JP2996064B2 - Bridge type inverter device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a single-phase or multi-phase inverter device in which switching elements are bridge-connected.

[0002]

2. Description of the Related Art When a switching element of a bridge type inverter for converting DC to AC is turned on / off, switching loss occurs in the switching element.

It is an object of the present invention to provide a bridge-type inverter device that can reduce switching loss with a relatively simple circuit configuration.

[0004]

SUMMARY OF THE INVENTION The present invention for achieving the above object will be described with reference to the reference numerals in the drawings showing the embodiments. First DC power supply 1 having a positive terminal and a negative terminal is described below.
a, a positive terminal and a negative terminal, the positive terminal being connected to the negative terminal of the first DC power supply 1a, the second DC power supply 1b, and the first DC power supply 1a A first switching element SW1 connected between the positive terminal of the load 2 and one end of the load 2, and a second switching element SW1 connected between the negative terminal of the second DC power supply 1b and one end of the load 2. Switching element S
W2 and the first and second switching elements SW1, S
A single-phase or multi-phase bridge-type or half-bridge-type inverter device having first and second main diodes D1 and D2 respectively connected in reverse parallel to W2 and supplying AC power to a load 2. , First and second auxiliary diodes DL1, DL2 connected in reverse direction to the first and second switching elements SW1, SW2, respectively.
And the first and second switching elements SW1, SW
2 and the first and second auxiliary diodes DL1, DL2
And the first and second reactors L1 and L2, which are connected in parallel with the first and second main diodes D1 and D2 and are electromagnetically coupled to each other, respectively. , The first DC power supply 1a and the second
A capacitor C1 connected between a midpoint of connection with the DC power supply 1b and a midpoint of connection between the first main diode D1 and the second main diode D2; The first for turning on the two switching elements SW1 and SW2.
And a second control pulse, wherein the first control pulse
And a switch control circuit which is set so that the second control pulse is generated alternately with an overlapping period in part. It relates to a fbridge type inverter device. Further, an inverter device can be configured as described in claims 2 to 8.

[0005]

According to the invention of each claim, zero volt switching at the time of turning off or turning on the main switching elements SW1 and SW2 by resonance operation of the capacitor C1 or the auxiliary capacitors Cs1 and Cs2 and the reactors L1 or L1 and L2. ZVS) or zero current switching (ZCS) is possible and power loss is reduced. Further, ZVS or ZCS can be realized with a simple circuit configuration without providing a special switch.

[0006]

First Embodiment Next, a bridge type inverter device according to a first embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 1, this inverter device is configured to convert a DC voltage of a DC power supply 1 into an AC by a bridge type inverter circuit and supply the AC to a load 2. The DC power supply 1 includes a rectifier circuit or a battery, and supplies a power supply voltage V. The power supply 1 includes first and second power supply capacitors 1.
a and 1b are connected. Each power supply capacitor 1a, 1
b has a positive terminal and a negative terminal, the positive terminal of the first power supply capacitor 1a is connected to the positive terminal of the power supply 1, and the negative terminal of the second power supply capacitor 1b is the power supply 1 Is connected to the negative terminal. The negative terminal of the first power supply capacitor 1a and the positive terminal of the second power supply capacitor 1b are connected to each other so that a connection midpoint P1 is obtained. Since the power supply capacitors C1 and C2 have the same capacitance,
It functions as a power supply of a voltage half of the voltage V of the power supply 1.
The load 2 includes, for example, an output transformer 3 and a load circuit 4 connected to the secondary side.

The inverter circuit has a first, second, third, and fourth switching element S similar to a typical inverter.
W1, SW2, SW3, and SW4, and first, second, third, and fourth auxiliary diodes DL in addition to first, second, third, and fourth main diodes D1, D2, D3, and D4.
1, DL2, DL3, DL4, first and second capacitors C1, C2, and first, second, third and fourth reactors L1, L2, L3, L4. In the following, each circuit element may be indicated only by a symbol.

The first, second, third and fourth switching elements SW1, SW2, SW3 and SW4 are constituted by bipolar transistors. However, the switching elements SW1 to SW4 can be field effect transistors (FETs). The first switching element SW1 is
The first switching element SW2 is connected between the positive terminal of the power supply capacitor 1a and one end of the load 2 via a first reactor L1, and the second switching element SW2 is connected between the one end of the load 2 and the second power supply capacitor 1b. The second reactor L2 between the side terminal
And the third switching element SW3 is connected between the positive terminal of the first power supply capacitor 1a and the other end of the load 2 via a third reactor L3. SW4 is connected via a reactor L4 between the other end of the load 2 and the negative terminal of the second power supply capacitor 1b.

