JP3377039B2 - Power conversion device and its control 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 power converter including an inverter device for converting direct current power into alternating current power or a converter device for converting alternating current power into direct current power and a control device therefor, and in particular, power conversion with a simple circuit configuration. Belongs to a power conversion device and its control device that can reduce the electrical stress applied to the switching element for power supply.

[0002]

2. Description of the Related Art A power converter for converting power between DC-AC or AC-DC by controlling ON / OFF of a plurality of switching elements for power conversion by PWM (pulse width modulation) control has been conventionally used as an uninterruptible power supply. It is used in devices, inverters for driving induction motors, battery chargers, and the like. In particular, a resonance type power conversion device that reduces the surge voltage, surge current, switching loss, etc. generated during the switching operation of the power conversion switching element due to resonance to reduce the electrical stress received by the power conversion switching element has low noise. Has recently attracted attention as a power conversion device.

FIG. 14 shows a saw-tooth carrier wave comparison type three-phase inverter device as a conventionally used power conversion device. The three-phase inverter device shown in FIG. 14 has a DC power supply (3) connected to the DC input terminals (1, 2) and a DC input terminal (1, 2).
Main switching circuit (7) connected between 2) and the three AC output terminals (4,5,6), and the line on the AC output terminals (4,5,6) side of the main switching circuit (7) AC reactors (20, 21, 22) connected to. Main switching circuit (7)
Are three pairs of power conversion IGBTs (insulated gate bipolar transistors) (8,9; 10,11; 12,13) as a plurality of main switching elements which are bridge-connected, and 3
Main diodes (14,15; 16,17; 18,19) as main rectifiers connected between collector-emitter terminals of a pair of power conversion IGBTs (8,9; 10,11; 12,13) Composed of and.
Also, the first to sixth main gate signals V _{G1 to} V _G6 are applied to the respective gate terminals of the three pairs of power conversion IGBTs (8, 9; 10, 11; 12, 13) to provide the main switching circuit (7 ) Each power conversion IGB
A control circuit (23) as a control device for controlling the switching operation of T (8,9; 10,11; 12,13) is provided. In the three-phase inverter device shown in FIG. 14, three pairs of power conversion IGBTs (8,9; 10,11; with the first to sixth main gate signals V _{G1 to} V _G6 output from the control circuit (23). By controlling the on / off of (12, 13), the DC power supplied from the DC power supply (3) to the DC input terminals (1, 2) is converted to three-phase AC power, and the AC reactor (20, 21, 22) The three-phase AC outputs of the U-phase, V-phase and W-phase output from the three AC output terminals (4,5, 6) are supplied to a three-phase AC load or a three-phase AC system not shown respectively.

The control circuit (23) includes U-phase, V-phase, and W-phase reference voltage generators (24, 25, 26), a carrier wave generator (27), three comparators (28), and U. Phase, V phase and W phase main gate signal generators (29, 30, 31) are provided. The U-phase, V-phase and W-phase reference voltage generators (24, 25, 26) are connected to the + input terminals of each comparator (28), and the carrier wave generator (27) is-of each comparator (28). Connected to the input terminal. The output terminal of each comparator (28) is connected to the main gate signal generator (29, 30, 31) of the corresponding phase. U-phase, V-phase and W-phase main gate signal generators (29,3
The two signal output terminals (0, 31) are connected to the main switching circuit (7).
Are connected to the respective gate terminals of the three pairs of power conversion IGBTs (8,9; 10,11; 12,13).

U-phase, V-phase and W-phase reference voltage generators (24,
25,26) have a phase difference of (2/3) π [rad] with each other.
Reference voltage V of U phase, V phase and W phase_UR, V_VR, V_WRThat
Output. The carrier wave generator (27) is the frequency of the AC output.
Higher frequency (20 to 150 Hz) than (50 to 60 Hz)
kHz) Sawtooth carrier wave h is output. Sawtooth carrier h is the minimum
After increasing linearly from the value to the maximum value, the maximum
From the value to the minimum value, it drops sharply and is reset.
It The comparator (28) is a reference voltage of U phase, V phase or W phase.
V_UR, V_VR, V_WRAnd the voltage level of the sawtooth carrier h
And the U-phase, V-phase, or W-phase reference voltage V_UR, V_VR, V
_WRIs higher than the voltage level of the sawtooth carrier h,
"1", U-phase, V-phase or W-phase reference voltage V_UR, V_VR, V_WR
Is lower than the voltage level of the sawtooth carrier h,
Comparison signal P that becomes "0"_U, P_V, P_WIs output. U phase,
The V-phase and W-phase main gate signal generators (29, 30, 31) are compared
Comparison signal P of the instrument (28)_U, P_V, P_WIs 1 when the main switch
Power conversion IGBT (8,10,1) on one side of the switching circuit (7)
2) 1st, 3rd and 5th main gate signals that are turned on
V_G1, V _G3, V_G5Corresponding to each power conversion IGBT (8,10,
12) It outputs to the gate terminal and each comparison signal P_U, P_V, P_WBut
Power of the other side of the main switching circuit (7) when it is "0"
The second and the second IGBTs (9, 11, 13) for conversion are turned on.
4, sixth main gate signal V_G2, V _G4, V_G6Corresponding to each electric
Output to the gate terminal of the force conversion IGBT (9,11,13).

U-phase, V-phase and W-phase reference voltage generators (24, 2
5,26) reference voltages V _UR , V _VR , V _WR and carrier wave generator (27)
The output waveform of the sawtooth carrier h of is shown in FIG.
Output waveforms of the comparison signals P _U , P _V , and P _W of the V-phase and W-phase comparators (28) are shown in FIGS. 15 (B), (C), and (D), respectively. In addition, an operation delay or the like occurs in any one of the three pairs of power conversion IGBTs (8, 9; 10, 11, 11; 12, 13), and, for example, the pair of power conversion IGBTs (8, 9) are simultaneously turned on. In this state, the DC power supply (3) is short-circuited, so one of the power conversion IGBTs (8)
After being turned off, a delay time t _D of about several μsec (3 μsec) is provided and the other power conversion IGBT (9) is turned on. This delay time t _D is called dead time. Thus, the waveforms of the first and second main gate signals V _G1 and V _G2 output from the U-phase main gate signal generating circuit (24) are shown in FIGS. 16 (A) and 16 (B), respectively. Although illustration is omitted, V
Third and fourth main gate signals V _G3 , V _G4 output from the phase main gate signal generation circuit (25) and fifth and sixth output from the W phase main gate signal generation circuit (26). The waveforms of the main gate signals V _G5 and V _G6 are similar to those shown in FIGS. 16 (A) and 16 (B). In the following description, FIG. 16 (A) and
The dead times t _D of the first to sixth main gate signals V _{G1 to} V _G6 shown in FIG.

FIG. 17 shows an auxiliary resonant commutation arm link type three-phase inverter device as a conventional resonant power converter. In the three-phase inverter device shown in FIG.
Resonant commutation circuit between the DC input terminals (1, 2) of the three-phase inverter shown in Fig. And the AC output side of the main switching circuit (7).
(32) is connected, and the capacitors (33, 34; 35, 35, 35, 35, 35 36; 37,38) are connected. Other configurations of the main circuit are similar to those of the three-phase inverter device shown in FIG.

The resonance commutation circuit (32) includes three resonance reactors (39, 40, 41) and six commutation IGBTs (42, 43, 44, 4).
5,46,47) and diodes for commutation (48,49,50,51,52,53)
And two DC capacitors (54, 55).
One ends of the three resonance reactors (39, 40, 41) are connected to respective connection points of the three pairs of power conversion IGBTs (8, 9; 10, 11, 11; 12, 13). Six commutation IGBTs (42,43,44,45,4
6, 47) are connected in anti-series with each other. The six commutation diodes (48,49,50,51,52,53) are
Each of the commutation IGBTs (42, 43, 44, 45, 46, 47) is connected between collector-emitter terminals. The two DC capacitors (54, 55) are connected in series between the DC input terminals (1, 2). Between the other ends of the three resonance reactors (39, 40, 41) and the connection point of the two DC capacitors (54, 55), three pairs of commutation IGBTs (42, 43; 44,45; 4
6, 47) are connected respectively. Also, six IGs for commutation
BT (42, 43, 44, 45, 46, 47) is a commutation gate signal V from a commutation gate signal generator (56) provided in the control circuit (23).
On / off control is performed by _A1 , V _A2 , V _A3 , V _A4 , V _A5 , and V _A6 , and each power conversion IGBT in the main switching circuit (7)
When the switching operation of (8,9; 10,11; 12,13) is performed, the corresponding commutation IGBTs (42,43; 44,45; 46,47) are switched.

In the configuration shown in FIG. 17, an AC output terminal
The switching operation of the power conversion IGBT (8, 9) in the main switching circuit (7) corresponding to the AC output terminal (4) when the U-phase current I _U flowing in (4) is in the direction shown in the figure is as follows. On the street. One of the main switching circuits (7) for power conversion I
When the GBT (8) is off and the other power conversion IGBT (9) is on, the U-phase current I _U flows from the AC output terminal (4) to the AC reactor (20) and the other power conversion IGBT ( 9)
Through the DC power supply (3). At this time, the other capacitor (34) is discharged to approximately 0 V, and the other capacitor (34)
(33) is charged to the voltage E of the DC power supply (3). When the commutation IGBT (42) in the resonant commutation circuit (32) is turned on from this state, the DC commutation (54, 55) causes commutation I
The current I _LU flows in the direction shown in the drawing through the GBT (42), the commutation diode (49) and the resonance reactor (39), and the current flowing through the other power conversion IGBT (9) increases.

When the other power conversion IGBT (9) in the main switching circuit (7) reaches a predetermined magnitude and the other power conversion IGBT (9) is switched from the ON state to the OFF state. , The current flowing in the other power conversion IGBT (9) is switched to the current flowing in the other capacitor (34), the other capacitor (34) is charged and the one capacitor (33) is discharged. . This causes the voltage across the other capacitor (34) to rise gently from 0V,
Since the rate of increase in voltage between the collector and emitter terminals of the other power conversion IGBT (9) is suppressed, zero voltage switching (ZVS) occurs when the other power conversion IGBT (9) is turned off.

When the voltage across one capacitor (33) in the main switching circuit (7) becomes approximately 0V and the voltage across the other capacitor (34) reaches the voltage E of the DC power supply (3), The main diode (14) is turned on, and a current flows through one main diode (14). In this state, when one of the power conversion IGBT (8) is turned from the off state to the on state, no current flows in the one power conversion IGBT (8) at the time of turn-on, and the voltage between the collector and emitter terminals is also 0V. . This results in zero voltage and zero current switching (ZVS / ZCS) when one of the power conversion IGBTs (8) is turned on. In addition, the resonance reactor (3
The current I _LU flowing in 9) is regenerated by the DC capacitor (54, 55), and when the current I _LU becomes almost 0, the resonant commutation circuit (32)
The commutation IGBT (42) therein changes from the on state to the off state.

