JP5724551B2 - Power conversion device and motor control device using the same - Google Patents

Description

  The present invention relates to a power conversion device and a motor control device that convert AC power and DC power from one to the other.

  2. Description of the Related Art Conventionally, in a power converter, for example, as shown in FIG. 1 of Patent Document 1, a diode bridge circuit configured by four diodes for full-wave rectification of an output voltage of an AC power supply, and a positive output terminal of the diode bridge circuit A DC load disposed between the positive output terminal and the DC load, a DC reactor disposed between the positive output terminal and the DC load, and an input side disposed between the positive output terminal and the DC reactor. Some have a transistor.

  In this device, a common connection terminal between the output terminal of the input side transistor and the input terminal of the DC reactor, an input side short-circuit diode connected between the negative side output terminal of the diode bridge circuit, a DC reactor and a DC An output side short circuit transistor disposed between the output side diode disposed between the load and the common connection terminal between the DC reactor 7 and the input terminal of the output side diode and the negative side output terminal of the diode bridge circuit And are provided.

  Here, by independently turning on and off the input side transistor and the output side short-circuit transistor, energy is stored in the DC reactor based on the output voltage from the diode bridge circuit, and energy from this DC reactor to the DC load is stored. It comes to supply. As a result, the AC power of the AC power source is converted to DC power and supplied to the DC load.

Japanese Utility Model Publication No. 5-18287

  In the above-mentioned Patent Document 1, energy can be supplied from an AC power source to a DC load via a diode bridge circuit and a DC reactor by independently turning on and off the input side transistor and the output side short circuit transistor. However, in the diode bridge circuit, two diodes are turned on when full-wave rectifying the output voltage of the AC power supply. Thereby, an ON voltage is generated as a conduction loss by two diodes.

  Therefore, in order to store energy in the DC reactor based on the output voltage from the diode bridge circuit, when the input side transistor and the output side short circuit transistor are turned on, the input side transistor, the output side short circuit transistor, and the two diodes are turned on. Thus, conduction loss occurs in these four elements. For this reason, the deterioration of the efficiency at the time of converting AC power into DC power is caused.

  Furthermore, when the inventor examined a power conversion device that converts DC power into AC power based on the above-mentioned Patent Document 1, in the power conversion device that converts DC power into AC power (see FIG. 42), the ON voltage As a result, it was found that the efficiency was deteriorated when power was converted.

  In the power conversion device of FIG. 42, the DC power of the battery 4 is converted into AC power and applied to the AC load 5 by switching the transistors Tr1 to Tr6.

  Specifically, by turning on the transistors Tr5 and Tr6, the current is passed between the two electrodes of the battery 4 through the transistor Tr6, the reactor 30, and the transistor Tr5, whereby energy is stored in the reactor 30.

  After that, with the transistors Tr5 and Tr6 turned off, a first state in which the transistors Tr1 and Tr4 are turned on among the transistors Tr1 to Tr4 and a second state in which the transistors Tr2 and Tr3 are turned on among the transistors Tr1 to Tr4 are alternately switched. carry out.

  In the first state, a current flows between the reactor 30 and the AC load 5 through the diode D6, the transistor Tr1, the transistor Tr4, and the diode D7 based on the energy stored in the reactor 30. In the second state, a current flows between the reactor 30 and the AC load 5 through the diode D6, the transistor Tr3, the transistor Tr2, and the diode D7 based on the energy stored in the reactor 30.

  For this reason, conduction loss occurs in four elements among the transistors Tr1 to Tr6 and the diodes D5 and D7. For this reason, the deterioration of the efficiency at the time of converting AC power into DC power is caused.

  From the above, it has been found that not only the power conversion device that converts AC power to DC power but also the power conversion device that converts DC power to AC power causes a reduction in the efficiency of power conversion due to conduction loss.

  An object of this invention is to provide the power converter device and the motor control apparatus which improved the efficiency of power conversion in view of the said point.

To achieve the above object, according to the first aspect of the present invention, the first to fourth switching elements (Q1p, Q2p, Q3p, Q4p) are arranged between the AC power source (2) and the DC load (3). A bridge circuit (20) composed of
A reactor (30) disposed between the bridge circuit and the positive electrode of the DC load;
A current limiting element (D1) that is disposed between the reactor and the positive electrode of the DC load and restricts current from flowing from the positive electrode side of the DC load to the reactor side;
A fifth switching element (Q5) disposed between the common connection terminal between the reactor and the current limiting element and the negative electrode of the DC load;
Charge control means (S131, S133) for controlling the first to fifth switching elements,
The first switching element (Q1p) is disposed between the positive electrode of the AC power source and the reactor,
The second switching element (Q2p) is disposed between the negative electrode of the AC power supply and the negative electrode of the DC load,
The third switching element (Q3p) is disposed between the positive electrode of the AC power source and the negative electrode of the DC load,
The fourth switching element (Q4p) is disposed between the negative electrode of the AC power supply and the reactor,
The charge control means (S133) turns on the first and third switching elements (Q1p, Q3p) and turns off the second and fifth switching elements (Q2p, Q5p) in the first charge control period. The fourth switching element (Q4p) is repeatedly turned on and off,
When the first and third switching elements are turned on and the second and fifth switching elements are turned off and the fourth switching element is turned on, current is supplied from the negative electrode of the AC power source to the fourth switching element, the reactor, Store the energy in the reactor by flowing to the positive electrode of the AC power supply through the current limiting element, DC load, and third switching element .
When the first and third switching elements are turned on and the second and fifth switching elements are turned off and the fourth switching element is turned off, the first and third switching elements are based on the energy stored in the reactor. Current flows through the switching element, current limiting element, and DC load,
Further, the charge control means (S131) turns on the second and fourth switching elements (Q2p, Q4p) and turns off the third and fifth switching elements (Q3p, Q5p) in the second charge control period. The first switching element (Q1p) is repeatedly turned on / off,
When the second and fourth switching elements are turned on and the third and fifth switching elements are turned off and the first switching element is turned on, current is supplied from the positive electrode of the AC power source to the reactor, the second, first Through the switching element, current limiting element, and DC load to the negative electrode of the AC power supply to store energy in the reactor,
Based on the energy stored in the reactor when the second and fourth switching elements are turned on and the third and fifth switching elements are turned off and the first switching element is turned off, the second and fourth switching elements are turned on. A current is allowed to flow through the switching element, the current limiting element, and the DC load.