The first, second, third and fourth main diodes D1, D2, D3 and D4 are connected to the first, second, third and fourth switching elements SW1, SW2, SW3 and SW4, respectively. They are connected in parallel in the reverse direction via fourth reactors L1 to L4. 1st to 4th auxiliary diode D
L1 to DL4 are the first without the reactors L1 to L4.
To the fourth switching elements SW1 to SW4. The first to fourth switching elements SW
When 1 to SW4 are insulated gate (MOS) field effect transistors having a structure in which the source is connected to the substrate, the diodes incorporated therein can be used as auxiliary diodes DL1 to DL4.

The first capacitor C1 is connected between a connection point P1 between the first and second power supply capacitors 1a and 1b and a connection point P2 between the first and second main diodes D1 and D2. Have been. The second capacitor C2 is connected between the connection point P1 between the first and second power supply capacitors 1a and 1b and the connection point P3 between the third and fourth main diodes D3 and D4. .

The control terminals (bases) of the switching elements SW1 to SW4 are connected to a control circuit 5. The control circuit 5 includes first, second, third, and fourth control pulse generation circuits 6, 7, 8, and 9, an oscillator 14, and a phase control circuit 15, as shown in principle in FIG. . The first to fourth control pulse generation circuits 6 to 9 include an oscillator 14 and a phase control circuit 1
5 to generate the first to fourth control pulses shown in FIGS. 3A, 3B, 3C, and 3D and supply them to the first to fourth switching elements SW1 to SW4. .

The first and second control pulses shown in FIGS. 3A and 3B have sections T3 to t4 and t7 to t8 overlapping each other, and are generated alternately with a phase difference of about 180 degrees. , FIG.
The third and fourth control pulses of (C) and (D) are generated in the same manner.

The basic operation of the inverter circuit shown in FIG. 1 is the same as that of a known inverter. That is, while the first and fourth switching elements SW1 and SW4 are simultaneously turned on, the current in the first direction is generated by a circuit including the power supply 1, the first switching element SW1, the load 2, and the fourth main switching element SW4. Flows into the load 2, and during the period when the second and third main switching elements SW2 and SW3 are simultaneously turned on, a load 2 and a second switching element SW2 are used in a circuit composed of the power supply 1, the third switching element SW3, the load 2 and the second switching element SW2. Current flows in the second direction.

FIG. 4 shows a case where the load 4 is unloaded and the load circuit 2 is a delay load of only a transformer, and
1 shows the state of each section in FIG. When the second switching element SW2 is turned on at time t3 in a state where the first capacitor C1 is charged to approximately half of the power supply voltage V, the first capacitor C1, the second reactor L2, and the second resonant circuit including a second switching element SW2 and the second power supply capacitor 1b is formed, sinusoidal current I _L2 of the current I _C1 and the second reactor L2 of the first capacitor C1 as shown in FIG. 4 Flows to As a result, the voltage VC1 of the first capacitor C1 gradually decreases and becomes -V / 2 at time t4 '. The voltage V2 between both terminals of the second main diode D2 is almost the same as the voltage of the reactor L2, and the voltage of the reactor L2 changes from V to 0 at 1/2 {V (1 + cos .omega.t)}. The voltage V2 with the second main diode D2 also gradually decreases from V to 0 as shown in FIG. On the other hand, the voltage V1 of the first main diode D1 is the voltage V / 2 of the first power supply capacitor 1a and the voltage V1 of the first capacitor C1.
C1 and the voltage VC1 of the first capacitor C1.
As shown in FIG. 4, the voltage gradually rises according to a sinusoidal change from + V / 2 to -V / 2. Note that t3 to t4 '
In the interval, a current _IL1 passing through the first reactor L1 flows through a circuit including the first capacitor C1, the first reactor L1, the first auxiliary diode DL1, and the first power supply capacitor 1a. SW1 is between T1 and t.
Turn off while 4 'resonant current is flowing. This allows SW1 to be substantially ZVS and ZCS,
ZCS of SW2 becomes possible.

In the section near t7 to t8 in FIG.
The same operation as in the section near .tau.4 occurs. In FIG. 4, the DC exciting currents of L1 and L2 are ignored.

[0016]

Second Embodiment Next, a bridge-type inverter device according to a second embodiment of the present invention will be described with reference to FIGS. However, in FIG. 5, portions common to FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. The inverter circuit shown in FIG. 5 has first to fourth switching elements SW1 in FIG.
The connection of the first to fourth auxiliary diodes DL1 to DL4 connected in parallel in the reverse direction to the switches SW1 to SW4 is changed.
That is, in FIG. 5, the first auxiliary diode DL1 is connected to the negative terminal of the second power supply capacitor 1b and the first reactor L1.
And the second auxiliary diode DL2
Is connected between the lower end of the second reactor L2 and the positive terminal of the first power supply capacitor 1a, and the third auxiliary diode DL3 is connected to the negative terminal of the second power supply capacitor 1b and the third reactor. A fourth auxiliary diode DL4 is connected between the lower end of the fourth reactor L4 and the positive terminal of the first power supply capacitor 1a. The first and second reactors L1, L2
And the third and fourth reactors L3 and L4 are not electromagnetically coupled to each other.