One of the power conversion IGBTs (8) in the main switching circuit (7) is in the ON state and the other power conversion IGBT (8) is in the ON state.
When the commutation IGBT (43) in the resonant commutation circuit (32) is turned on when T (9) is off, one of the power conversion I
Resonance reactor (39) from GBT (8), IGBT for commutation
DC capacitor via (43) and commutation diode (48)
The current I _LU flows through (54, 55) in the opposite direction to that shown, and the current flowing through one of the power conversion IGBTs (8) increases.

When one of the power conversion IGBTs (8) in the main switching circuit (7) reaches a predetermined magnitude when one of the power conversion IGBTs (8) is turned off from the on state. , The current flowing through one of the power conversion IGBTs (8) is switched to the current flowing through one of the capacitors (33), one of the capacitors (33) is charged and the other of the capacitors (34) is discharged. . As a result, the voltage across one capacitor (33) gradually rises from 0V,
Since the voltage increase rate between the collector and emitter terminals of one power conversion IGBT (8) is suppressed, zero voltage switching is performed when one power conversion IGBT (8) is turned off.

When the voltage across the other capacitor (34) in the main switching circuit (7) becomes approximately 0V and the voltage across the one capacitor (33) reaches the voltage E of the DC power supply (3), the other The main diode (15) is turned on and a current flows through the other main diode (15). In this state, when the other power conversion IGBT (9) is turned from the off state to the on state, no current flows through the other power conversion IGBT (9) at the time of turn-on, and the voltage between the collector and emitter terminals is also 0V. . This causes zero voltage and zero current switching when the other power conversion IGBT (9) is turned on. Further, the current I _LU flowing in the resonance reactor (39) is regenerated by the DC capacitor (54, 55), and when the current I _LU becomes almost 0, the commutation IGBT in the resonance commutation circuit (32).
(43) changes from the on state to the off state.

In the above description, the switching operation of the power conversion IGBT (8, 9) in the main switching circuit (7) corresponding to the U-phase current I _U flowing through the AC output terminal (4) has been described. V flowing to the other two AC output terminals (5,6)
Switching circuit corresponding to phase I and _W currents I _V and I _W
The switching operation of the power conversion IGBTs (10, 11; 12, 13) in (7) is also the same as above, and therefore its explanation is omitted. Note that details of the operation of the three-phase inverter shown in FIG. -97-24 (1997) "and the like.

In the three-phase inverter device shown in FIG. 17, the power conversion in the main switching circuit (7) is performed by the switching operation of the six IGBTs (42) to (47) for commutation in the resonant commutation circuit (32). Since the zero voltage and zero current switching is performed when the power IGBTs (8) to (13) are turned on or off, surge voltage, surge current and switching that occur during the switching operation of each power conversion IGBT (8) to (13) Loss can be suppressed. Therefore, it is possible to reduce the electrical stress applied to each of the power conversion IGBTs (8) to (13) in the main switching circuit (7).

[0017]

By the way, in the sawtooth carrier wave comparison type three-phase inverter device shown in FIG. 14, each power conversion IGBT (8) to (13) in the main switching circuit (7) is used.
Since the current is cut off directly by turning off the power, the surge voltage, surge current, switching loss, etc. generated at turn-off cause a large electrical stress on each power conversion IGBT (8) to (13), and at the same time switching noise is generated. To do. On the other hand, when the power conversion IGBTs (8) to (13) are turned on, there is a problem that surge voltage, surge current, switching loss, etc. occur due to reverse recovery of the other main diodes (14) to (19). It was Further, in the auxiliary resonance commutation arm link type three-phase inverter device shown in FIG. 17, the main switching circuit (7) is operated by the switching operation of each of the commutation IGBTs (42) to (47) in the resonance commutation circuit (32). Each of the power conversion IGBTs (8) to (13) in the can reduce the electrical stress, but since the same number of commutation IGBTs as the power conversion IGBTs forming the main switching circuit (7) are required,
The configuration of the main circuit becomes complicated. In addition, each commutation IGBT (4
Since a large number of circuits for generating gate signals for switching control of each of 2) to (47) are required, the number of parts of the entire device increases, and the manufacturing cost becomes high.

Therefore, it is an object of the present invention to provide a power conversion device and a control device thereof which can reduce the electrical stress applied to a main switching element for power conversion with a simple circuit configuration.

[0019]

According to a first aspect of the present invention, there is provided a power conversion device including a main switching circuit (7) connected between a DC terminal (1, 2) and an AC terminal (4,5, 6). ) And an AC reactor (20,21,22) connected to the line on the AC terminal (4,5,6) side of the main switching circuit (7).
(7) is a pair of main switching elements (8,
9; 10,11; 12,13) and multiple pairs of main switching elements (8,9; 1
(0,11; 12,13) Main rectifier element connected between both main terminals
(14,15; 16,17; 18,19) and the on / off control of multiple pairs of main switching elements (8,9; 10,11; 12,13)
Converts power between AC or AC-DC. In this power converter, a plurality of pairs of main switching elements (8,9; 10,11; 12,
13) Capacitors (33,34; 3 connected between both main terminals)
5,36; 37,38) and the AC terminals (4,
A commutation reactor (39, 40, 41) connected to the (5, 6) side and a plurality of commutation rectifying elements (58, 59; 60, 61; 62, 63) are bridge-connected and for commutation. A commutation bridge circuit (57) connected to the reactors (39, 40, 41) and each main switching element (8, 9; 10,
11; 12,13) switching operation at the time of turn-on and connected between both output terminals of the commutation bridge circuit (57), and one output terminal of the commutation bridge circuit (57) From the first clamp rectifying element (65) connected from the DC terminal (1, 2) to one of the DC terminals (1, 2).
The second clamp rectifying element (66) is connected from the other side of 2) toward the other output terminal of the commutation bridge circuit (57).

The main switching element (8,9; 10,11; 12,13) is in a state in which a forward current flows.
When (8,9; 10,11; 12,13) is turned off, the current flowing in the main switching element (8,9; 10,11; 12,13) becomes
3,34; 35,36; 37,38) and the condenser (33,34; 35,36; 3
The voltage across 7,38) gradually rises from 0V. That is, the voltage rise rate between both main terminals of the main switching element (8,9; 10,11; 12,13) is suppressed by charging the capacitor (33,34; 35,36; 37,38), and the main switching Element (8,9; 10,11; 12,
Since the voltage between both main terminals of 13) gradually rises from 0 V, zero voltage switching is performed when the main switching elements (8,9; 10,11; 12,13) are turned off. Also, when the commutation switching means (64) is in the ON state, the main rectifying element (14, 1
5; 16,17; 18,19) turns on the corresponding main switching element (8,9; 10,11; 12,13) during the conducting period, immediately after turn-on the commutation reactor (39,40, 41), because the current flows through the main rectifier (14,15; 16,17; 18,19) via the commutation bridge circuit (57) and the commutation switching means (64),
No current flows through the main switching elements (8, 9; 10, 11, 11; 12, 13), and the voltage between both main terminals is 0V. This results in zero voltage and zero current switching when the main switching elements (8,9; 10,11; 12,13) are turned on. Therefore, it is possible to suppress surge voltage, surge current, switching loss, etc. generated by the abrupt switching operation of the main switching elements (8, 9; 10, 11; 12, 13). Therefore, the main switching elements (8, 9; 10, 11, 11; 12, for power conversion have a simple circuit configuration including one commutation switching means (64).
It is possible to reduce the electrical stress that 13) receives. Further, the residual energy of the commutation reactor (39, 40, 41) is the first energy after the commutation switching means (64) is turned off.
Since it is regenerated to the DC terminal (1, 2) side through the second clamp rectifying elements (65) and (66), there is no loss.

In the power converter of the invention according to claim 1, the first snubber capacitor (75) connected to one end of the commutation switching means (64) and the commutation switching means (64).
A second snubber capacitor (76) connected to the other end of
A snubber rectifying element (77) connected between the first snubber capacitor (75) and the second snubber capacitor (76),
The second snubber capacitor (76) and the snubber rectifying element (7
The first regeneration rectifier (78) and the first regeneration reactor (79) connected in series from the connection point of 7) toward one of the DC terminals (1, 2), and the DC terminals (1, 2). A second regenerative rectifying element (8) connected in series from the other side of 2) toward the connection point of the first snubber capacitor (75) and the snubber rectifying element (77).
0) and a second regeneration reactor (81).

When the commutation switching means (64) is turned on, the commutation switching means (64), the second snubber capacitor (76), the first regeneration rectifying element (78), and the first regeneration reactor ( 79), the DC power supply (3), the second regenerative reactor (81), the second regenerative rectifying element (80), and the first snubber capacitor (75) form a resonance circuit,
And the second snubber capacitors (75, 76) are discharged and the voltage across each of them drops to about 0V. When the commutation switching means (64) is turned off, the current flowing through the commutation switching means (64) causes the first snubber capacitor (75), the snubber rectifying element (77), and the second snubber capacitor (76). ), The first and second snubber capacitors (75, 76) are charged by the current, and the voltage across each of them gradually rises from 0V. Therefore, zero voltage switching is performed when the commutation switching means (64) is turned off. Therefore, the electrical stress applied to the switching means (64) due to the abrupt switching operation of the commutation switching means (64) can be reduced.

According to a second aspect of the power converter of the present invention, the commutation switching means (64) includes a snubber capacitor (82) connected between both output terminals of the commutation bridge circuit (57).
The first connected in series to both ends of the snubber capacitor (82)
Commutation switching element (83) and first regenerative rectification element (84), first commutation switching element (83) and first
(85) and a second regenerative rectifying element (86) as a second commutation switching element connected in series at both ends of the series connection circuit of the regenerative rectifying element (84) and the first commutating element It is connected between the connection point of the switching element (83) and the first regenerative rectifying element (84) and the connection point of the second commutation switching element (85) and the second regenerative rectifying element (86). With a regenerative reactor (87), the first and second commutation switching elements (83,85) switch simultaneously when the main switching elements (8,9; 10,11; 12,13) are turned on. Be operated.