  According to the first aspect of the present invention, when a current is passed through the reactor between the electrodes of the AC power supply, and when a current is passed through the DC load based on the energy stored in the reactor, the first to fifth Of the switching element and the current limiting element, three elements are energized.

  In the above-described power converter of Patent Document 1, when the diode bridge circuit rectifies the output voltage of the AC power supply, the two diodes are always turned on. For this reason, when the input side transistor and the output side short circuit transistor are turned on, four ON voltages are generated as losses.

  On the other hand, in the first aspect of the invention, as described above, three elements among the first to fifth switching elements and the current limiting element are energized. For this reason, the ON voltage is generated as a loss in the three elements. Therefore, in the power conversion device that converts AC power into DC power, it is possible to reduce the loss that occurs as the ON voltage. For this reason, the efficiency of power conversion can be improved.

In invention of Claim 2, 1st voltage detection means (51) which detects the voltage between the positive electrode of an alternating current power supply, and a negative electrode,
When the detection voltage of the first voltage detection means is a negative voltage, the charge control means (S133) turns on the first and third switching elements (Q1p, Q3p) to turn on the second and fifth switching elements. The element (Q2p, Q5p) is turned off and the fourth switching element (Q4p) is repeatedly turned on / off,
When the detection voltage of the first voltage detection means is a positive voltage, the charge control means (S131) turns on the second and fourth switching elements (Q2p, Q4p), and the third and fifth switching elements The element (Q3p, Q5p) is turned off to repeatedly turn on / off the first switching element (Q1p).

The invention according to claim 3 includes second voltage detection means (52) for detecting a voltage between the positive electrode and the negative electrode of the DC load,
The charge control means controls the first to fifth switching elements based on the detection voltages of the first and second voltage detection means, whereby a current (from the AC power supply (2) to the bridge circuit (20) ( Iac) is characterized in that the change in the current value with respect to the time axis is sinusoidal, and the phase difference between the output voltage and current of the AC power supply is brought close to zero.

According to the third aspect of the invention, the power factor of the AC power output from the AC power supply can be made close to 1, so that power conversion from AC power to DC power can be performed efficiently.

In the invention according to claim 4, a bridge circuit which is arranged between the AC power source (2) and the DC load (3) and is constituted by the first to fourth switching elements (Q1p, Q2p, Q3p, Q4p). (20) and
A reactor (30) disposed between the bridge circuit and the positive electrode of the DC load;
A current limiting element (D1) that is disposed between the reactor and the positive electrode of the DC load and restricts current from flowing from the positive electrode side of the DC load to the reactor side;
A fifth switching element (Q5) disposed between the common connection terminal between the reactor and the current limiting element and the negative electrode of the DC load;
Charge control means (S150, S151) for controlling the first to fifth switching elements,
The first switching element (Q1p) is disposed between the positive electrode of the AC power source and the reactor,
The second switching element (Q2p) is disposed between the negative electrode of the AC power supply and the negative electrode of the DC load,
The third switching element (Q3p) is disposed between the positive electrode of the AC power source and the negative electrode of the DC load,
The fourth switching element (Q4p) is disposed between the negative electrode of the AC power supply and the reactor,
The charge control means (S150, S151) turns on the second and fourth switching elements (Q2p, Q4p) and turns off one of the first and third switching elements (Q1p, Q3p). The other switching element is repeatedly turned on / off in synchronization with the fifth switching element,
When the second and fourth switching elements are turned on, the third switching element is turned off and the first and fifth switching elements are turned on, the first, second, and fifth electrodes between the electrodes of the AC power supply are turned on. Current is passed through the switching element and the reactor to store energy in the reactor,
When the second and fourth switching elements are turned on and the first, third and fifth switching elements are turned off, the second and fourth switching elements and the current limit are based on the energy stored in the reactor. Current flows through the element and DC load,
When the second and fourth switching elements are turned on, the first switching element is turned off and the third switching element and the fifth switching element are turned on, the third, fourth, The fifth switching element and the reactor are configured to store an energy by flowing an electric current through the reactor.
In invention of Claim 5, 1st voltage detection means (51) which detects the voltage between the positive electrode of an alternating current power supply and a negative electrode is provided,
When the detection voltage of the first voltage detection means is a positive voltage, the charge control means (S150) turns on the second and fourth switching elements (Q2p, Q4p) and turns on the third switching element (Q3p). And the first switching element (Q1p) and the fifth switching element (Q5p) are repeatedly turned on / off in synchronization with each other,
When the detection voltage of the first voltage detection means is a negative voltage, the charge control means (S151) turns on the second and fourth switching elements (Q2p, Q4p), and the first switching element (Q1p) And the third switching element (Q3p) and the fifth switching element (Q5p) are repeatedly turned on / off in synchronization with each other.
In the invention according to claim 6, a bridge circuit which is arranged between the AC power source (2) and the DC load (3) and is constituted by the first to fourth switching elements (Q1p, Q2p, Q3p, Q4p). (20) and
A reactor (30) disposed between the bridge circuit and the positive electrode of the DC load;
A current limiting element (D1) that is disposed between the reactor and the positive electrode of the DC load and restricts current from flowing from the positive electrode side of the DC load to the reactor side;
A fifth switching element (Q5) disposed between the common connection terminal between the reactor and the current limiting element and the negative electrode of the DC load;
Charge control means (S150, S151) for controlling the first to fifth switching elements,
The first switching element (Q1p) is disposed between the positive electrode of the AC power source and the reactor,
The second switching element (Q2p) is disposed between the negative electrode of the AC power supply and the negative electrode of the DC load,
The third switching element (Q3p) is disposed between the positive electrode of the AC power source and the negative electrode of the DC load,
The fourth switching element (Q4p) is disposed between the negative electrode of the AC power supply and the reactor,
In the first charge control period, the charge control means (S150) turns on the second and fourth switching elements, turns off the third switching element, and repeatedly turns on and off the first and fifth switching elements. It is what
When the second and fourth switching elements are turned on, the third switching element is turned off and the first and fifth switching elements are turned on, the first, second, and fifth electrodes between the electrodes of the AC power supply are turned on. Current is passed through the switching element and the reactor to store energy in the reactor,
When the second and fourth switching elements are turned on and the first, third and fifth switching elements are turned off, the second and fourth switching elements and the current limit are based on the energy stored in the reactor. Current flows through the element and DC load,
When the second, fourth, and fifth switching elements are turned on and the first and third switching elements are turned off, the second, fourth, and fifth switching elements are based on the energy stored in the reactor. Current through
In the second charge control period, the charge control means (S151) turns on the second and fourth switching elements and turns off the first switching element.
The third and fifth switching elements repeatedly turn on and off the third and fifth switching elements,
When the second and fourth switching elements are turned on, the first switching element is turned off and the third and fifth switching elements are turned on, the third, fourth, and fifth electrodes between the electrodes of the AC power supply are turned on. Current is passed through the switching element and the reactor to store energy in the reactor,
When the second and fourth switching elements are turned on and the first, third and fifth switching elements are turned off, the second and fourth switching elements and the current limit are based on the energy stored in the reactor. Current flows through the element and DC load,
When the second, fourth, and fifth switching elements are turned on and the first and third switching elements are turned off, the second, fourth, and fifth switching elements are based on the energy stored in the reactor. It is characterized in that a current is passed through.