The control pulses for the switching elements SW1 to SW4 in FIG. 5 are as shown in FIGS.
SW1 and SW2 and SW3 and SW4 are alternately turned on and off with a phase difference of 180 degrees. FIG. 7 shows the load 4
In the section corresponding to near t3 in FIG.
And ON / OFF states of the second switching elements SW1 and SW2, and voltages V _sw1 , V _sw2 and V2 of I _L1 , I _L2 , SW1 and SW2. In FIG. 5, C2 is charged to V / 2 during the ON period of SW1. SW2 is turned on at the same time as SW1 is turned off. When SW1 turns off, L1
Current is commutated from SW1 to DL1 and L1 and C1
Circuit of power supply 1b and DL1 and C1, L2 and SW
Sinusoidal currents I _L1 and I _L2 flow through the resonance circuit between the power supply 2 and the power supply 1b. Voltage V2 of the voltage waveform i.e. D2 of L2 is changed to a cosine wave, the I _L2 when this becomes zero peak - reached click value, then continues to flow a circulating current. SW2 becomes ZCS because I _L2 rises from 0 when it is on. Further, SW1 becomes ZVS due to a delay in rising of _Vsw1 due to a parasitic capacitor (storing capacitance) of SW1 when turned off.

[0018]

Third Embodiment Next, an inverter device according to a third embodiment will be described with reference to FIGS. However, in FIG. 8, portions common to FIGS. 1 and 5 are denoted by the same reference numerals, and description thereof will be omitted. The circuit of FIG. 8 is the first to fourth circuit of the circuit of FIG.
The first to fourth auxiliary capacitors Cs1 to Cs4 are connected in parallel to the switching elements SW3 to SW4.

When the first to fourth auxiliary capacitors Cs1 to Cs4 are connected as compared with the parasitic capacitor of FIG. 5, the ZVS of SW1 becomes more reliable as shown in FIG.

Although a loss due to Cs1 to Cs4 occurs,
This can be reduced by setting the capacitance of Cs1 to Cs4 smaller than that of C1 to C4.

[0021]

Fourth Embodiment Next, a half-bridge type inverter device shown in FIG. 10 will be described. However, in FIG.
The same reference numerals are given to the same parts as those described above, and the description thereof will be omitted. The inverter circuit of FIG. 10 has a configuration in which the right half of the inverter circuit of FIG. 1 is replaced with first and second power supply capacitors Ca and Cb having the same capacity. That is,
A series circuit of first and second power supply capacitors Ca and Cb is connected between one end and the other end of the power supply 1, and the other end (right end) of the load 2 is connected to a connection midpoint between these. I have.

In this half-bridge type inverter circuit, first, the first and second power supply capacitors Ca,
Cb is charged to half the value of the voltage V of the power supply 1. In this state, when the first switching element SW1 is turned on and the second switching element SW2 is turned off, the first switching element SW1, the load 2, and the second power supply capacitor Cb in the circuit of the power supply 1, the first switching element SW1, And the second power supply capacitor Cb is charged. Further, a discharge current in the first direction flows through the circuit including the first power supply capacitor Ca, the first switching element SW1, and the load 2. At this time, a voltage of V / 2 is applied to the load 2. Next, during the ON period of the second switching element SW2, the power supply 1, the first power supply capacitor Ca and the load 2
And a second switching element SW2, a current in the second direction flows, and a circuit including the second power supply capacitor Cb, the load 2, and the second switching element SW2 causes the current to flow in the second direction. A discharge current flows. Also in the half-bridge type inverter of FIG.
Since the diodes DL1 and DL2 and the reactors L1 and L2 are provided as in FIG. 1, the same effects as in FIG. 1 can be obtained.

In FIG. 10, the left side of the load 2 can be the same as the left half of FIG. 5 or FIG. 8 or another embodiment described later.

[0024]

Fifth Embodiment Next, a three-phase bridge type inverter device shown in FIG. 11 will be described. However, portions common to FIG. 1 are denoted by the same reference numerals, and description thereof is omitted. In this embodiment, first, second and third phase switch circuits Su, Sv and Sw are connected between the power supplies 1, 1a and 1b and the three-phase load 2. Each of the switch circuits Su, Sv, Sw is the same as the switch circuit in the left half of FIG. In each switch circuit Su, Sv, Sw, the output line 2 of each phase starts from the connection point of the first and second switching elements SW1, SW2.
1, 22, 23 are derived and connected to the three-phase load 2. As is well known, the first to third phase switch circuits Su, Sv, Sw are driven at an angle interval of 120 degrees. Also in this three-phase inverter, the switch circuit of each phase is configured in the same manner as the single-phase switching circuit of FIG.

In FIG. 11, the switch circuit can be the same as the left half of FIG. 5 or FIG. 8 or another embodiment described later.