First and second commutation switching elements (8
3,85) is turned on at the same time, the resonance circuit is formed in the path of the first commutation switching element (83), the snubber capacitor (82), the second commutation switching element (85) and the regenerative reactor (87). Therefore, the snubber capacitor (8
2) is discharged and the voltage across it drops to approximately 0V, and energy is stored in the regenerative reactor (87). When the voltage across the snubber capacitor (82) becomes approximately 0 V, the regenerative reactor (87) and the first commutation switching element (8
3) and the path of the second regenerative rectifying element (86) and the current circulating in the path of the regenerative reactor (87), the first regenerative rectifying element (84) and the second commutation switching element (85) Flows. When the first and second commutation switching elements (83, 85) are turned off at the same time, the current flowing in the first commutation switching element (83) causes the first regenerative rectifying element (84) and the snubber capacitor. It switches to the current flowing through the route of (82). Similarly, the current flowing in the second commutation switching element (85) is switched to the current flowing in the path of the snubber capacitor (82) and the second regenerative rectifying element (86). At this time, the snubber capacitor (82) is charged by the currents flowing through the two paths and the voltage across the snubber capacitor gradually rises from 0V, so that the first and second commutation switching means (83, 85). Zero voltage switching is performed at the time of turn-off. Therefore, it is possible to reduce the electrical stress applied to the first and second commutation switching means (83, 85) due to the abrupt switching operation of the switching means (83, 85).

A power converter according to a third aspect of the invention is a main switching circuit (7) and commutation switching means (64).
The controller (23) for controlling the switching operation of the sawtooth carrier wave (23) is a sawtooth carrier that proportionally increases linearly from a minimum value to a maximum value and then suddenly drops from the maximum value to the minimum value to reset. Commutation that controls the switching operation of the commutation switching means (64) in synchronization with the reset timing of the carrier wave generator (27) that outputs (h) and the sawtooth carrier wave (h) of the carrier wave generator (27). Gate signal generator (56) and reference voltage generator (24,25,26) that generates reference voltage (V _UR , V _VR , V _WR ).
And a current detector (68,69,70) for detecting the current flowing in the AC terminals (4,5,6), and a detection current (I _U ,
I _V , I _W ) current sign signal (S _U , S _V , S _W ) corresponding to the direction of current sign detector (71) and current sign detector (71) current sign signal (S _U , S _V , S _W ), the sawtooth carrier (h) output from the carrier generator (27) is in-phase or anti-phase to form a corrected carrier (h _U1 , h _V1 , h _W1 ). Corrected carrier generator (72,73,7
4) and the corrected carrier (h, h) from the corrected carrier generator (72, 73, 74).
_U1 , h _V1 , h _W1 ) and the reference voltage (V _UR , V _VR , V _WR ) from the reference voltage generator (24,25,26)
8) output (P _U , P _V , P _W )
Main gate signals (V _G1,, V _G2 ; V _G3 , V _G4 ; V to (8,9; 10,11; 12,13)
_G5 , V _G6 ) and a main gate signal generator (29, 30, 31).

A sawtooth carrier wave (h) that rises proportionally linearly from the minimum value to the maximum value and then suddenly drops from the maximum value to the minimum value to reset the current (I) flowing through the AC terminals (4,5, 6). _U ,
I _V , I _W ) Corresponding carrier direction
(h _U1 , h _V1 , h _W1 ), and this corrected carrier wave (h _U1 , h _V1 , h _W1 ).
And the reference voltage (V _UR , V _VR , V _WR ) comparison output (P _U , P _V , P _W ) to the main gate signal (V _G1,, V _G2 ; V _G3 , V _G4 ; V _G5 , V _G6 ). As a plurality of pairs of main switching elements (8,9; 10,11; 12,13), a plurality of pairs of main switching elements (8,9; 10,11; 12,1)
The turn-on timing of 3) is synchronized with the reset timing of the sawtooth wave carrier (h). As a result, when the main switching elements (8,9; 10,11; 12,13) are turned on, the commutation gate signal generator (56) controls the switching operation of the commutation switching means (64). element
When the (8,9; 10,11; 12,13) is turned on, the switching operation can be performed with zero voltage and zero current.

According to a fourth aspect of the present invention, there is provided a control device (23) for a power conversion device, comprising: fixed pulse signal generator for outputting P) and (88), the current sign signal (S _U of the current code detector (71), S _V, when S _W) is in the first output value, the main switching circuit (7 ) The output signal of the comparator (28) for the main switching element (8, 10, 12) on one side
(P _U , P _V , P _W ) as one main gate signal (V _G1 , V _G3 , V _G5 ) and the other main switching element (9, 11, 1)
Fixed pulse signal of fixed pulse signal generator (88) for 3)
(P) is output as the other main gate signal (V _G2 , V _G4 , V _G6 ),
When the current sign signal (S _U , S _V , S _W ) of the current sign detector (71) has the second output value, the main switching element (8,10,12) on one side of the main switching circuit (7) The fixed pulse signal (P) of the fixed pulse signal generator (88) to one of the main gate signals (V _G1 ,
V _G3 , V _G5 ), and outputs the output signal (P _U , P _V , _{V of} the comparator (28) to the other main switching element (9,11,13).
A main gate signal generator (89, 90, 91) that outputs P _W ) as the other main gate signal (V _G2 , V _G4 , V _G6 ).

The current code signal (S) of the current code detector (71)_U,
S_V, S_W) Is the first output value, the main switching circuit (7)
One side main switching element (8,10,12) is comparator (28)
Output signal (P_U, P_V, P_W), The on / off control
The main switching element (9, 11, 13) on the other side
Fixed pulse signal (P) of the pulse signal generator (88)
ON / OFF is controlled by the loose width. Also, current sign detector
(71) current sign signal (S_U, S_V, S _W) Is the second output value,
One side main switching element (8,10,12) is a fixed pulse signal.
Fixed pulse by the fixed pulse signal (P) of the signal generator (88)
ON / OFF control by width and main switching circuit
The main switching element (9, 11, 13) on the other side of (7) is the comparator (2
8) Output signal (P_U, P_V, P_W), The on / off control is performed.
Here, the output signal (P_U, P_V, P_W) Rising
Edges of each main switching element (8,9; 10,11; 12,13)
Carrier wave is generated because the timing of turn-on is almost the same.
Of the sawtooth wave carrier (h) output from the device (27).
Sync to ming. Therefore, the fixed pulse signal generator
The rising edge of the fixed pulse signal (P) output from (88)
Dead time (t
_D) Can be secured. Therefore, the main switching circuit (7)
Main switching elements on one side and the other (8,10,12; 9,11,
One and the other main gate signal (V_G1, V_G3, V
_G5; V_G2, V_G4, V_G6) Each of the dead time (t_D) Is added
Since the means is unnecessary, the configuration of the control device (23) can be simplified.
Wear.

According to a fifth aspect of the present invention, there is provided a control device (23) for a power conversion device, wherein a fixed pulse signal having a constant pulse width ( fixed pulse signal generator for outputting P) and (88), the current sign signal (S _U of the current code detector (71), S _V, when S _W) is in the first output value, the main switching circuit (7 ) The output signal of the comparator (28) for the main switching element (8, 10, 12) on one side
(P _U , P _V , P _W ) is output as one main gate signal (V _G1 , V _G3 , V _G5 ), and only one of the current code signals (S _U , S _V , S _W ) When the current sign is the first output value, the fixed pulse signal (P) of the fixed pulse signal generator (88) is applied to the other main switching element (9, 11, 13) of the other phase of the corresponding phase. When the current code signal (S _U , S _V , S _W ) of the current code detector (71) is the second output value, the current code signal (V _G2 , V _G4 , V _G6 ) is output. Main switching element (8,10,12) on one side of the corresponding phase of the main switching circuit (7) when only one current sign is the second output value among S _U , S _V , S _W ). With respect to the fixed pulse signal generator (88) outputs the fixed pulse signal (P) as one of the main gate signals (V _G1 , V _G3 , V _G5 ), and the other main switching element (9, 11, 13), the output signal (P _U , P _V , P _W ) of the comparator (28) is transferred to the other main gate signal (V _G2 , V _{G 4} , V _G6 ) and a main gate signal generator (92, 93, 94).

The current code signal (S _U ,
When S _V , S _W ) is the first output value, the main switching circuit (7)
One side main switching element (8,10,12) is comparator (28)
ON / OFF control is performed by the output signals (P _U , P _V , P _W ), and only one of the current code signals (S _U , S _V , S _W ) has the first output value of the first output value. Sometimes the main switching element on the other side of the relevant phase is the fixed pulse signal of the fixed pulse signal generator (88).
On / off control is performed with a constant pulse width by (P). When the current code signal (S _U , S _V , S _W ) of the current code detector (71) is the second output value, one of the current code signals (S _U , S _V , S _W ) However, when the current sign is the second output value, the main switching element on one side of the corresponding phase of the main switching circuit (7) has a constant pulse width due to the fixed pulse signal (P) of the fixed pulse signal generator (88). Is turned on and off by the main switching device (9, 11, 13) on the other side, and the output signal of the comparator (28)
ON / OFF control is performed by (P _U , P _V , P _W ). This allows
Since the current flowing through the commutation reactor (39, 40, 41) becomes small when the commutation switching means (64) is in the ON state,
The electrical stress received during the switching operation of the plurality of main switching elements (8, 9; 10, 11; 12, 13) forming the main switching circuit (7) can be further reduced.

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment in which a power conversion device according to the present invention is applied to a three-phase inverter device will be described below with reference to FIGS.
It will be described with reference to FIG. However, in these drawings, FIG.
Portions substantially the same as those shown in FIGS. 4 to 17 are designated by the same reference numerals, and the description thereof will be omitted. As shown in Figure 1,
The three-phase inverter device according to the present embodiment includes a resonant commutation circuit (32) of the three-phase inverter device shown in FIG. 17 and three commutation reactors (39, 40, 41) connected in a bridge. Six diodes for commutation (58,59,60,6 as rectifiers for commutation)
1, 62, 63), a commutation bridge circuit (57), a commutation IGBT (64) as commutation switching means, and a first clamp diode as a first clamp rectifying element.
(65) and a second clamp diode (66) as a second clamp rectifying element, changed to a resonant commutation circuit (67) and supplied to the AC output terminals (4,5, 6) U-phase, V-phase and W-phase for detecting currents I _U , I _V and I _W of U-phase, V-phase and W-phase
The feature is that the phase current detectors (68, 69, 70) are provided on the output line of each phase between the AC output side of the main switching circuit (7) and each AC reactor (20, 21, 22). is there. One end of the three resonance reactors (39, 40, 41) has three pairs of power conversion IGBTs.
It is connected to each connection point of T (8,9; 10,11; 12,13). The other ends of the three resonance reactors (39, 40, 41) are connected to the three input terminals of the commutation bridge circuit (57). One and the other output terminals of the commutation bridge circuit (57) are connected to the collector terminal and the emitter terminal of the commutation IGBT (64), respectively. The first clamp diode (65) is connected from one output terminal of the commutation bridge circuit (57) to the DC input terminal.
Connected toward (1). The second clamping diode (66) is connected from the DC terminal (2) toward the other output terminal of the commutation bridge circuit (57). Other configurations of the main circuit are similar to those of the conventional three-phase inverter device shown in FIG.