The invention according to claim 7 includes first voltage detecting means (51) for detecting a voltage between the positive electrode and the negative electrode of the AC power source,
When the detection voltage of the first voltage detection means is a positive voltage, the charge control means (S150) turns on the second and fourth switching elements and turns off the third switching element to turn the first and second 5 The switching element is repeatedly turned on and off,
When the detection voltage of the first voltage detection means is a negative voltage, the charge control means (S151) turns on the second and fourth switching elements, turns off the first switching element, and turns on the third, 5 switching elements are repeatedly turned on and off.
The invention according to claim 8 includes first voltage detection means (51) for detecting a voltage between the positive electrode and the negative electrode of the AC power source,
When the detection voltage of the first voltage detection means is a positive voltage, the charge control means (S150) turns on the second and fourth switching elements and turns off the third switching element to turn the first and second 5 The switching element is repeatedly turned on and off,
When the detection voltage of the first voltage detection means is a negative voltage, the charge control means (S151) turns on the second and fourth switching elements, turns off the first switching element, and turns on the third, 5 switching elements are repeatedly turned on and off .
In the invention according to claim 8, the bridge circuit which is arranged between the AC power source (2) and the DC load (3) and is constituted by the first to fourth switching elements (Q1p, Q2p, Q3p, Q4p). (20) and
A reactor (30) disposed between the bridge circuit and the positive electrode of the DC load;
A current limiting element (D1) that is disposed between the reactor and the positive electrode of the DC load and restricts current from flowing from the positive electrode side of the DC load to the reactor side;
A fifth switching element (Q5) disposed between the common connection terminal between the reactor and the current limiting element and the negative electrode of the DC load ;
Charge control means (S130, S131, S132, S133, S150, S151) for controlling the first to fifth switching elements,
The first switching element (Q1p) is disposed between the positive electrode of the AC power source and the reactor,
The second switching element (Q2p) is disposed between the negative electrode of the AC power supply and the negative electrode of the DC load,
The third switching element (Q3p) is disposed between the positive electrode of the AC power source and the negative electrode of the DC load,
The fourth switching element (Q4p) is disposed between the negative electrode of the AC power supply and the reactor,
The charge control means (S150) turns on the second and fourth switching elements (Q2p, Q4p) and turns off the third switching element (Q3p) during the first charge control time, and turns off the first and fifth switching elements (Q3p). The switching elements (Q1p, Q5p) are repeatedly turned on and off,
When the second and fourth switching elements are turned on and the third switching element is turned off and the first and fifth switching elements are turned on, the first, second, and fifth electrodes between the electrodes of the AC power supply are turned on. Current is passed through the switching element and the reactor to store energy in the reactor,
When the second and fourth switching elements are turned on and the third switching element is turned off and the first and fifth switching elements are turned off, the second and fourth switching elements are based on the energy stored in the reactor. Current flows through the element, current limiting element, and DC load,
The charge control means (S151) turns on the first and third switching elements (Q1p, Q3p) and turns off the second switching element (Q2p) during the second charge control time, and turns on the fourth and fifth The switching elements (Q4p, Q5p) are repeatedly turned on and off,
When the first and third switching elements are turned on, the second switching element is turned off, and the fourth and fifth switching elements are turned on, the reactor, and the third, fourth, , Passing current through the fifth switching element to store energy in the reactor,
When the first and third switching elements are turned on and the second, fourth and fifth switching elements are turned off, the first and third switching elements and the current limiting element are based on the energy stored in the reactor. And a current is allowed to flow through a DC load .