[0026]

Sixth Embodiment Next, an inverter device according to a sixth embodiment will be described with reference to FIGS. However, FIG.
13 and FIG. 14 to FIG. 22, which will be described later, the same parts as those in FIG. 1 to FIG. In FIG. 12, a first reactor L1 is connected to a common line between the first and second switching elements SW1 and SW2 and the load 2, and similarly, the third and fourth switching elements SW3 and SW4 and the load The second reactor L2 is connected to a common line between the two. Also, the first to fourth auxiliary capacitors CS1 to CS4 and the first to fourth auxiliary capacitors CS1 to CS4 connected in parallel to the first to fourth switching elements SW1 to SW4 via the first and second reactors L1 and L2. Four auxiliary diodes DL1 to DL4 are provided. CS1 to CS4 and DL1 to DL4 are arranged on the load side of the reactors L1 and L2.

As shown in FIG. 13, there is a pause between the control pulses of the first and second switching elements SW1 and SW2 and between the control pulses of the third and fourth switching elements SW3 and SW4. A gap Ta is provided.

FIG. 14 shows the waveform of each part in FIG. SW
While 1 is on and SW2 is off, circulating current Ip flows through reactor L1 in a loop of SW1-L1-DL1. Then, CS2 is charged to V in the polarity shown in the figure. C is charged to V / 2. When SW1 is turned off at t3, the current IL1 of L1 commutates immediately to C1. This current charges C1 in the reverse direction to V / 2. This causes D2 to become forward biased and the current in L1 to flow through D2. If an ON signal is applied to SW2 after D2 becomes forward biased, ZVS becomes possible. The current of L1 is fed back to the power supply in the D2-L1-DL1 loop and decreases linearly. When this current becomes 0, C
Since S2 is charged to V and an ON signal is applied to SW2, a resonance current flows due to CS1, CS2, and L1. When the resonance current flows for a period of 90 degrees of the sine wave, DL2
Is forward biased. At this time, the current of L1, which has almost reached the peak current Ip of the resonance current, is DL2-L1-SW2.
Circulating current. With the above operation, the turning off of SW1 becomes ZVS due to the effect of the charging voltage of C. The current of reactor L1 flows as a circulating current, causing conduction loss.
, SW2 are achieved by soft switching. The ON signal of SW2 is applied during the period when D2 is conducting.

[0029]

Seventh Embodiment In the inverter device of the seventh embodiment shown in FIG. 15, the auxiliary capacitors Cs1, CS2 and Cs shown in FIG.
S3 and CS4 are connected to auxiliary diodes DL1, DL2 and DL3,
Instead of connecting in parallel to DL4, the connecting point P1 between the first and second DC power supplies 1a and 1b and the connecting point P2 between the first and second auxiliary diodes DL1 and DL2 and the third and fourth points.
The auxiliary capacitors Cs1 and CS2 are connected between the auxiliary diode DL3 and the middle point P3 of the connection of the auxiliary diodes DL3 and DL4.

L when SW1 is ON and SW2 is OFF
In FIG. 1, a circulating current Ip flows in a loop of SW1-L1-DL1. And, in CS1, the polarity in the figure is up to V / 2,
C1 is also charged to V / 2. When SW1 is turned off in this state, the current of L1 is immediately commutated to C1. This current causes C1 to become V / 2 in the reverse direction.
Charged up to. When the charging proceeds to V / 2, D2 becomes forward biased, and the current of L1 is commutated to D2. SW1
OFF operation becomes ZVS by the charging voltage of C1. If an ON signal is applied to SW2 after D2 becomes conductive, SW2 can also perform ZVS. L1 commutated to D2
Is fed back to the power supply in a loop of D2-L1-DL1, and flows as a linearly decreasing current. When this current becomes 0, DL1 is cut off, and a resonance current caused by CS1 and L1 flows in a CS1-L1-SW2 loop by a voltage source charged to V / 2 of CS1. When the resonance current flows for a period of 90 degrees of a sine wave, DL2 becomes a forward bias voltage. At this time, the current of L1, which has almost reached the peak current Ip of the resonance current, is reduced by the short circuit of DL2-L1-SW2 to the circulating current. It keeps flowing. As described above, the current of the reactor flows as a circulating current and causes conduction loss of the semiconductor element and the reactor, but the switching of SW1 and SW2 is soft switching. Further, an auxiliary switch for resonance is not required. The ON signal of SW2 is D2
During the period (t3 to t4 ') during which the current is conducting.

[0031]

Eighth Embodiment The circuit of FIG. 17 differs from the circuit of FIG. 12 in that the positions of the first to fourth auxiliary diodes DL1 to DL4 and the first
This corresponds to the switching of the positions of the first to fourth switching elements SW1 to SW4 and the first to fourth main diodes D1 to D4. Therefore, in FIG. 17, the first to fourth switching elements SW1 to SW4 and the first to fourth main diodes D1 to D4 are arranged between the first and second reactors L1 and L2 and the load 2, and First and second auxiliary diodes DL1, DL2 are arranged between the first and second reactors L1, L2 and the power supplies 1a, 1b.