Further, the control circuit (23) of the three-phase inverter device of the present embodiment includes the current sign detector (71) and the corrected carrier wave generators (72, 73, 74) for the U phase, V phase and W phase. ) Is added to the control circuit (23) of the three-phase inverter device shown in FIG.
The current sign detector (71) detects that the detection currents I _U , I _V , and I _W of the U-phase, V-phase, or W-phase current detectors (68, 69, 70) are in the positive direction (from the power supply to the load). The current code signals S _U , S _V , and _SW that are "1" in the case of the direction) and "0" in the case of the negative direction (the direction from the load to the power supply) are output. U-phase, V-phase and W-phase correction carrier generator (72, 73, 74), the current sign signal S _U of the current code detector (71), S _V, S _W is when the "1" carrier generator Bowl (2
7) The sawtooth carrier wave in phase with the sawtooth carrier wave h, and when the current code signals S _U , S _V , and _SW are “0”, the sawtooth carrier wave h is opposite in phase to the sawtooth carrier wave h of the carrier wave generator (27). Corrected carrier wave h _U1 , h that becomes carrier wave
_V1 and h _W1 are formed. The comparator (28) is a U-phase, V-phase or W-phase.
The levels of the reference voltages V _UR , V _VR , V _WR of the phases and the voltage levels of the corrected carrier waves h _U1 , h _V1 , h _W1 of the U phase, V phase or W phase are respectively compared, and the U phase, V phase or W phase is compared. Phase reference voltage V _UR , V _VR ,
Corrected carrier wave h _U1 , whose V _WR level is U phase, V phase or W phase,
If it is higher than the voltage level of h _V1 , h _W1 , “1”, U phase,
The levels of the V-phase or W-phase reference voltages V _UR , V _VR , and V _WR are U
Comparison signals P _U , P _V , P _{W which} are “0” when the voltage levels are lower than the voltage levels of the corrected carrier waves h _U1 , h _V1 , h _W1 of the V, V or W phase
Is output. The commutation gate signal generator (56) generates a commutation gate signal V _A for controlling the switching operation of the commutation IGBT (64) in synchronization with the reset timing of the sawtooth carrier wave h of the carrier wave generator (27). To do. Other configurations are shown in FIG.
This is the same as the control circuit (23) of the conventional three-phase inverter device shown in FIG.

The waveform of the sawtooth carrier wave h of the carrier wave generator (27) having the above structure is shown in FIG. Further, the waveform of the U-phase reference voltage V _UR and the corrected carrier wave h _U1 , the V-phase reference voltage V _U
The waveforms of _VR and the corrected carrier wave h _{V1 and} the waveforms of the W-phase reference voltage V _WR and the corrected carrier wave h _W1 are shown in FIGS. 2B, 2C and 2C, respectively.
It is shown in (D). The waveforms of the U-phase, V-phase, and W-phase AC output currents I _U , I _V , and I _W are shown in FIG.
(71) U-phase output from, V-phase and W-phase current sign signal S _U, S _V, respectively the waveform of S _W Figure 2 (F), (G) and (H)
Shown in. Also, the U phase output from the comparator (28) for each phase,
The waveforms of the V-phase and W-phase comparison signals P _U , P _V , and P _W are shown in FIGS. The waveform of the flow gate signal V _A is shown in FIG.
Shown in (L). Furthermore, the switching currents I _T1 , I _T2 , I _T3 , I _T4 , flowing between the collector and emitter terminals of the power conversion IGBTs (8, 9;
The waveforms of I _T5 and I _T6 are shown in FIGS. 3 (A), (B), (C), and FIG.
Shown in (D), (E) and (F). 2 and 3, t
₀ ~t ₃₆ shows the reset timing of the sawtooth carrier wave h the voltage of the sawtooth carrier wave h abruptly changes from the maximum value to the minimum value.

Next, when the U-phase, V-phase, and W-phase currents I _U , I _V , and I _W supplied to the AC output terminals (4,5, 6) are in the directions shown, that is, I _U The operation of the main circuit of the three-phase inverter shown in FIG. 1 when <0, _IV > 0, _IW > 0 will be described based on the waveform diagram shown in FIG. However, the period from time X ₁ to X ₄ shown in FIG. 4 is sufficiently shorter than the cycle of the sawtooth carrier wave h output from the carrier wave generator (27) (for example, 1/20 of the cycle of the sawtooth carrier wave h). To about 1/10), and changes in the currents I _U , I _V , and I _W of each phase during this period are ignored. 4 (A)-
In (F), the negative-direction components of the currents I _{T1 to} I _T6 flowing between the collector-emitter terminals of the power conversion IGBTs (8) to (13) in the main switching circuit (7) are antiparallel. The current flowing through each of the main diodes (14) to (19) connected to is shown. Further, since I _U <0, I _V > 0, I _W > 0,
Time X ₂ shown in FIG. 4 corresponds to the carrier wave generator shown in FIGS. 2 and 3.
This coincides with the reset timing of the sawtooth wave carrier h in (27).

Time X₁Previously, in Fig. 4 (I), (L) and
And (N), one of the main switching circuit (7)
Each power conversion IGBT (8,11,13) is in the ON state, the other
Each power conversion IGBT (9,10,12) and resonant commutation circuit (67)
The commutation IGBTs (64) in the inside are shown in Fig. 4 (J), (K),
Current in each phase when in the OFF state as shown in (M) and (H)
I _U, I_V, I_WOne of each in the main switching circuit (7)
Through each main diode (14, 17, 19). Well
At this time, one of the main switching circuit (7)
The capacitors (33, 36, 38) discharge to almost 0V and the other capacitors
(34, 35, 37) with the polarity shown, up to the voltage E of the DC power supply (3)
It is charged.

As shown in FIG. 4 (H), when the commutation IGBT (64) in the resonant commutation circuit (67) is turned from the off state to the on state at time X ₁ , the commutation reactor (39) and the commutation Commutation diode (58) in bridge circuit (57) and commutation IG
A commutation diode (61) and a commutation reactor (40) in the commutation bridge circuit (57) and a commutation diode (63) and a commutation reactor () in the commutation bridge circuit (57) via the BT (64). Current flows to 41). At this time, as indicated by the solid line in FIG. 4G, the current I _LU flowing through the commutation reactor (39) linearly increases in the negative direction, and the commutation reactor (4
The currents I _LV and I _LW flowing in (0) and (41) rise linearly in the positive direction as shown by the broken line in FIG.
Energy is stored at (39,40,41). Along with this, one of the main diodes (14, 17,
The current flowing in 19) decreases. Current I _LU , I flowing through each commutation reactor (39, 40, 41) in the resonant commutation circuit (67)
_LV and I _LW are the currents I _U and I _{U of} each phase flowing to the AC output terminals (4,5,6).
When it becomes sufficiently larger than I _V and I _W , as shown in FIGS.
As indicated by broken lines in (F) and (F), currents I _T1 , I _T4 , I _T6 in the positive direction flow through one of the power conversion IGBTs (8, 11, 13) in the main switching circuit (7).

As shown in FIGS. 4 (I), (L) and (N), one of the power conversion IGBTs (8, 11, 13) in one of the main switching circuits (7) at time X ₂ is substantially at the same time. When the on-state is changed to the off-state, the currents I _T1 , I _T4 and I _T6 flowing through the power conversion IGBTs (8, 11, 13) are as shown by broken lines in FIGS. 4 (A), (D) and (F). To 0, and each capacitor (3
It switches to the current flowing in (3,36,38). This charges each of the capacitors (33, 36, 38) on one side,
The voltage across both ends of (3,36,38) gradually rises from 0V. That is, the voltage rise rate between the collector and emitter terminals of one of the power conversion IGBTs (8, 11, 13) is one of the capacitors (3
3,36,38) controlled by charging, each power conversion IGBT
(8,11,13) collector-emitter terminal voltage V _T1 ,
V _T4 and V _T6 gradually rise from 0 V as shown by the solid _lines in FIGS. 4 (A), (D) and (F), respectively. Therefore, the zero voltage switching is performed when the power conversion IGBTs (8, 11, 13) are turned off. One of each capacitor (33,
The capacitors (34, 35, 37) on the other side are discharged as the voltage on both ends of the capacitors (36, 38) rises, and the voltages on both ends of the capacitors gradually drop from the voltage E of the DC power supply (3). As a result, the other power conversion IGBT in the main switching circuit (7)
(9,10,12) collector-emitter terminal voltage V _T2 ,
V _T3 and V _T5 gradually drop from the voltage E of the DC power supply (3) as shown by the solid lines in FIGS. 4 (B), (C) and (E).

During the period from time X ₂ to time X ₃ , one of the capacitors (33, 36, 38) in the main switching circuit (7) is charged and one of the power conversion IGBTs (8, 11, 13) is charged. When the voltages V _T1 , V _T4 and V _T6 between the collector and emitter terminals of the DC voltage source 3 sequentially reach the voltage E of the DC power source (3) as shown by the solid _lines in FIGS. 4 (A), (D) and (F), The other capacitors (34, 35,
37) voltage across both ends, that is, the other power conversion IGBT (9,
(10, 12) collector-emitter voltage V _T2 , V _T3 , V
_T5 becomes approximately 0 V successively as indicated by the solid lines in FIGS. 4 (B), (C) and (E). At this time, each main diode of the other
(15,16,18) becomes conductive and the resonant commutation circuit (67)
The energy accumulated in each of the commutation reactors (39, 40, 41) in the inside is released through each of the other main diodes (15, 16, 18), and the currents I _LU , I _LV , I _LW flowing in the respective It gradually decreases as shown by each line in FIG.