The invention according to claim 9 includes first voltage detecting means (51) for detecting a voltage between the positive electrode and the negative electrode of the AC power source,
  When the detection voltage of the first voltage detection means is a positive voltage, the charge control means (S150) turns on the second and fourth switching elements (Q2p, Q4p) and turns on the third switching element (Q3p). It is turned off and the first and fifth switching elements (Q1p, Q5p) are repeatedly turned on / off,
  When the detection voltage of the first voltage detection means is a negative voltage, the charge control means (S151) turns on the first and third switching elements (Q1p, Q3p) and turns on the second switching element (Q2p). The fourth and fifth switching elements (Q4p, Q5p) are repeatedly turned on and off to turn off and on.

The invention according to claim 10 includes second voltage detection means (52) for detecting a voltage between the positive electrode and the negative electrode of the DC load,
The charge control means controls the first to fifth switching elements based on the detection voltages of the first and second voltage detection means, whereby a current (from the AC power supply (2) to the bridge circuit (20) ( Iac) is characterized in that the change in the current value with respect to the time axis is sinusoidal, and the phase difference between the output voltage and current of the AC power supply is brought close to zero.

According to the invention described in claim 10 , since the power factor of the AC power output from the AC power source can be made close to 1, power conversion from AC power to DC power can be performed efficiently.

In invention of Claim 11 , the power converter device (1) as described in any one of Claim 1 thru | or 10 ,
And seventh and eighth switching elements (Q7, Q8) connected in series between the positive electrode and the negative electrode of the DC load (3) of the power converter,
Of the seventh and eighth switching elements (Q7, Q8), the seventh switching element (Q7) on the positive electrode side of the DC load constitutes a current limiting element,
Of the seventh and eighth switching elements (Q7, Q8), the eighth switching element (Q8) on the negative electrode side of the DC load constitutes the fifth switching element (Q5),
The common connection terminal (T1) between the seventh and eighth switching elements and the first electrode (110a) of the stator coil (110) constituting the three-phase AC motor are connected,
A first switch (SW1) for connecting or opening between the bridge circuit of the power converter and the AC power source (2);
A second switch that connects or opens the common connection element (T2) between the second and fourth switching elements (Q2p, Q4p) of the power converter and the second electrode (110b) of the stator coil ( SW2)
A third switch for connecting or opening between the common connection element (T3) between the first and third switching elements (Q1p, Q3p) of the power converter and the third electrode (110c) of the stator coil (SW3),
A fourth switch (SW4) disposed between the common connection element (T4) between the first and fourth switching elements and the positive electrode of the DC load;
A fifth switch (SW5) disposed between the common connection element (T4) between the first and fourth switching elements and the reactor;
Switch control means (50) for controlling the first to fifth switches;
When the switch control means turns on the second, third, and fourth switches among the first to fifth switches, the first, second, third, fourth, seventh, and eighth switching elements are turned on. The common connection terminal (T3) between the first and third switching elements, the common connection terminal (T2) between the second and fourth switching elements, and the seventh and eighth switching elements. Inverter control means (50) for driving a three-phase AC motor by flowing an AC current from the common connection terminal (T1) to the stator coil,
When the switch control means turns on the first and fifth switches among the first to fifth switches, the charge control means controls the first to fourth switching elements and the seventh and eighth switching elements . It is characterized by that.

According to the eleventh aspect of the present invention, as in the first aspect, the loss generated as the ON voltage can be reduced when converting AC power to DC power. Can be improved.

In the invention described in claim 12, a bridge circuit which is arranged between the DC power supply (4) and the AC load (5) and is constituted by the first to fourth switching elements (Q1n, Q2n, Q3n, Q4n). (20B)
A reactor (30) disposed between the bridge circuit and the positive electrode of the DC power supply;
A sixth switching element (Q6) disposed between the reactor and the positive electrode of the DC power supply;
Arranged between the common connection terminal between the reactor and the sixth switching element (Q6) and the negative electrode of the DC power supply (4), current flows from the common connection terminal side to the negative electrode side of the DC power supply (4). A current limiting element (D2) that prevents current flow;
Reverse flow control means (131a, 133a) for controlling the first to fourth switching elements and the sixth switching element,
The first switching element (Q1n) is disposed between the positive electrode of the AC load and the reactor,
The second switching element (Q2n) is disposed between the negative electrode of the AC load and the negative electrode of the DC power source,
The third switching element (Q3n) is disposed between the positive electrode of the AC load and the negative electrode of the DC power source,
The fourth switching element (Q4n) is disposed between the negative electrode of the AC load and the reactor,
The reverse flow control means (S 131a ) turns on the first, second, and sixth switching elements (Q1n, Q2n, Q6n) and turns on the third switching element (Q3n) in the first reverse flow control period. Turning off and repeatedly turning on and off the fourth switching element (Q4n),
When the first, second, fourth, and sixth switching elements are turned on and the third switching element is turned off, current flows through the second, fourth, and sixth switching elements and the reactor between the electrodes of the DC power supply. To store energy in the reactor,
When the first, second and sixth switching elements are turned on and the third and fourth switching elements are turned off, the first and second switching elements and the AC load are based on the energy stored in the reactor. Current through
The reverse flow control means ( 133a ) turns on the third, fourth and sixth switching elements (Q3n, Q4n, Q6n) and turns off the second switching element (Q2n) in the second reverse flow control period. The first switching element (Q1n) is repeatedly turned on and off,
When the first, third, fourth, and sixth switching elements are turned on and the second switching element is turned off, current flows through the first, third, and sixth switching elements and the reactor between the electrodes of the DC power supply. To store energy in the reactor,
Based on the energy stored in the reactor when the third, fourth, and sixth switching elements are turned on and the first and second switching elements are turned off, the third, fourth, and sixth switching elements , A current limiting element, and a current flowing through an AC load .