FIG. 18 shows the state of each part of the circuit of FIG. In the state where SW1 is ON and SW2 is OFF in FIG. 17, the current of reactor L1 is SW1-L1-DL1.
In the loop as a circulating current. At this time, CS1
Is charged with a voltage of V / 2 in the polarity shown in the figure, and C2 is charged with a voltage of V. When SW1 is turned off in this state, the current of SW1 is commutated to C1 and C2. This current causes C2 to discharge linearly and C1 to charge linearly. When the voltage of C2 becomes 0, D2 becomes forward-biased, and the current of L1 commutates to D2, is fed back to the power supply at D2-L1-DL1, and linearly decreases to 0. If an ON signal is applied to SW2 while D2 is ON,
SW2 is capable of ZVS. The current of L1 becomes 0,
When DL1 is cut off, a resonance phenomenon occurs in CS1 and L1 due to the voltage V / 2 charged in CS1, and C1
Resonant current flows in the loop of S1-L1-SW2. When this resonance current flows through a 90-degree sine wave feedback, DL2 becomes forward biased, and the current IL1 of L1, which has almost reached the peak value Ip of the resonance current, is diverted to DL2, and DL2-L1-S
It continues to flow as a circulating current in the loop of W2. The turning off of SW1 becomes ZVS by the charging voltage of C1. In the above operation, the reactor current IL1 continues to flow as a circulating current, resulting in conduction loss of the semiconductor element and the reactor. However, soft switching of SW1 and SW2 is achieved. Further, the circuit configuration is simple without having an auxiliary switch. The ON signal of SW2 is applied during the period when D2 is conducting, that is, during the period from t3 to t4 '.

[0033]

Ninth Embodiment The circuit of FIG. 19 differs from the circuit of FIG. 15 in the positions of the first to fourth auxiliary diodes DL1 to DL4 and the first to fourth switching elements SW1 to SW4 and the first.
To the position of the fourth main diode D1 to D4. That is, in FIG. 19, SW1 to SW4 and D1 to D4 are arranged on the load side of the reactors L1 and L2, and DL1 to DL4 are arranged on the power supply side of the reactors L1 and L2.

FIG. 20 shows the state of each part in FIG. SW
FIG. 3 is a waveform diagram at the time of turn-off of 1 and at the time of turn-on of SW2. In the circuit of FIG. 19, SW1 is ON and SW2 is O
When the signal of the FF is applied, the circulating current Ip of the reactor L1 flows through SW1 in a loop of SW1-L1-DL1. At this time, CS1 is V / 2 in the polarity of the figure.
And C1 is also charged to a voltage of V / 2. When SW1 is turned off in this state, the current of SW1 is commutated to C1, C1 is charged in the opposite direction, and when this voltage changes linearly and becomes -V / 2, D2 conducts.
The current of L1 is returned to the power supply in a loop of D2-L1-DL1. When this current decreases linearly from Ip to 0, DL1 is cut off. If an ON signal is applied to SW2 while D2 is conducting, ZVS of SW2
Becomes possible. When SW1 is OFF, ZVS operation is performed by the charging voltage of C1. When DL1 cuts off, C
Due to the voltage V / 2 charged in S1, a resonance phenomenon occurs in CS1 and L1, and a resonance current flows through CS1-L1-SW2. When the sinusoidal resonance current flows for 90 degrees,
DL2 becomes forward-biased, and the current that has reached the peak value Ip of the resonance current of the reactor L1 at this time is DL2-L
2- The circulating current of SW2 continues to flow. In the above operation, the reactor current continues to flow as a circulating current, resulting in conduction loss of the semiconductor element and the reactor.
, SW2 are soft-switching. Further, the circuit configuration is simplified as compared with the ZVS system having the auxiliary switch.

[0035]

Tenth Embodiment In the circuit of FIG. 21, the first to fourth switching elements SW1 to SW4 and the first to fourth main diodes D1 to D4 are connected to the power supplies 1a and 1b without passing through the reactors L1 to L4. Bridge-connected to the load 2. The first to fourth auxiliary diodes DL1 to DL4 and the first to fourth auxiliary capacitors CS1 to CS4 are connected to the reactor L1.
Are connected between the power supplies 1a and 1b and the load 2 through.