During conduction of each of the other main diodes (15, 16, 18) in the main switching circuit (7), that is, in FIGS. 4 (B) and 4 (C).
And the other power conversion IGBT (9, 1
0, 12) during the period in which the currents I _T2 , I _T3 , and I _T5 are in the negative direction, each commutation reactor (39, The currents I _LU , I _LV , and I _LW flowing in 40, 41) decrease linearly. Along with this, the current flowing through each of the other main diodes (15, 16, 18) also decreases. At time X ₄ during the conduction period of each of the other main diodes (15, 16, 18), as shown in FIGS. 4 (J), (K) and (M), the main switching circuit
When the other power conversion IGBTs (9,10,12) in (7) are turned from the OFF state to the ON state at the same time, a current flows through the other power conversion IGBTs (9,10,12) at turn-on. _However , the voltages V _T2 , V _T3 , and V _T5 between the collector and emitter terminals are also shown in FIG.
It is approximately 0 V as shown by the solid lines in (B), (C) and (E).
Therefore, zero voltage and zero current switching is performed when the other power conversion IGBTs (9, 10, 12) in the main switching circuit (7) are turned on. At the same time,
When the commutation IGBT (64) in the resonant commutation circuit (67) is switched from the on state to the off state, the first and second clamping diodes (65) and (66) become conductive, and each commutation reactor ( The residual energy of 39, 40, 41) is regenerated to the DC power supply (3) via the first and second clamping diodes (65) and (66). Also, when the commutation IGBT (64) is turned off,
A surge voltage higher than the voltage E of the DC power supply (3) is used for commutation I
When applied between the collector and emitter terminals of the GBT (64), the first and second clamping diodes (65) and (66)
Is turned on and the voltage between the collector and emitter terminals of the commutation IGBT (64) is clamped to the voltage E of the DC power supply (3). Therefore, the voltage E of the DC power supply (3) Higher surge voltage than that. In addition, U phase,
The operation of the main circuit of the three-phase inverter shown in FIG. 1 when the directions of the V-phase and W-phase currents I _U , I _V , and I _W are directions other than those shown in the figure is the same as that described above, and a description thereof will be omitted.

In the embodiment shown in FIG. 1, each power conversion IGBT (8,9; 10,11; 12,13) in the main switching circuit (7) is used.
When turned off, each power conversion IGBT (8,9; 10,11; 12,13) by each capacitor (33,34; 35,36; 37,38) connected between collector-emitter terminals respectively. Between the collector and emitter terminals of V _T1 , V _T2 , V _T3 , V _T4 , V _T5 ,
The increase rate of V _T6 is suppressed, and each power conversion IGBT (8, 9; 1
Zero voltage switching occurs at 0,11; 12,13) turn-off. On the other hand, when each power conversion IGBT (8,9; 10,11; 12,13) in the main switching circuit (7) is turned on,
In synchronization with the reset timing of the sawtooth carrier wave h of the carrier wave generator (27) in the control circuit (23), the commutation gate signal generator (5
The switching operation of the commutation IGBT (64) in the resonance commutation circuit (67) is controlled by 6), and each power conversion IGBT (8,
9; 10,11; 12,13) Zero voltage and zero current switching at turn-on. Therefore, each power conversion IGBT (8,9; 10,11; 12,13) in the main switching circuit (7)
Since the zero voltage and zero current switching is performed at the turn-off and turn-on of each power conversion IGBT.
It is possible to suppress surge voltage, surge current, switching loss, etc., which occur due to the abrupt switching operation of (8,9; 10,11; 12,13). Therefore, each of the power conversion IGBTs (8, 9; 10, 11;
It is possible to reduce the electrical stress received by 12, 13). Further, the residual energy of the commutation reactor (39, 40, 41) is the DC power supply (3) via the first and second clamping diodes (65) and (66) after the commutation IGBT (64) is turned off. Since it is regenerated into, it is lossless.

By the way, in the embodiment shown in FIG. 1, when the commutation IGBT (64) in the resonant commutation circuit (67) is turned off, the voltage between the collector and emitter terminals changes sharply. 64) is subject to relatively large electrical stress. In order to improve this, the resonant commutation circuit (67) of the embodiment shown in FIG. 1 may be changed to the resonant commutation circuit (67) having the configuration shown in FIG. 5 or 6, for example. The resonant commutation circuit (67) of the embodiment shown in FIG. 5 is the same as the resonant commutation circuit (67) of the embodiment shown in FIG. (75) is connected, the second snubber capacitor (76) is connected to the emitter terminal of the commutation IGBT (64), and the first snubber capacitor is connected.
A snubber diode (77) as a snubber rectifying element is connected between the (75) and the second snubber capacitor (76), and the second snubber capacitor (76) and the snubber diode (7) are connected.
Connect the first regenerative diode (78) and the first regenerative reactor (79) as the first regenerative rectifying element in series from the connection point of 7) toward the + side DC input terminal (1). From the negative DC input terminal (2) to the first snubber capacitor (75)
And a second regenerative diode as a second regenerative rectifying element in series toward the connection point of the snubber diode (77)
(80) and the second regenerative reactor (81) are connected. The commutation IGBT (64) performs a switching operation at the same timing as in the embodiment shown in FIG. Other configurations of the main circuit and the control circuit (23) are similar to those of the main circuit and the control circuit (23) of the three-phase inverter device shown in FIG.

In the configuration shown in FIG. 5, time X _{1 in} FIG.
When the commutation IGBT (64) is turned on at the timing of, the commutation IGBT (64) and the second snubber capacitor (7
6), first regenerative diode (78), first regenerative reactor (79), DC power supply (3), second regenerative reactor (8)
1), the resonance circuit is formed by the path of the second regenerative diode (80) and the first snubber capacitor (75), and the first and second snubber capacitors (75, 76) are discharged, respectively. The voltage across the voltage drops to about 0V. When the commutation IGBT (64) is turned off at the timing of time X _{4 in} FIG. 4, the current flowing in the commutation IGBT (64) causes the first snubber capacitor (75), the snubber diode (77), and the second snubber diode (77). It switches to the current flowing in the path of the snubber capacitor (76) of
The current causes the first and second snubber capacitors (75,
76) is charged, and the voltage across each of them gradually rises from 0V. As a result, the voltage rise rate between the collector and emitter terminals of the commutation IGBT (64) is suppressed,
Zero voltage switching is performed when the commutation IGBT (64) is turned off. When the sum of the voltages across the first snubber capacitor (75) and the second snubber capacitor (76) exceeds the voltage E of the DC power source (3), the first and second snubber capacitors (75)
The clamping diodes (65, 66) are forward-biased and brought into conduction, and the voltage between the collector and emitter terminals of the commutation IGBT (64) is clamped to the voltage E of the DC power supply (3). The other operations of the main circuit and the control circuit (23) are similar to those of the embodiment shown in FIG. Therefore, in the embodiment shown in FIG. 5, electrical switching of the power conversion IGBTs (8) to (13) in the main switching circuit (7) is performed by the abrupt switching operations of the IGBTs (8) to (13). Resonance commutation circuit while reducing stress
Due to the abrupt switching operation of the commutation IGBT (64) in (67), it is possible to reduce the electrical stress received by the IGBT (64).

The resonant commutation circuit (67) of the embodiment shown in FIG. 6 is the same as the resonant commutation circuit (67) of the embodiment shown in FIG. 1 instead of the commutation IGBT (64). A first commutation IG serving as a first commutation switching element is connected to both ends of the snubber capacitor (82) by connecting a capacitor (82).
The BT (83) and the first regenerative diode (84) as the first regenerative rectifying element are connected in series to form a first commutation IGBT.
A second commutation IGBT (85) as a second commutation switching element and a second commutation rectification element as a second commutation switching element are provided at both ends of the series connection circuit of the T (83) and the first regenerative diode (84). The two regenerative diodes (86) are connected in series to connect the first commutation IGBT (83) and the first regeneration diode (84) to the second commutation IGBT (85) and the second commutation IGBT (85). Connect the regenerative reactor (87) to the connection point of the regenerative diode (86). The first and second commutation IGBTs (83, 85) are simultaneously switched when the power conversion IGBTs (8, 9; 10, 11, 11; 12, 13) are turned on. Also, the first and second
The switching operation timing of the commutation IGBT (83, 85) is the same as that of the embodiment shown in FIG. Other configurations of the main circuit and the control circuit (23) are similar to those of the main circuit and the control circuit (23) of the three-phase inverter device shown in FIG.

In the configuration shown in FIG. 6, time X _{1 in} FIG.
1st and 2nd commutation IGBT (83,85)
When both are turned on at the same time, the first IGBT for commutation (8
3), snubber capacitor (82), second IGBT for commutation (8
A resonance circuit is formed in the path of 5) and the regenerative reactor (87), the snubber capacitor (82) discharges, the voltage across the snubber capacitor drops to approximately 0 V, and energy is accumulated in the regenerative reactor (87). It When the voltage across the snubber capacitor (82) becomes approximately 0 V, the path of the regenerative reactor (87), the first commutation IGBT (83) and the second regenerative diode (86), and the regenerative reactor (87). ), A current circulating in the path of the first regeneration diode (84) and the second commutation IGBT (85) flows. When the first and second commutation IGBTs (83, 85) are simultaneously turned off at the timing of time X _{4 in} FIG. 4, the current flowing in the first commutation IGBT (83) causes the first regeneration diode ( 84) and snubber capacitors (82)
It switches to the current flowing through the path. Similarly, the current flowing in the second commutation IGBT (85) is the snubber capacitor.
(82) and the current flowing through the path of the second regeneration diode (86). At this time, the snubber capacitor (82) is charged by the currents flowing through the above two paths, and the voltage across the snubber capacitor gradually rises from 0 V. Therefore, the first and second commutation IGBTs (83, 85) The voltage rise rate between the collector and emitter terminals is suppressed, and the first and second commutation IGs are used.
Zero voltage switching is performed when the BT (83, 85) is turned off. When the voltage across the snubber capacitor (82) exceeds the voltage E of the DC power supply (3), the first and second clamping diodes (65, 66) are forward biased and become conductive, and the commutation IGBT ( The voltage between the collector and emitter terminals of 64) is clamped to the voltage E of the DC power supply (3). The other operations of the main circuit and the control circuit (23) are similar to those of the embodiment shown in FIG. Therefore, in the embodiment shown in FIG. 6, electrical switching of the power conversion IGBTs (8) to (13) in the main switching circuit (7) is performed by the abrupt switching operations of the IGBTs (8) to (13). It is possible to reduce the stress and also to reduce the electrical stress received by the first and second commutation IGBTs (64) in the resonant commutation circuit (67) due to the abrupt switching operation of the IGBT (64). Become.