According to the twelfth aspect of the present invention, when a current is passed through the reactor between the two electrodes of the DC power source and the current is passed through the AC load based on the energy stored in the reactor, Three elements among the switching element, the sixth switching element, and the current limiting element are energized. For this reason, the ON voltage is generated as a loss in the three elements. Therefore, in the power conversion device that converts DC power into AC power, it is possible to reduce loss that occurs as an ON voltage. For this reason, the efficiency of power conversion can be improved.

In invention of Claim 13 , 1st voltage detection means (51) which detects the output voltage of AC load,
When the detection voltage of the first voltage detection means is a positive voltage, the reverse power flow control means (S 131a ) turns on the first, second, and sixth switching elements (Q1n, Q2n, Q6n), The third switching element (Q3n) is turned off and the fourth switching element (Q4n) is repeatedly turned on / off.
When the detection voltage of the first voltage detection means is a negative voltage, the reverse power flow control means ( 133a ) turns on the third, fourth, and sixth switching elements (Q3n, Q4n, Q6n) and Repeat der Rukoto which turns on and off the first switching element and turning off the second switching element (Q2n) (Q1n), characterized.

In a fourteenth aspect of the present invention, a bridge circuit that is arranged between the DC power source (4) and the AC load (5) and includes the first to fourth switching elements (Q1n, Q2n, Q3n, Q4n). (20B)
A reactor (30) disposed between the bridge circuit and the positive electrode of the DC power supply;
A sixth switching element (Q6) disposed between the reactor and the positive electrode of the DC power supply;
Arranged between the common connection terminal between the reactor and the sixth switching element (Q6) and the negative electrode of the DC power supply (4), current flows from the common connection terminal side to the negative electrode side of the DC power supply (4). A current limiting element (D2) that prevents current flow;
Reverse flow control means (150b, 151b) for controlling the first to fourth switching elements and the sixth switching element,
The first switching element (Q1n) is disposed between the positive electrode of the AC load and the reactor,
The second switching element (Q2n) is disposed between the negative electrode of the AC load and the negative electrode of the DC power source,
The third switching element (Q3n) is disposed between the positive electrode of the AC load and the negative electrode of the DC power source,
The fourth switching element (Q4n) is disposed between the negative electrode of the AC load and the reactor,
The reverse flow control means (S150b) turns on the first and second switching elements (Q1n, Q2n) and turns off the third switching element (Q3n) in the first reverse flow control period. The sixth switching element (Q4n, Q6n) is repeatedly turned on / off,
When the first, second, fourth, and sixth switching elements are turned on and the third switching element is turned off, current flows through the second, fourth, and sixth switching elements and the reactor between the electrodes of the DC power supply. To store energy in the reactor,
When the first and second switching elements are turned on and the third, fourth, and sixth switching elements are turned off, the first and second switching elements and the current limiting element are based on the energy stored in the reactor. Current through an AC load, and
The reverse flow control means (S151b) turns on the third and fourth switching elements (Q3n, Q4n) and turns off the first switching element (Q1n) in the second reverse flow control period. The sixth switching element (Q4n, Q6n) is repeatedly turned on / off,
When the second, third, fourth, and sixth switching elements are turned on and the first switching element is turned off, current flows through the second, fourth, and sixth switching elements and the reactor between the electrodes of the DC power supply. To store energy in the reactor,
Based on the energy stored in the reactor when the third and fourth switching elements are turned on and the first, second and sixth switching elements are turned off, the third and fourth switching elements and current A current is allowed to flow through the limiting element and the AC load .

The invention according to claim 15 comprises first voltage detection means (51) for detecting the output voltage of the AC load,
When the detection voltage of the first voltage detection means is a positive voltage, the reverse power flow control means (S150b) turns on the first and second switching elements (Q1n, Q2n) and turns on the third switching element (Q3n). ) To turn on / off the fourth and sixth switching elements (Q4n, Q6n) repeatedly,
When the detection voltage of the first voltage detection means is a negative voltage, the reverse power flow control means (S151b) turns on the third and fourth switching elements (Q3n, Q4n) and turns on the first switching element (Q1n). ) the second off the sixth switching element (Q4n, characterized der Rukoto one which repeatedly turned on and off Q6n).

In invention of Claim 16, it has the 2nd voltage detection means (52) which detects the output voltage of DC power supply,
The reverse power flow control means controls the first to fourth and sixth switching elements based on the detection voltages of the first and second voltage detection means, thereby causing the AC load (5) from the bridge circuit (20). The change in the current value with respect to the time axis of the current (Iac) flowing in the sine is made sinusoidal, and the phase difference between the voltage and current between the electrodes of the AC load is made close to zero.