FIG. 22 shows the state when SW1 is turned off and when SW2 is turned off.
21 shows the state of each part in FIG. In the circuit shown in FIG.
2 while the OFF signal is applied to the reactor L
The current 1 flows as a circulating current in the loop of SW1-L1-DL1. In this state, C1 has V /
2, and CS2 is charged with a voltage of V. When SW1 is turned off in this state, the current of SW1 is commutated to C1, C1 is charged linearly in the opposite direction, and when charged to -V / 2, D2 conducts, and the current of L1 becomes D2 -L1.
The current returns to the power supply in the loop of -DL1 and decreases linearly. O is connected to SW2 while D2 is conducting.
If the N signal is applied, ZVS of SW2 becomes possible. When the current fed back to the power supply becomes 0, DL1 is cut off, and at this time, CS2 is charged to V and
Since W2 is ON, this voltage causes a resonance phenomenon of L2 and CS2, and a resonance current flows in a loop of CS2-L2-SW2. When the resonance current flows in a sine wave form for a period of 90 degrees, DL2 becomes forward biased. At this time, the current of L1 has almost reached the peak value Ip of the resonance current, and thereafter, the current of L1 continues to flow as a circulating current of DL2-L2-SW2. As described above, the current of the reactor continues to flow as a circulating current, and the conduction loss of the semiconductor and the reactor increases, but the soft switching of SW1 and SW2 is achieved. Further, the circuit configuration is simplified as compared with the ZVS system in which an auxiliary switch needs to be provided.

The control pulses for the first to fourth switching elements SW1 to SW4 in FIGS. 15, 17, 19 and 21 are formed in the same manner as in FIG. In each embodiment, the effect of ZVS or ZCS can be obtained with a simple circuit configuration that does not use a special switching element.

[0038]

[Modifications] The present invention is not limited to the above-described embodiment, and for example, the following modifications are possible. (1) First to fourth main switching elements SW1 to SW
4 is a PW that turns on and off multiple times during a 180-degree section
It can be driven according to M control. (2) In the circuits of FIGS. 12, 15, 17, and 19, the first to fourth switching elements SW1 to SW4 are MOSFETs with built-in diodes, and the built-in diodes are first to fourth main diodes D1 to D1. Can be used as D4. (3) FIGS. 5, 8, 12, 15, 17, and 1
9, in the case of the circuit of FIG. 21, C3, C4, L3, L4
, DL3 and DL4 can be omitted. Even in this manner, the effects of ZVS and ZCS can be obtained in the left half. (4) A diode can be added in anti-parallel to SW1 to SW4 in FIG. (5) In circuits other than FIG. 1, L1 and L2 and L3 and L4 are not electromagnetically coupled. However, these can be electromagnetically coupled as needed.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing an inverter device according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a control circuit of FIG. 1 in principle.

FIG. 3 is a voltage waveform diagram showing states at points A to D in FIG. 2;

FIG. 4 is a diagram showing a state of each unit in FIG. 1;

FIG. 5 is a circuit diagram showing an inverter device according to a second embodiment.

FIG. 6 is a diagram showing a control pulse of the switching element of FIG.

FIG. 7 is a diagram illustrating a state of each unit in FIG. 5;

FIG. 8 is a circuit diagram showing a bridge-type inverter device according to a third embodiment.

FIG. 9 is a diagram illustrating a state of each unit in FIG. 8;

FIG. 10 is a circuit diagram showing a half-bridge type inverter device according to a fourth embodiment.

FIG. 11 is a diagram showing an inverter device according to a fifth embodiment.

FIG. 12 is a circuit diagram showing an inverter device according to a sixth embodiment.

FIG. 13 is a diagram showing a control pulse of the switching element of FIG.

FIG. 14 is a diagram showing a state of each unit in FIG. 2;

FIG. 15 is a circuit diagram showing an inverter device according to a seventh embodiment of the present invention.

16 is a waveform chart showing a state of each part in FIG.

FIG. 17 is a circuit diagram showing an inverter device according to the embodiment shown in FIG. 8;

18 is a waveform chart showing a state of each part in FIG.

FIG. 19 is a circuit diagram showing an inverter device according to a ninth embodiment.

FIG. 20 is a waveform chart showing a state of each unit in FIG. 19;

FIG. 21 is a diagram showing an inverter device having the diameter shown in FIG. 10;

FIG. 22 is a waveform chart showing a state of each unit in FIG. 21;

[Explanation of symbols]

 SW1 to SW4 Auxiliary switching element C1, C2 Capacitor L1 to L4 Reactor

Claims (8)