Further, the embodiment shown in FIG. 1 can be modified. For example, in the three-phase inverter device of the embodiment shown in FIG. 7, the control circuit of the three-phase inverter device shown in FIG.
A fixed pulse signal generator (88) is added in (23), and the main gate signal generators (29, 30, 31) of U phase, V phase and W phase in the control circuit (23) shown in FIG. 1 are added. each phase of the current sign signal S _U of the current code detector _{(71), S V, S} W and a fixed pulse signal generator (88) of the fixed pulse signal main gate signal V _G1 of each phase on the basis of the P, V
_The U-, V-, and W-phase main gate signal generators (89, 90, 91) for generating _G2 ; V _G3 , V _G4 ; V _G5 , V _G6 are changed. The fixed pulse signal generator (88) outputs a fixed pulse signal P having a constant pulse width in synchronization with the reset timing of the sawtooth wave carrier h of the carrier wave generator (27). Fixed pulse signal generator
The pulse width of the fixed pulse signal P output from (88) is slightly narrower than the pulse width of the commutation gate signal V _A of the commutation gate signal generator (56). Further, U-phase, V-phase and W-phase of the main gate signal generator (89, 90, 91), when the current sign signal S _U of the current code detector (71), S _V, S _W is "1" , The output signals P _U , P _V , P _W of the comparator (28) to one of the power conversion IGBTs (8, 10, 12) on one side of the main switching circuit (7) are connected to one of the main gate signals V _G1 , The fixed pulse signal P of the fixed pulse signal generator (88) is output to the other side power conversion IGBT (9, 11, 13) as the other main gate signal V _G2 , V _G3 , V _G5 .
Output as V _G4 and V _G6 . Conversely, current sign detector (71)
The current sign signal S _U, S _V, when S _W is "0", one side of the power conversion IGBT of the main switching circuit (7) (8, 10, 12)
Against the fixed pulse signal P of the fixed pulse signal generator (88)
_Is output as one of the main gate signals V _G1 , V _G3 , V _G5 , and the output signals P _U , P _V , P _W is output as the other main gate signals V _G2 , V _G4 , and V _G6 . Other configurations of the main circuit and the control circuit (23) are similar to those of the main circuit and the control circuit (23) of the three-phase inverter device shown in FIG.

Carrier wave generator (27) in the configuration shown in FIG.
Waveform of sawtooth carrier h, U-phase reference voltage V_URAnd correction
Wave h_U1Waveform, V phase reference voltage V_VRAnd the corrected carrier wave h
_V1Waveform, W-phase reference voltage V_WRAnd the corrected carrier wave h_W1Wave of
Type, U-phase, V-phase and W-phase AC output current I_U, I_V, I_Wof
Waveform, commutation gate signal V of commutation gate signal generator (56)_A
Waveforms of FIG. 8 (A), (B), (C), (D), (E) and
And (F). It is also output from the current sign detector (71).
U-phase, V-phase, and W-phase current sign signals S_U, S_V, S _WWave of
The shapes are shown in FIGS. 9 (A), (B) and (C) respectively, and the U phase, V
Phase and W phase comparison signal P_U, P_V, P_WWaveform of each
9 (D), (E) and (F). Furthermore, U phase, V phase and W
Main gate signal generator for each phase (89, 90, 91)
Issue V_G1, V_{G 2}, V_G3, V_G4, V_G5, V_G6Waveform of each
9 Shown in (G), (H), (I), (J), (K) and (L), fixed
The fixed pulse signal P of the pulse signal generator (88) is shown in Fig. 9 (M).
Show. 8 and 9, t₀~ T₃₆Is a sawtooth carrier
Sawtooth transfer in which the voltage of h changes rapidly from the maximum value to the minimum value
The timing of resetting the wave h is shown. In addition, each power conversion
Collector-emitter voltage V for IGBTs (8)-(13)
_T1~ V_T6, The power flowing through each of the power conversion IGBTs (8) to (13)
Flow I_T1~ I_T6, Flow to each commutation reactor (39, 40, 41)
Current I_LU, I_LV, I_LWAnd each power conversion IGBT (8) to (1
3) Main gate signal V_G1~ V_G6Resetting the sawtooth carrier wave h
The detailed waveforms around the timing are shown in Fig. 4.
Tick X₁Previously, each power conversion IGBT (8,11,13) was turned off.
Time point X₁For commutation IGBT (64)
When the power turns on, the IGBTs for power conversion (8, 11,
Shown in Figures 4 (A)-(N) except that 13) turns on.
It becomes similar to the waveform. Therefore, the three-phase inverter shown in FIG.
The operation of the main circuit of the data unit is also shown in FIG.
Same as the operation of the main circuit of the three-phase inverter device shown in
Therefore, detailed description of the operation is omitted.

As described above, also in the embodiment shown in FIG. 7, as in the embodiment shown in FIG. 1, the power switching IGBTs (8) to (13) of the main switching circuit (7) are turned off and turned on. Since zero voltage and zero current switching occurs at times, it is possible to obtain the same effect as that of the embodiment shown in FIG. Furthermore, in the embodiment shown in FIG. 7, the rising edges of the output signals P _U , P _V , and P _W of the comparators (28) coincide with the turn-on timings of the power conversion IGBTs (8) to (13). Therefore, it is synchronized with the reset timing of the sawtooth wave carrier wave h output from the carrier wave generator (27). Therefore, a sufficient dead time t _D can be secured by slightly delaying the rising timing of the fixed pulse signal P output from the fixed pulse signal generator (88).
Therefore, one and the other of the main gate signals V _G1 , V _G3 , V applied to the power conversion IGBTs (8, 10, 12; 9, 11, 13) on the one side and the other side of the main switching circuit (7). _G5 ; V _G2 , V _G4 ,
Since the means for adding the dead time t _D to each of the V _G6 is unnecessary, the control circuit (2
The configuration of 3) can be simplified.

In addition, the three-phase in of the embodiment shown in FIG.
In the barter device, as in the embodiment shown in FIG.
Install a fixed pulse in the control circuit (23) of the three-phase inverter shown in
In the control circuit (23) shown in Fig. 1, a signal generator (88) is added.
U-phase, V-phase and W-phase main gate signal generators (29, 30, 31)
Is the current sign signal S of each phase of the current sign detector (71)_U, S_V, S
_WAnd the fixed pulse signal P of the fixed pulse signal generator (88)
Based on the main gate signal V of each phase_G1, V_G2; V_G3, V_G4;
V_G5, V_G6Generating U-phase, V-phase and W-phase main gate signals
No. generator (92, 93, 94) has been changed. Fixed pulse signal generation
The genitals (88) generate carrier waves as in the embodiment shown in FIG.
Synchronized with the reset timing of the sawtooth wave carrier h of the device (27)
And outputs a fixed pulse signal P having a constant pulse width. Well
In addition, U-phase, V-phase and W-phase main gate signal generators (92, 93, 9
4) is the current code signal S of the current code detector (71)_U, S_V, S_W
Is "1", the voltage on one side of the main switching circuit (7) is
Output of comparator (28) for IGBT (8,10,12) for force conversion
Signal P_U, P_V, P_WTo one main gate signal V_G1, V_G3, V_G5
As the current sign signal S_U, S_V, S_Win
And the other one of the corresponding phases when the current sign is "1"
Fixed pulse for the side power conversion IGBT (9,11,13)
The fixed pulse signal P of the signal generator (88) is applied to the other main gate signal.
Issue V_G2, V_G4, V_G6Output as. Conversely, current sign detection
Current sign signal S of the device (71) _U, S_V, S_WWhen is “0”,
Stream code signal S_U, S_V, S_WThere is only one current sign in
When it is "0", the corresponding phase of the main switching circuit (7)
One side of the power conversion IGBT (8,10,12) fixed
The fixed pulse signal P of the loose signal generator (88) is applied to one main gate.
Signal V_G1, V_G3, V_G5As the main switch
Power conversion IGBT (9,11,13) on the other side of the ching circuit (7)
To the output signal P of the comparator (28)_U, P_V, P_WThe other lord
Gate signal V_G2, V_G4, V_G6Output as. Other Lord
The configuration of the circuit and control circuit (23) is the three-phase inverter shown in FIG.
It is similar to the main circuit and control circuit (23) of the data unit.

The carrier wave generator (2
7) Waveform of sawtooth carrier h, waveform of U-phase reference voltage V _UR and correction carrier h _U1 , waveform of V-phase reference voltage V _VR and correction carrier h _V1 , W-phase reference voltage V _WR and correction carrier h _W1 waveform, U-phase, V-phase, and W-phase AC output currents I _U , I _V , and I _W
Waveform, commutation gate signal V of commutation gate signal generator (56)
The waveforms of _A are shown in FIGS. 11 (A), (B), (C), (D), and FIG.
Shown in (E) and (F). Further, the U-phase, V-phase and W-phase current code signals S _U , S _V , S output from the current code detector (71).
Waveforms of _W are shown in FIGS. 12 (A), (B) and (C), respectively,
Waveforms of the U-phase, V-phase, and W-phase comparison signals P _U , P _V , and P _W are shown in FIGS. _12D , 12E, and 12F, respectively. Furthermore, U phase,
The waveforms of the main gate signals V _G1 , V _G2 , V _G3 , V _G4 , V _G5 , and V _G6 of the V-phase and W-phase main gate signal generators (92, 93, 94) are shown in FIG. ), (H), (I), (J), (K) and (L)
Shows the fixed pulse signal P of the fixed pulse signal generator (88).
Is shown in FIG. 11 and 12, t ₀
˜t ₃₆ shows the reset timing of the sawtooth carrier wave h when the voltage of the sawtooth carrier wave abruptly changes from the maximum value to the minimum value.

Next, when the U-phase, V-phase, and W-phase currents I _U , I _V , and I _W supplied to the AC output terminals (4,5, 6) are in the directions shown, that is, I _U The operation of the main circuit of the three-phase inverter shown in FIG. 10 when <0, _IV > 0, _IW > 0 will be described based on the waveform diagram shown in FIG. However, the period from time X ₁ to X ₈ shown in FIG. 13 is sufficiently shorter than the cycle of the sawtooth wave carrier h output from the carrier wave generator (27) (for example, 1/20 of the cycle of the sawtooth wave carrier h). To about 1/10), and changes in the currents I _U , I _V , and I _W of each phase during this period are ignored. FIG.
In (A) to (F), the negative-direction components of the currents I _{T1 to} I _T6 flowing between the collector and emitter terminals of the power conversion IGBTs (8) to (13) in the main switching circuit (7) are , Currents flowing in the respective main diodes (14) to (19) connected in anti-parallel. Further, since I _U <0, I _V > 0, I _W > 0, the time X ₆ shown in FIG. 13 is the reset timing of the sawtooth carrier wave h of the carrier wave generator (27) shown in FIGS. 11 and 12. Matches

Prior to time X ₁ , FIGS. 13 (H) to 13 (N)
As shown in FIG. 5, the power conversion IGBTs (8) to (13) in the main switching circuit (7) and the commutation I in the resonant commutation circuit (67)
When the GBT (64) is off, the current I _U , I _V , I _{W of} each phase
Respectively flow through each main diode (14, 17, 19) in the main switching circuit (7). Also, at this time, one of the capacitors (33, 36,
38) discharges to approximately 0V and the other capacitor (34,35,37)
Is charged to the voltage E of the DC power supply (3) with the polarity shown.