In invention of Claim 17, the power converter device (1) as described in any one of Claim 12 thru | or 17,
Seventh and eighth switching elements (Q7, Q8) connected in series between the positive electrode and the negative electrode of the DC power source (3) of the power converter,
Of the seventh and eighth switching elements (Q7, Q8), the eighth switching element (Q8) on the negative electrode side of the DC power supply constitutes a current limiting element,
Of the seventh and eighth switching elements (Q7, Q8), the seventh switching element (Q7) on the positive electrode side of the DC power supply constitutes the sixth switching element (Q6),
The common connection terminal (T1) between the seventh and eighth switching elements and the first electrode (110a) of the stator coil (110) constituting the three-phase AC motor are connected,
A first switch (SW1) for connecting or opening the bridge circuit of the power converter and the AC load (5);
A second switch that connects or opens between the common connection element (T2) between the second and fourth switching elements (Q2n, Q4n) of the power converter and the second electrode (110b) of the stator coil ( SW2)
A third switch that connects or opens between the common connection element (T3) between the first and third switching elements (Q1n, Q3n) of the power converter and the third electrode (110c) of the stator coil. (SW3),
A fourth switch (SW4) disposed between the common connection element (T4) between the first and fourth switching elements and the positive electrode of the DC load;
A fifth switch (SW5) disposed between the common connection element (T4) between the first and fourth switching elements and the reactor;
Switch control means (50) for controlling the first to fifth switches;
When the switch control means turns on the second, third, and fourth switches among the first to fifth switches, the first, second, third, fourth, seventh, and eighth switching elements are turned on. The common connection terminal (T3) between the first and third switching elements, the common connection terminal (T2) between the second and fourth switching elements, and the seventh and eighth switching elements. And an inverter control means (50) for driving a three-phase AC motor by flowing an AC current from a common connection terminal (T1) between the stator coil,
The reverse power flow control means controls the first to fourth and seventh switching elements when the switch control means turns on the first and fifth switches among the first to fifth switches. .

  In addition, the code | symbol in the bracket | parenthesis of each means described in this column and the claim shows the correspondence with the specific means as described in embodiment mentioned later.

It is a figure which shows the electric circuit structure of the power converter device in 1st Embodiment of this invention. It is a flowchart which shows charge control of the control apparatus of FIG. It is a figure which shows the magnitude relationship of the absolute value of the output voltage of AC power supply in 1st Embodiment, and the voltage between both electrodes of DC load, and the ON / OFF timing of each switching element. It is a figure which shows the flow of the electric current in 1st Embodiment. It is a figure which shows the flow of the electric current in 1st Embodiment. It is a figure which shows the flow of the electric current in 1st Embodiment. It is a figure which shows the flow of the electric current in 1st Embodiment. It is a flowchart which shows charge control of the control apparatus of the modification of 1st Embodiment. It is a flowchart which shows charge control of the control apparatus of 2nd Embodiment of this invention. It is a figure which shows the magnitude relationship of the absolute value of the output voltage of AC power supply in 2nd Embodiment, and the voltage between both electrodes of DC load, and the ON / OFF timing of each switching element. It is a figure which shows the flow of the electric current in 2nd Embodiment. It is a figure which shows the flow of the electric current in 2nd Embodiment. It is a figure which shows the magnitude relationship of the absolute value of the output voltage of AC power supply and the voltage between both electrodes of DC load in 3rd Embodiment of this invention, and the ON / OFF timing of each switching element. It is a figure which shows the flow of the electric current in 3rd Embodiment. It is a figure which shows the flow of the electric current in 3rd Embodiment. It is a figure which shows the electric circuit structure of the power converter device in 4th Embodiment of this invention. It is a flowchart which shows charge control of the control apparatus of FIG. It is a figure which shows the magnitude relationship of the absolute value of the output voltage of AC power supply in 4th Embodiment, and the voltage between both electrodes of DC load, and the ON / OFF timing of each switching element. It is a figure which shows the flow of the electric current in 4th Embodiment. It is a figure which shows the flow of the electric current in 4th Embodiment. It is a figure which shows the electric circuit structure of the power converter device in 5th Embodiment of this invention. It is a flowchart which shows charge control of the control apparatus of FIG. It is a figure which shows the magnitude relationship of the absolute value of the voltage between both electrodes of the alternating current load in 5th Embodiment, and the output voltage of a battery, and the ON / OFF timing of each switching element. It is a figure which shows the flow of the electric current in 5th Embodiment. It is a figure which shows the flow of the electric current in 5th Embodiment. It is a figure which shows the flow of the electric current in 5th Embodiment. It is a figure which shows the flow of the electric current in 5th Embodiment. It is a flowchart which shows the reverse power flow control of the control apparatus in 6th Embodiment of this invention. It is a figure which shows the magnitude relationship of the absolute value of the voltage between both electrodes of the alternating current load in 6th Embodiment, and the output voltage of a battery, and the ON / OFF timing of each switching element. It is a figure which shows the flow of the electric current in 6th Embodiment. It is a figure which shows the flow of the electric current in 6th Embodiment. It is a figure which shows the electric circuit structure of the power converter device in 7th Embodiment of this invention. It is a flowchart which shows the reverse power flow control of the control apparatus in 7th Embodiment. It is a figure which shows the magnitude relationship of the absolute value of the voltage between both electrodes of the alternating current load in 7th Embodiment, and the output voltage of a battery, and the ON / OFF timing of each switching element. It is a figure which shows the flow of the electric current in 7th Embodiment. It is a figure which shows the flow of the electric current in 7th Embodiment. It is a circuit block diagram of the control apparatus for three-phase alternating current motors of 8th Embodiment of this invention. It is a graph which shows the ON / OFF timing of the relay of 8th Embodiment. It is a circuit block diagram of the control apparatus for three-phase alternating current motors of 9th Embodiment of this invention. It is a graph which shows the ON / OFF timing of the relay of 9th Embodiment. It is a circuit block diagram of the control apparatus for three-phase alternating current motors of 10th Embodiment of this invention. It is a figure which shows the circuit structure of the power converter device for demonstrating the subject of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other are given the same reference numerals in the drawings in order to simplify the description.

(First embodiment)
FIG. 1 shows a first embodiment of a power conversion device of the present invention. FIG. 1 shows an electric circuit configuration of the power conversion device 1 of the present embodiment.

  As shown in FIG. 1, the power conversion device 1 includes a low-pass filter 10, a bridge circuit 20, a reactor 30, a switching element Q5, diodes D1 and D2, a smoothing capacitor 40, a control device 50, voltage sensors 51 and 52, and a current sensor. 53.