(57) [Claims] A first DC power supply having a positive terminal and a negative terminal; a first DC power supply having a positive terminal and a negative terminal;
A second DC power supply (1b) connected to the negative terminal of the DC power supply (1a), and a second DC power supply (1b) connected between the positive terminal of the first DC power supply (1a) and one end of the load (2). First switching element (SW
1) a second switching element (SW2) connected between a negative terminal of the second DC power supply (1b) and one end of the load (2); and the first and second switching. Element (SW1, SW2)
And a first or second main diode (D1, D2) respectively connected in reverse parallel to the load and supplying a load (2) with AC power. In the inverter device, the first and second switching elements (SW1, SW2)
1 and 2 connected in reverse parallel to
Auxiliary diodes (DL1, DL2), and the first and second switching elements (SW1, SW2).
) And the first and second auxiliary diodes (DL1, D2).
L2) and first and second reactors connected in series with the first and second main diodes (D1, D2), respectively, and electromagnetically coupled to each other. (L1, L2), the first DC power supply (1a) and the second DC power supply (1a).
b) a capacitor (C1) connected between the midpoint of connection with the first main diode (D1) and the midpoint of connection with the second main diode (D2); First and second switching elements (SW1, SW2)
, For generating the first and second control pulses for driving the first control pulse, and the first and second control pulses are set to be generated alternately with a period in which the first and second control pulses partially overlap. A single-phase or multi-phase bridge-type or half-bridge type inverter device comprising a switch control circuit. 2. A first direct-current power supply (1a) having a positive terminal and a negative terminal, a positive terminal and a negative terminal, and the positive terminal is connected to the first terminal.
A second DC power supply (1b) connected to the negative terminal of the DC power supply (1a), and a second DC power supply (1b) connected between the positive terminal of the first DC power supply (1a) and one end of the load (2). First switching element (SW
1) a second switching element (SW2) connected between a negative terminal of the second DC power supply (1b) and one end of the load (2); and the first and second switching. Element (SW1, SW2)
And a first or second main diode (D1, D2) respectively connected in reverse parallel to the load and supplying a load (2) with AC power. In the inverter device, the first and second switching elements (SW1, SW2
), And first and second reactors (L1, L2) connected in parallel with the first and second main diodes (D1, D2), respectively.
And the first DC power supply (1a) and the second DC power supply (1a).
b) and a capacitor (C1) connected between a connection point between the first main diode (D1) and the second main diode (D2). One end is connected to the negative terminal of the second DC power supply (1b), and the other end is connected to the first switching element (SW).
1) and a first auxiliary diode (DL1) connected to a connection point between the first reactor (L1) and one end of which is connected to the second reactor (L2) and the second switching element (DL1). SW2), a second auxiliary diode (DL2) having the other end connected to the positive terminal of the first DC power supply (1a), and the first and second switching devices. Element (SW1, SW2)
A single-phase or multi-phase bridge type or half-bridge, wherein the switch control circuit is set so as to alternately generate first and second control pulses for driving the switch. Type inverter device. 3. The device according to claim 2, further comprising first and second auxiliary capacitors connected in parallel to said first and second switching elements. The inverter device as described. 4. A first DC power supply (1a) having a positive terminal and a negative terminal, a positive terminal and a negative terminal, wherein the positive terminal is the first terminal.
A second DC power supply (1b) connected to the negative terminal of the DC power supply (1a), and a second DC power supply (1b) connected between the positive terminal of the first DC power supply (1a) and one end of the load (2). The first main switching element (S
W1), a second switching element (SW2) connected between the negative terminal of the second DC power supply (1b) and one end of the load (2), and the first and second switching. Element (SW1, SW2
), A first and a second main diode (D1, D2) respectively connected in reverse parallel to the load (2) to supply AC power to the load (2). In a half-bridge type inverter device, the first and second switching elements (SW1, SW2)
) And one end of the load (L1) connected between the connection midpoint of the first and second main diodes and one end of the load.
), And the first and second switching elements (SW1, SW2).
) And the first and second DC power supplies (1a,
1b) and the main capacitor (C
1), and the first and second switching elements (SW1, SW2).
) With the first and second auxiliary capacitors (Cs1, Cs2) connected in parallel via the reactor (L1).
And the first and second switching elements (SW1, SW2).
) Are connected in parallel in the reverse direction via the reactor (L1) to the first and second auxiliary diodes (DL1).
, DL2), and a switch control circuit that alternately generates first and second control pulses for driving the first switching elements (SW1, SW2) with a predetermined time interval. A single-phase or multi-phase bridge-type inverter device. 5. A first series having a positive terminal and a negative terminal.
A power supply (1a), a positive terminal and a negative terminal, and the positive terminal is connected to the first terminal.
DC power supply connected to the negative terminal of the DC power supply (1a)
A power supply (1b), a positive terminal of the first DC power supply (1a) and a load (2);
A first main switching element (S
W1), the negative terminal of the second DC power supply (1b) and the load
A second switching element connected between one end of (2) and
(SW2) and the first and second switching elements (SW1, SW2).