As shown in FIGS. 13 (H) and 13 (I), time X
_{In 1} , the commutation IGBT (64) in the resonant commutation circuit (67) and one of the power conversion IGBTs in the main switching circuit (7)
When T (8) is turned on from the off state, the commutation reactor (39) and the commutation diode in the commutation bridge circuit (57)
(58) and commutation IGBT (64) via commutation bridge circuit
The commutation diode (61) in (57) and the commutation reactor (4
0) and the commutation diode (6) in the commutation bridge circuit (57).
An electric current flows through 3) and the commutation reactor (41). At this time, as shown by the solid line in FIG. 13 (G), the commutation reactor (3
The current I _LU flowing in 9) gradually rises in the negative direction, and as shown by the alternate long and short dash line in the figure, the commutation reactor (40)
The currents I _LV and I _LW flowing in (41) and (41) gradually rise in the positive direction, and energy is accumulated in the commutation reactors (39, 40, 41). Along with this, the current flowing in each of the main diodes (14, 17, 19) in the main switching circuit (7) is as shown by the broken lines in FIGS. Decrease.

At time X ₂ , the current I _LV flowing through the commutation reactor (40) in the resonant commutation circuit (67) is the AC output terminal.
Becomes sufficiently larger than the current I _V of the V-phase flowing to (5),
One main diode (17) in the main switching circuit (7) reversely recovers and becomes non-conductive, one capacitor (36) is charged, and the voltage across the capacitor (36) gradually rises from 0V. For this reason, the voltage V _T4 between the collector and emitter terminals of one of the power conversion IGBTs (11) in the main switching circuit (7) gradually rises from 0 V as shown by the solid line in FIG. 13 (D). When one capacitor (36) is charged, the other capacitor (35) is discharged, and the other power conversion IGBT
The voltage V _T3 between the collector and emitter terminals of T (10) is shown in FIG.
As indicated by the solid line in (C), the voltage E of the DC power supply (3) gradually drops.

At time X ₃ , the current I _LW flowing in the commutation reactor (41) in the resonant commutation circuit (67) is the AC output terminal.
When it becomes sufficiently larger than the W-phase current I _W flowing in (6),
One main diode (19) in the main switching circuit (7) reversely recovers and becomes non-conductive, one capacitor (38) is charged, and the voltage across the capacitor (38) gradually rises from 0V. Therefore, the voltage V _T6 between the collector and emitter terminals of one of the power conversion IGBTs (13) in the main switching circuit (7) gradually rises from 0 V as shown by the solid line in FIG. 13 (F). The other capacitor (37) is discharged as one capacitor (38) is charged, and the other power conversion IGBT
The voltage V _T5 between the collector and emitter terminals of T (12) is shown in FIG.
As shown by the solid line (E), the voltage E of the DC power supply (3) gradually drops.

At time X ₄ , the main switching circuit (7)
When the other capacitor (35) in the inside is discharged to about 0V and the voltage V _T3 between the collector and emitter terminals of the other power conversion IGBT (10) becomes about 0V as shown by the solid line in FIG. 13 (C). , The other main diode (16) becomes conductive and current starts to flow.

At time X ₅ , the main switching circuit (7)
When the other capacitor (37) in the inside discharges to approximately 0V and the voltage V _T5 between the collector and emitter terminals of the other power conversion IGBT (12) becomes approximately 0V as shown by the solid line in FIG. 13 (E). , The other main diode (18) becomes conductive and current starts to flow. The currents that flow through the other main diodes (16) and (18) in the main switching circuit (7) are the power conversion IGBT (8), the commutation reactor (39), the commutation diode (58), and the commutation diode (58), respectively. Diversion IGBT (64), commutation diode
(61), commutation reactor (40) and the other main diode (1
6) and one power conversion IGBT (8), commutation reactor (39), commutation diode (58), commutation IGBT (6)
4), the commutation diode (63), the commutation reactor (41) and the other main diode (18) recirculate. Here, the power conversion IGBT (8) and the commutation IGBT (6
4) and the loss of the commutation diodes (58, 61, 63) can be ignored, the return current flowing through the above two paths is not attenuated.

As shown in FIG. 13 (I), one of the power conversion IGBTs in the main switching circuit (7) at time X ₆ .
When T (8) is switched from the ON state to the OFF state, the current I _T1 flowing through one of the power conversion IGBTs (8) becomes 0 as indicated by the broken line in FIG. 13 (A), and flows into the one capacitor (33). Switch to current. This allows the main switching circuit
One of the capacitors (33) in (7) is charged,
The voltage across (33) rises slowly from 0V. That is,
The voltage rise rate between the collector and emitter terminals of one power conversion IGBT (8) is suppressed by charging one capacitor (33), and the collector of one power conversion IGBT (8)
The voltage V _T1 across the emitter terminals gradually rises from 0 V as shown by the solid line in FIG. Therefore, zero voltage switching is performed when one of the power conversion IGBTs (8) is turned off. As the voltage across one capacitor (33) rises, the other capacitor (34) discharges, and the voltage across the other end gently drops from the voltage E of the DC power supply (3). As a result, the voltage V _T2 between the collector and emitter terminals of the other power conversion IGBT (9) in the main switching circuit (7) is the DC power supply (3) as shown by the solid line in FIG. 13 (B).
The voltage E gradually drops. At the same time, as a return current, each commutation reactor (39, 39) in the resonant commutation circuit (67).
The currents I _LU , I _LV , and I _LW flowing in 40, 41) are shown in FIG.
3 (G), the solid line, the one-dot chain line, and the broken line gradually decrease.

At time X ₇ , the main switching circuit (7)
When the voltage V _T1 between the collector and emitter terminals of one of the power conversion IGBTs (8) reaches the voltage E of the DC power supply (3) as shown by the solid line in FIG. IG
The voltage V _T2 between the collector and emitter terminals of BT (9) is shown in FIG.
As shown by the solid line of 3 (B), it becomes approximately 0V. At this time, the other main diode (15) becomes conductive and current starts to flow.

During the conduction period of the other main diodes (15, 16, 18) in the main switching circuit (7), that is, in FIG. 13 (B),
The other power conversion IGBTs shown by the broken lines in (C) and (E)
While the currents I _T2 , I _T3 , I _{T5 of} (9, 10, 12) are in the negative direction, as shown in FIG. 13 (G), each commutation reactor (39) in the resonant commutation circuit (67). , 40, 41) current I _LU , I _LV , I _LW
Gradually decreases. Along with this, the current flowing through each of the other main diodes (15, 16, 18) also decreases. At time X ₈ during the conduction period of each of the other main diodes (15, 16, ₁₈ ),
When the other power conversion IGBTs (9, 10, 12) in the main switching circuit (7) are simultaneously turned from the off state to the on state as shown in FIGS. At this time, a current flows through each of the other main diodes (15, 16, 18), so that no current flows through each of the other power conversion IGBTs (9, 10, 12) and the voltage between collector-emitter terminals V _T2 , V _T3 and V _T5 are also approximately 0 V as shown by the solid _{lines in} FIGS. 13 (B), (C) and (E). Therefore, zero voltage and zero current switching is performed when the other power conversion IGBTs (9, 10, 12) in the main switching circuit (7) are turned on. At the same time, when the commutation IGBT (64) in the resonant commutation circuit (67) is switched from the on state to the off state, the first and second clamping diodes (65) and (66) become conductive, and The residual energy of the commutation reactor (39, 40, 41) passes through the first and second clamping diodes (65) and (66), and the DC power source (3)
Regenerated to. The U-phase, V-phase, and W-phase currents I _U , I
The operation of the main circuit of the three-phase inverter shown in FIG. 10 when the directions of _V and I _W are directions other than those shown in the figure is substantially the same as that described above, and a description thereof will be omitted.

As described above, also in the embodiment shown in FIG. 10, as in the embodiment shown in FIG. 1, turn-off and turn-on of each power conversion IGBT (8) to (13) of the main switching circuit (7). Since zero voltage and zero current switching occurs at times, it is possible to obtain the same effect as that of the embodiment shown in FIG. Furthermore, in the embodiment shown in FIG. 10, the current code signals S _U , S _V , S of the current code detector (71) are used.
_{When W} is "1", the high potential side power conversion IGBT (8, 10, 12) of the main switching circuit (7) is turned on by the output signals P _U , P _V , P _W of the comparator (28). It is controlled to be off, and only one of the current code signals S _U , S _V , and S _{W has} a current code of “1”.
Power conversion IGBT on the low potential side of the corresponding phase
On / off control of (9, 11, 13) is performed with a fixed pulse width by the fixed pulse signal P of the fixed pulse signal generator (88). The current sign signal S _U of the current code detector (71), when S _V, S _W is "0", the current sign signal S _U, S _V, only one current code in the S _W is "0 When, the power conversion IGBT (8,10,12) on the high potential side of the corresponding phase of the main switching circuit (7)
Is ON / OFF controlled with a fixed pulse width by the fixed pulse signal P of the fixed pulse signal generator (88), and the power conversion IGBT (9, 11, 13) on the low potential side is connected to the comparator (28). On / off control is performed by the output signals P _U , P _V , and P _W. That is,
Since the power conversion IGBT of the other phase that does not correspond to the switching operation is stopped, the current I _LU , flowing in the commutation reactor (39, 40, 41) when the commutation IGBT (64) is in the ON state.
I _LV and I _LW are smaller than in the case shown in FIG. Therefore, as compared with the embodiment shown in FIG. 1, the electric stress received during the switching operation of the power conversion IGBTs (8) to (13) of the main switching circuit (7) can be further reduced.

The embodiment of the present invention is not limited to the above-mentioned embodiments, and various modifications can be made. For example, in each of the above-described embodiments, a mode in which an IGBT (insulated gate bipolar transistor) is used as the power conversion switching element and the commutation switching element has been described.
A MOS-FET (MOS field effect transistor), a junction bipolar transistor, a J-FET (junction field effect transistor), a thyristor or the like can also be used. In each of the above embodiments, each power conversion IGB is used.
Although the capacitors (33) to (38) are separately connected between the collector and emitter terminals of T (8) to (13),
The parasitic capacitance formed between the collector-emitter terminals of the power conversion IGBTs (8) to (13) may be used, or this parasitic capacitance may be combined with a separate capacitor. In particular, when a MOS-FET is used as each switching element, the parasitic capacitance formed between the drain and source terminals can be utilized, which has the advantage of reducing the number of parts of the main circuit. In addition, the control circuit of each of the above embodiments
Part or all of (23) may be configured by a digital integrated circuit. Further, in each of the above-described embodiments, the present invention is applied to the three-phase inverter device, but the present invention is also applied to a single-phase inverter device or a multi-phase inverter device having four or more phase outputs. Is possible. Furthermore, the present invention is not limited to an inverter device that converts DC power into AC power, but can be applied to a converter device that converts AC power into DC power.