  The low-pass filter 10 is disposed between the positive electrode and the negative electrode of the AC power supply 2. The bridge circuit 20 is disposed between the AC power supply 2 and the DC load 3. The bridge circuit 20 includes switching elements Q1p to Q4p. Switching element Q1p is arranged between the positive electrode of AC power supply 2 and the positive electrode of DC load 3. Switching element Q2p is arranged between the negative electrode of AC power supply 2 and the negative electrode of DC load 3. Switching element Q3p is arranged between the positive electrode of AC power supply 2 and the negative electrode of DC load 3. Switching element Q4p is arranged between the negative electrode of AC power supply 2 and the positive electrode of DC load 3. A battery is used as the DC load 3 of the present embodiment.

  Reactor 30 is arranged between the common connection terminal between switching elements Q1p and Q4p and the positive electrode of DC load 3. The diode D1 is disposed between the reactor 30 and the positive electrode of the DC load 3. The diode D1 prevents current from flowing from the positive electrode side of the DC load 3 to the reactor 30 side.

  Switching element Q <b> 5 is arranged between the common connection element between reactor 30 and diode D <b> 1 and the negative electrode of DC load 3. As the switching elements Q1p, Q2p, Q3p, Q4p, and Q5 of this embodiment, for example, insulated gate bipolar transistors are used. As the switching elements Q1p, Q2p, Q3p, and Q4p, elements that can endure even when a high reverse voltage is applied between the collector terminal and the emitter terminal are used.

  The diode D5 is disposed in antiparallel with the switching element Q5 between the plus electrode and the minus electrode of the DC load 3. Diode D2 prevents current from flowing from the common connection element side between reactor 30 and diode D1 to the negative electrode side of DC load 3.

  The smoothing capacitor 40 is disposed between the plus electrode and the minus electrode of the DC load 3. The smoothing capacitor 40 smoothes the voltage between both electrodes of the DC load 3.

  The control device 50 includes a microcomputer, a memory, and the like, and performs a charging process for converting the AC power of the AC power source 2 into DC power and applying it to the DC load (battery) 3. When performing the charging process, the control device 50 performs switching control of the switching elements Q1p, Q2p, Q3p, Q4p, and Q5 based on the required power from the electronic control device 60 and the output signals of the sensors 51, 52, and 53. To do.

  The voltage sensor 51 detects the voltage between the positive electrode and the negative electrode of the AC power supply 2. The voltage sensor 52 detects a voltage between the plus electrode and the minus electrode of the DC load 3. The current sensor 53 detects a current flowing between the common connection terminal between the switching elements Q1p and Q4p and the reactor 30.

  Next, the charging process of the control apparatus 50 of this embodiment is demonstrated.

  First, when the control device 50 is provided with the required power P ′ from the electronic control device 60, the execution of the charging process is started. The required power P ′ is a power value requested from the electronic control unit 60 to be supplied from the AC power source 2 to the DC load 3.

  The controller 50 divides the required power P ′ by the detection voltage Vac of the voltage sensor 51 to obtain the required current Iac ′ (= P ′ / Vac). The requested current Iac ′ is a requested value requested from the electronic control unit 60 so as to be output from the AC power supply 2. The control device 50 controls the switching elements Q1p,... Q4p, Q5 so that the actual current Iac output from the AC power source 2 through the low-pass filter 10 to the bridge circuit 20 approaches the required current Iac '.

  Details of the charging process will be described below with reference to FIGS. FIG. 2 is a flowchart showing the charging process. 3A is a timing chart showing the relationship between the absolute value | Vac | of the output voltage of the AC power supply 2 and the voltage VB between both electrodes of the DC load 3, and FIGS. 3B to 3F show the switching element Q1p. , Q2p, Q3p, Q4p, Q5 is a timing chart showing on and off timings. 4 to 7 are circuit diagrams illustrating the flow of current in the power conversion device 1.

  First, in step S100 of FIG. 2, it is determined whether or not the detection voltage (that is, the output voltage of the AC power supply 2) Vac of the voltage sensor 51 is greater than or equal to zero. When the determination is YES because the detection voltage Vac of the voltage sensor 51 is greater than or equal to zero, in the next step S110, the absolute value | Vac | of the detection voltage of the voltage sensor 51 is the detection voltage of the voltage sensor 52 (ie, the DC load 3 It is determined whether the voltage between the two electrodes is smaller than VB.

  Here, when it is determined that the absolute value | Vac | of the detection voltage of the voltage sensor 51 is smaller than the detection voltage VB of the voltage sensor 52 and YES is determined in step S110, the process proceeds to step S130 and boost control is performed.

  Specifically, switching elements Q1p, Q2p, Q4p are turned on, switching element Q3p is turned off, and switching control (PWM control) is performed on switching element Q5.

  When performing this switching control, the ON period during which the switching element Q5 is turned on and the OFF period during which the switching element Q5 is turned off are set so that the actual current Iac approaches the required current Iac '.

  First, when the switching element Q5 is turned on, as indicated by the arrow of Mode 1 in FIG. 4, the current from the positive electrode of the AC power supply 2 is changed to the low pass filter 10, the switching element Q1p, the reactor 30, the switching elements Q5, Q2p, and the low pass. It flows through the filter 10 to the negative electrode of the AC power supply 2. At this time, energy is stored in the reactor 30.

  Further, when the switching element Q5 is turned off, the low-pass filter 10, the switching element Q1p, the current sensor 53, the positive electrode of the AC power source 2, based on the energy stored in the reactor 30, as indicated by the arrow of Mode 2 in FIG. It flows to the positive electrode of the AC power supply 2 through the reactor 30, the DC load 3, the switching element Q2p, and the low-pass filter 10.

