio of 1: a, and T ₂₁ and T ₂₂ are winding ratios connected to the output sides of the inverters 2 ₁ and 2 _2. 1: b,
In the output transformer of 1: b, the secondary windings a and b of the transformers T _{11 to} T ₂₂ are connected so that the output voltages are vector-combined as shown in FIG. 2, and are multiplexed to the terminals U, V and W. It is configured to output the generated three-phase alternating current.

As a result, the capacity of the multiple inverter can be doubled as compared with the capacity of the conventional system shown in FIG.

FIG. 3 shows a waveform example of the output voltage of the 12-phase transformer multiplex inverter. Compared with the conventional method, this method only increases the number of inverters and transformer windings (number), so the voltage waveform is the same as the conventional method.

Embodiment 2 (FIGS. 4 and 5) FIG. 4 is a connection diagram showing the structure of an 18-phase transformer multiplex inverter, where E is the DC power supply section (converter section) of the inverter,
1 ₁ and 1 ₂ are reference (0 °) inverters, 2 ₁ and 2 ₂ are inverters delayed by 20 ° from the reference inverters 1 ₁ and 2 ₂ , 3
₁ and 3 ₂ are inverters delayed by 40 ° from the reference inverters 1 ₁ and 2 ₂ , T ₁₁ and T ₁₂ are output transformers connected to the output side of the inverters 1 ₁ and 1 ₂ with a winding ratio of 1: a, T ₂₁ And T ₂₂ are output transformers connected to the output side of the inverters 2 ₁ and 2 ₂ with a winding ratio of 1: b, 1: c, and T ₃₁ and T ₃₂ are windings connected to the output side of the inverters 3 ₁ and 3 ₂ . Line ratio 1: b,
In the output transformer of 1: c, the secondary windings a, b and c of the respective phases of the transformers T _{11 to} T ₃₂ are connected so that the output voltages are vector-combined as shown in FIG. It is configured to output a three-phase alternating current multiplexed on V and W.

As a result, the capacity of the multiple inverter can be doubled as compared with the capacity of the conventional system shown in FIG.

Embodiment 3 (FIGS. 6 and 7) FIG. 6 is a connection diagram showing a configuration of a 24-phase transformer multiple inverter, where E is a DC power supply section (inverter section) of the inverter,
1 ₁ and 1 ₂ are reference (0 °) inverters, 2 ₁ and 2 ₂ are inverters delayed by 15 ° from the reference inverters 1 ₁ and 1 ₂ , 3
₁ and 3 ₂ are reference inverter ₁ 1, 1 ₂ from 30 ° delayed inverter 4 ₁ and 4 ₂ are reference inverter ₁ 1, 1 ₂ from 4
Inverters delayed by 5 °, T ₁₁ and T ₁₂ are inverters 1 ₁
And 1 _second output connected windings ratio side 1: a of the output transformer, T ₂₁ and T ₂₂ is the inverter 2 ₁ and 2 ₂ output connections windings ratio side 1: b, 1: the d Output transformer, T
₃₁ and T ₃₂ are output transformers connected to the output sides of the inverters 3 ₁ and 3 ₂ with a winding ratio of 1: c, 1: c, T ₄₁ and T _42.
Is an output transformer connected to the output side of the inverters 4 ₁ and 4 ₂ with a winding ratio of 1: d, 1: b.

Secondary winding a of each phase of the transformers T _{11 to} T ₄₂
To d are connected so that the winding voltages are vector-combined as shown in FIG. 7, and terminals U, V. It is configured to output a three-phase alternating current multiplexed on W.

As a result, the capacity of the multiple inverter can be doubled as compared with that of the conventional system shown in FIG.

In the first to third embodiments, the system in which the capacity of the transformer multiplex inverter is doubled has been described. However, by using a plurality of inverters each having the same phase and increasing the number (number) of windings of the output transformer in the same manner. It is possible to further expand the capacity.

Further, the DC power source E of the inverter (PWM system) may be constituted by a converter R as shown in FIG. 8, and the converter may be a PAM control system and a PAM + PWM combined type. When the PAM control method is also used, the inverter can be a 180-degree square wave inverter.

[0022]

According to the present invention, in a transformer multiplex inverter, a plurality of inverters having the same phase are provided respectively, and the number of windings of the output transformer is increased in accordance with the number of inverters. Therefore, the capacity of the transformer multiplexor is multiplied. The capacity can be increased.

[Brief description of drawings]

FIG. 1 is a configuration explanatory diagram of a 12-phase transformer multiple inverter according to a first embodiment.

FIG. 2 is a vector diagram of an output voltage according to the first embodiment.

3 (A), (B), and (C) are waveform diagrams showing the 0 ° inverter output voltage, −30 ° inverter output voltage, and transformer multiple output voltage according to the first embodiment.

FIG. 4 is an explanatory diagram of a configuration of an 18-phase transformer multiplex inverter according to the second embodiment.

FIG. 5 is a vector diagram of an output voltage according to the second embodiment.

FIG. 6 is an explanatory diagram of a configuration of a transformer 24-phase multiple inverter according to a third embodiment.

FIG. 7 is a vector diagram of an output voltage according to the third embodiment.

FIG. 8 is a block circuit diagram showing an example of an inverter control system.

FIG. 9 is a structural explanatory view of a 12-phase transformer multiple inverter according to a conventional example.

FIG. 10 is a structural explanatory view of an 18-phase transformer multiple inverter according to a conventional example.

FIG. 11 is a structural explanatory view of a 24-phase transformer multiplex inverter according to a conventional example.

[Explanation of symbols]

1 ₁ to 4 ₂ ... Inverter T _{11 to} T ₄₂ ... Transformer a to d ... Secondary winding of transformer E ... DC power supply unit (converter unit) R ... Converter C ... DC capacitor

Claims (4)

[Claims] 1. A transformer multiplex inverter in which a transformer is connected to each inverter having a different phase, and the output of each inverter is multiplexed and output by a transformer, and a plurality of each inverter having a different phase is provided. A large-capacity transformer multiple inverter characterized by increasing the capacity by correspondingly increasing the number of output transformer windings. 2. The large capacity transformer multiple inverter according to claim 1, wherein the transformer multiple inverters are connected in 12-phase, 18-phase or 24-phase. 3. The large capacity transformer multiple inverter according to claim 1 or 2, wherein the converter section of the inverter is under PAM control and the inverter is under PWM control. 4. The converter according to claim 1, wherein the converter section of the inverter is of a PAM control system, and the inverter is 18
Large-capacity transformer multiple inverter characterized by being a square wave inverter with 0 ° flow.