[0062]

According to the present invention, the electrical stress applied to the main switching element for power conversion can be reduced with a simple circuit configuration, so that a low-cost, low-loss and highly-reliable power conversion device can be realized. Is possible.

[Brief description of drawings]

FIG. 1 is an electric circuit diagram showing an embodiment in which a power conversion device according to the present invention is applied to a three-phase inverter device.

FIG. 2 is a waveform diagram showing signals, voltages, and currents at various parts of the circuit shown in FIG.

FIG. 3 is a waveform diagram showing a switching current and a fixed pulse signal of each power conversion IGBT shown in FIG.

FIG. 4 is an enlarged waveform diagram showing details of the voltage and current of each power conversion IGBT shown in FIG. 1 and the current of each commutation reactor.

5 is an electric circuit diagram showing a modified embodiment of the resonant commutation circuit shown in FIG.

FIG. 6 is an electric circuit diagram showing another modified embodiment of the resonant commutation circuit shown in FIG.

FIG. 7 is an electric circuit diagram showing a modified embodiment of the present invention.

8 is a waveform diagram showing signals, voltages, and currents at various parts of the circuit shown in FIG.

9 is a waveform diagram showing signals of various parts of the circuit shown in FIG. 7 and a main gate signal of each power conversion IGBT.

FIG. 10 is an electric circuit diagram showing another modified embodiment of the present invention.

11 is a waveform chart showing signals, voltages, and currents at various parts of the circuit shown in FIG.

FIG. 12 is a waveform diagram showing signals of various parts of the circuit shown in FIG. 10 and a main gate signal of each power conversion IGBT.

13 is an enlarged waveform diagram showing details of the voltage and current of each power conversion IGBT shown in FIG. 10 and the current of each commutation reactor.

FIG. 14 is an electric circuit diagram showing a conventional saw-tooth carrier wave comparison type three-phase inverter device.

FIG. 15 is a waveform diagram showing signals at various parts of the circuit shown in FIG.

16 is an enlarged waveform diagram showing a main gate signal of the circuit shown in FIG.

FIG. 17 is an electric circuit diagram showing a conventional auxiliary resonant commutation arm link type three-phase inverter device.

[Explanation of symbols]

(1), (2) ・ ・ DC input terminal (DC terminal), (3) ・ ・ DC power supply, (4), (5), (6) ・ ・ AC output terminal (AC terminal),
(7) ・ ・ Main switching circuit, (8), (9), (10), (11), (1
2), (13) ・ ・ Power conversion IGBT (main switching element), (14), (15), (16), (17), (18), (19) ・ ・ Main diode (main rectifying element) , (20), (21), (22) ・ ・ AC reactor, (23) ・ ・ Control circuit (control device), (24), (25),
(26) ・ ・ Reference voltage generator, (27) ・ ・ Carrier generator,
(28) ・ ・ Comparator, (29), (30), (31) ・ ・ Main gate signal generator, (32) ・ ・ Resonant commutation circuit, (33), (34), (35), ( 36),
(37), (38) ・ ・ Capacitor, (39), (40), (41) ・ ・ Commutation reactor, (42), (43), (44), (45), (46), (47 ) ...
IGBT for commutation (switching element for commutation), (48),
(49), (50), (51), (52), (53) ・ ・ Commutation diode (commutation rectifier), (54), (55) ・ ・ Input smoothing capacitor, (56) ・ ・Commutation gate signal generator, (57) ・ ・ Commutation bridge circuit, (58), (59), (60), (61), (62), (63) ・ ・
Commutation diode (commutation rectifying element), (64) ・ ・ Commutation IGBT (commutation switching element), (65) ・ ・ First clamping diode (first clamping rectifying element), (66) ・-Second clamp diode (second clamp rectifier), (67) -Resonant commutation circuit, (6
8), (69), (70) ・ ・ Current detector, (71) ・ ・ Current sign detector, (72), (73), (74) ・ ・ Corrected carrier wave generator, (75) ・
-First snubber capacitor, (76) -Second snubber capacitor, (77) -Snubber diode (snubber rectifying element), (78) -First regenerative diode (first (79) ··· First regeneration reactor, (80) ··· Second regeneration diode (second regeneration rectification element), (81) ··· Second regeneration reactor ,
(82) ・ ・ Snubber capacitor, (83) ・ ・ First commutation IGBT (first commutation switching element), (84) ・ ・
A first regenerative diode (first regenerative rectifying element),
(85) · Second IGBT for commutation (second commutation switching element), (86) · Second diode for regeneration (second)
Rectifying element for regeneration), (87) ... Regeneration reactor,
(88) ・ ・ Fixed pulse signal generator, (89), (90), (91) ・ ・
Main gate signal generator, (92), (93), (94) ... Main gate signal generator

Claims (5)

(57) [Claims] 1. A main switching circuit connected between a DC terminal and an AC terminal, and an AC reactor connected to a line on the AC terminal side of the main switching circuit, wherein the main switching circuit is a bridge. A plurality of pairs of main switching elements connected to each other, and a main rectifying element connected between both main terminals of the plurality of pairs of main switching elements, respectively. −
In a power converter for converting power between AC or AC-DC, a capacitor connected between both main terminals of the plurality of pairs of main switching elements, and for commutation connected to the AC terminal side of the main switching circuit. A reactor, a commutation bridge circuit formed by bridging a plurality of commutation rectifying elements and connected to the commutation reactor, and both of the commutation bridge circuits that are switched when the main switching elements are turned on. Switching means for commutation connected between output terminals, and a first connection from one output terminal of the commutation bridge circuit toward one of the DC terminals
And a second clamp rectifying element connected from the other of the DC terminals to the other output terminal of the commutation bridge circuit, and connected to one end of the commutation switching means. Is connected between the first snubber capacitor, the second snubber capacitor connected to the other end of the commutation switching means, and the first snubber capacitor and the second snubber capacitor. Snubber rectifying element, a second regenerative rectifying element and a first regenerative rectifying element connected in series from a connection point of the second snubber capacitor and the snubber rectifying element toward one of the DC terminals. A reactor, a second regenerative rectifying element connected in series from the other of the DC terminals toward a connection point of the first snubber capacitor and the snubber rectifying element, and An electric power conversion device comprising a second regeneration reactor. 2. A main switching circuit connected between a DC terminal and an AC terminal, and an AC reactor connected to a line on the AC terminal side of the main switching circuit, wherein the main switching circuit is a bridge. A plurality of pairs of main switching elements connected to each other, and a main rectifying element connected between both main terminals of the plurality of pairs of main switching elements, respectively. −
In a power converter for converting power between AC or AC-DC, a capacitor connected between both main terminals of the plurality of pairs of main switching elements, and for commutation connected to the AC terminal side of the main switching circuit. A reactor, a commutation bridge circuit formed by bridging a plurality of commutation rectifying elements and connected to the commutation reactor, and both of the commutation bridge circuits that are switched when the main switching elements are turned on. Switching means for commutation connected between output terminals, and a first connection from one output terminal of the commutation bridge circuit toward one of the DC terminals
And a second clamp rectifying element connected from the other of the DC terminals toward the other output terminal of the commutation bridge circuit, wherein the commutation switching means includes the commutation means. A snubber capacitor connected between both output terminals of the bridge circuit, a first commutation switching element and a first regenerative rectifying element connected in series at both ends of the snubber capacitor, and the first switching element. A second commutation switching element and a second regenerative rectification element connected in series at both ends of a series connection circuit of the diversion switching element and the first regenerative rectification element, the first commutation switching element and the A regenerative reactor connected between a connection point of the first regenerative rectifying element and a connection point of the second commutation switching element and the second regenerative rectifying element; Serial first and second commutating switching elements, the power conversion apparatus which is characterized in that a switching operation simultaneously with turning on of the respective main switching devices. 3. A control device for controlling the switching operation of the main switching circuit and the commutation switching means, wherein the control device proportionally and linearly rises from a minimum value to a maximum value and then from the maximum value to the minimum value. Carrier wave generator that outputs a sawtooth wave carrier wave that rapidly drops to a reset value and a commutation gate that controls the switching operation of the commutation switching means in synchronization with the reset timing of the sawtooth wave carrier wave of the carrier wave generator. A signal generator, a reference voltage generator that generates a reference voltage, a current detector that detects a current flowing through the AC terminal, and a current that outputs a current sign signal corresponding to the direction of the detected current of the current detector. A code detector and a correction carrier that makes the sawtooth carrier output from the carrier generator in-phase or anti-phase corresponding to the current sign signal of the current sign detector. A correction carrier wave generator to be formed, a comparator for comparing the correction carrier wave from the correction carrier wave generator with the reference voltage from the reference voltage generator, and an output of the comparator to the main switching elements of the plurality of pairs. The power converter according to claim 1 or 2, further comprising a main gate signal generator that applies a gate signal. 4. A fixed pulse signal generator for outputting a fixed pulse signal having a constant pulse width in synchronism with a reset timing of a sawtooth carrier wave of the carrier wave generator, and a current code signal of the current code detector is first. When the output value is, the output signal of the comparator is output as one main gate signal to the main switching element on one side of the main switching circuit, and the fixed pulse signal is output to the main switching element on the other side. The fixed pulse signal of the generator is output as the other main gate signal, and when the current sign signal of the current sign detector has a second output value, the fixed pulse signal is fixed to the main switching element on one side of the main switching circuit. The fixed pulse signal of the pulse signal generator is output as one main gate signal, and the output signal of the comparator is supplied to the other main switching element. Claim and a main gate signal generator for outputting as the other main gate signal 3
The controller of the power converter according to. 5. A fixed pulse signal generator for outputting a fixed pulse signal having a constant pulse width in synchronism with a reset timing of a sawtooth carrier wave of the carrier wave generator, and a current code signal of the current code detector is first. When the output value is, the output signal of the comparator is output as one main gate signal to the main switching element on one side of the main switching circuit, and only one of the current sign signals has a current sign. The fixed pulse signal of the fixed pulse signal generator is output as the other main gate signal to the other main switching element of the corresponding phase at the first output value, and the current code signal of the current code detector is output. Is a second output value, and only one of the current sign signals has a second output value, the main switching element on one side of the corresponding phase of the main switching circuit when the current sign has a second output value. On the other hand, a main gate signal that outputs the fixed pulse signal of the fixed pulse signal generator as one main gate signal, and outputs the output signal of the comparator as the other main gate signal to the other main switching element. The control device for the power converter according to claim 3, further comprising a generator.