) Are connected in reverse parallel to the first and second
A single or multi-phase main power supply (D1, D2) for supplying AC power to the load (2)
Of bridge type or half bridge type inverter
And the first and second switching elements (SW1, SW2).
) And the first and second main diodes (D1, D2).
) And one end of the load (2).
Reactor (L1) and the first and second switching elements (SW1, SW2).
) And the first and second DC power supplies (1a,
1b) and the main capacitor (C
1) and the first and second switching elements (SW1, SW2).
) In the opposite direction via the reactor (L1).
A first and a second auxiliary diode (DL1) connected to a row
, DL2) and the connection midpoint between the first and second DC power supplies (1a, 1b).
And the first and second auxiliary diodes (DL1, DL2).
) And an auxiliary capacitor (Cs
1) and turn on the first switching elements (SW1, SW2)
The first and second control pulses for driving are driven for a predetermined time.
A single-phase or multi-phase bridge-type inverter device comprising: a switch control circuit (5) that alternately generates with a gap . 6. A first series having a positive terminal and a negative terminal.
A power supply (1a), a positive terminal and a negative terminal, and the positive terminal is connected to the first terminal.
DC power supply connected to the negative terminal of the DC power supply (1a)
A power supply (1b), a positive terminal of the first DC power supply (1a) and a load (2);
A first main switching element (S
W1), the negative terminal of the second DC power supply (1b) and the load
A second switching element connected between one end of (2) and
(SW2) and the first and second switching elements (SW1, SW2).
) Are connected in reverse parallel to the first and second
A single or multi-phase main power supply (D1, D2) for supplying AC power to the load (2)
Of bridge type or half bridge type inverter
And the first and second switching elements (SW1, SW2).
) First and second main capacitors connected in parallel
(C1, C2) and one end thereof is connected to the first and second main capacitors (C1, C2).
2) the reactor (L1) connected to the connection midpoint, the other end of the reactor (L1), and the first and second shafts.
Of the power supply (1a, 1b)
An auxiliary capacitor (Cs1) and the first and second switching elements (SW1, SW2).
) In the opposite direction via the reactor (L1).
A first and a second auxiliary diode (DL1) connected to a row
, DL2) and the first switching elements (SW1, SW2) are turned on.
The first and second control pulses for driving are driven for a predetermined time.
A single-phase or multi-phase bridge-type inverter device comprising: a switch control circuit (5) that alternately generates with a gap . 7. A first series having a positive terminal and a negative terminal.
A power supply (1a), a positive terminal and a negative terminal, and the positive terminal is connected to the first terminal.
DC power supply connected to the negative terminal of the DC power supply (1a)
A power supply (1b), a positive terminal of the first DC power supply (1a) and a load (2);
A first main switching element (S
W1), the negative terminal of the second DC power supply (1b) and the load
A second switching element connected between one end of (2) and
(SW2) and the first and second switching elements (SW1, SW2).
) Are connected in reverse parallel to the first and second
A single or multi-phase main power supply (D1, D2) for supplying AC power to the load (2)
Of bridge type or half bridge type inverter
And the first and second switching elements (SW1, SW2).
) And the first and second DC power supplies (1a,
1b) and the main capacitor (C
1) and one end thereof is connected to the first and second switching elements (SW).
Reactor (L1) connected to the midpoint of connection between SW1, SW2)
) And the first and second switching elements (SW1, SW2).
) In the opposite direction via the reactor (L1).
A first and a second auxiliary diode (DL1) connected to a row
, DL2) and the connection midpoint between the first and second DC power supplies (1a, 1b).
And the other end connected to the other end of the reactor (L1).
Turn on the auxiliary capacitor (Cs1) and the first switching elements (SW1, SW2).
The first and second control pulses for driving are driven for a predetermined time.
A single-phase or multi-phase bridge-type inverter device comprising: a switch control circuit (5) that alternately generates with a gap . 8. A first direct-current power supply (1a) having a positive terminal and a negative terminal, a positive terminal and a negative terminal, and the positive terminal is connected to the first terminal.
A second DC power supply (1b) connected to the negative terminal of the DC power supply (1a), and a second DC power supply (1b) connected between the positive terminal of the first DC power supply (1a) and one end of the load (2). First switching element (SW
1) a second switching element (SW2) connected between a negative terminal of the second DC power supply (1b) and one end of the load (2); and the first and second switching. Element (SW1, SW2)
And a first or second main diode (D1, D2) respectively connected in reverse parallel to the load and supplying a load (2) with AC power. In the inverter device, the first and second switching elements (SW1, SW2)
1 and 2 connected in reverse parallel to
Auxiliary diodes (DL1, DL2); and the first and second auxiliary diodes (DL1, DL2).
And the first and second reactors (L1, L2) connected in parallel with the first and second main diodes (D1, D2), respectively, and the first and second reactors (L1, L2). DC power supply (1a) and the second DC power supply (1a).
b) a capacitor (C1) connected between a midpoint of connection with the first main diode (D1) and a midpoint of connection with the second main diode (D2); First and second auxiliary diodes (DL1, DL2)
And the first and second reactors connected in series to the first and second reactors (L1, L2).
Auxiliary capacitors (Cs1, Cs2), and the first and second switching elements (SW1, SW2).
And a switch control circuit for generating first and second control pulses with a predetermined time interval for driving the switch on). Fubridge type inverter device.