  Here, the duty ratio {= (ON period) / (ON period + OFF period)} of the switching element Q1p is 1, and the duty ratio of the switching element Q5p is {1- (| Vac | / VB)}. Therefore, the duty ratio of switching element Q5p decreases as | Vac | increases, and the duty ratio of switching element Q5p increases as | Vac | decreases. For this reason, the change of the current value with respect to the time axis in the actual current Iac is made sinusoidal, and the power factor is set to 1 by bringing the phase difference between the output voltage of the AC power supply 2 and the actual current Iac close to zero. It will be closer. Therefore, the switching element Q5 operates as a boost PFC circuit.

  Further, in step S100 described above, when it is determined NO because the detection voltage Vac of the voltage sensor 51 is less than zero, the absolute value | Vac | of the detection voltage of the voltage sensor 51 is equal to the voltage sensor 52 in the next step S120. It is determined whether or not it is smaller than the detection voltage VB.

  Here, assuming that the absolute value | Vac | of the detection voltage of the voltage sensor 51 is smaller than the detection voltage VB of the voltage sensor 52 (| Vac | <VB), if YES is determined in step S120, the process proceeds to step S132. Perform boost control.

  Specifically, the switching elements Q1p, Q3p, Q4p are turned on, the switching element Q2p is turned off, and switching control (PWM control) is performed on the switching element Q5. When performing this switching control, the ON period and the OFF period of the switching element Q5 are set so that the actual current Iac approaches the required current Iac '.

  First, when the switching element Q5 is turned on, the current from the negative electrode of the AC power supply 2 is changed to the low pass filter 10, the switching element Q4p, the current sensor 53, the reactor 30, the switching element Q5, as indicated by the arrow of Mode 5 in FIG. It flows to the positive electrode of the AC power supply 2 through Q3p and the low-pass filter 10. At this time, energy is stored in the reactor 30.

  Further, when the switching element Q5 is turned off, the low-pass filter 10, the switching element Q4p, the current sensor 53, the negative electrode of the AC power supply 2, based on the energy stored in the reactor 30, as indicated by the arrow of Mode 6 in FIG. It flows to the negative electrode of the AC power supply 2 through the reactor 30, the diode D1, the DC load 3, the switching element Q3p, and the low-pass filter 10.

  Here, the duty ratio {= (ON period) / (ON period + OFF period)} of the switching element Q4p is 1, and the duty ratio of the switching element Q5p is {1- (| Vac | / VB)}. Therefore, the duty ratio of switching element Q5p decreases as | Vac | increases, and the duty ratio of switching element Q5p increases as | Vac | decreases. For this reason, the change of the current value with respect to the time axis in the actual current Iac is made sinusoidal, and the power factor is set to 1 by bringing the phase difference between the output voltage of the AC power supply 2 and the actual current Iac close to zero. It will be closer. Therefore, the switching element Q5 operates as a boost PFC circuit.

  In step S110, assuming that the absolute value | Vac | of the detection voltage of the voltage sensor 51 is equal to or higher than the detection voltage VB of the voltage sensor 52 (| Vac | ≧ VB), if NO, the process proceeds to step S131. Implement step-down control.

  Specifically, switching elements Q2p and Q4p are turned on, switching elements Q3p and Q5 are turned off, and switching control (PWM control) is performed on switching element Q1p. When performing this switching control, the ON period and OFF period of the switching element Q1p are set so that the actual current Iac approaches the required current Iac '.

  First, when the switching element Q1p is turned on, as indicated by the arrow of Mode 4 in FIG. 6, the current from the positive electrode of the AC power supply 2 is changed to the low-pass filter 10, the switching element Q1p, the current sensor 53, the reactor 30, the diode D1, and the DC. It flows to the negative electrode of the AC power supply 2 through the load 40, the switching element Q2p, and the low-pass filter 10. At this time, energy is stored in the reactor 30 and the DC load 40, respectively.

  When switching element Q1p is turned off, switching element Q4p, current sensor 53, reactor 30, diode D1, and switching element Q2, based on the energy stored in reactor 30, as indicated by the arrow of Mode 3 in FIG. Current flows through Q4p.

  Here, (VB / | Vac |) is used as the duty ratio {= (ON period) / (ON period + OFF period)} of the switching element Q1p. Therefore, as | Vac | increases, the duty ratio of switching element Q1p decreases, and as | Vac | decreases, the duty ratio of switching element Q1p increases. Therefore, the change of the current value with respect to the time axis in the actual current Iac is made close to a sine wave, and the phase difference between the output voltage of the AC power supply 2 and the actual current Iac is made close to zero.

  When the step-down control is performed, the switching element Q1p operates as a switching element of the step-down chopper circuit, and the switching element Q4p operates as a rectifier diode (freewheeling diode).

  In step S120 described above, if the absolute value | Vac | of the voltage sensor 51 is greater than the detection voltage VB of the voltage sensor 51 (| Vac | ≧ VB), if NO, the process proceeds to step S133. Thus, step-down control is performed.

  Specifically, switching elements Q1p and Q3p are turned on, switching elements Q2p and Q5 are turned off, and switching control (PWM control) is performed on switching element Q4p. When this switching control is performed, the ON period and the OFF period of the switching element Q4p are set so that the actual current Iac approaches the required current Iac '.

  First, when the switching element Q4p is turned on, as indicated by the arrow of Mode 7 in FIG. 7, the current from the negative electrode of the AC power supply 2 is changed to the low-pass filter 10, the switching element Q4p, the current sensor 53, the reactor 30, the diode D1, and the DC. It flows to the positive electrode of the AC power supply 2 through the load 40, the switching element Q3p, and the low-pass filter 10. At this time, energy is stored in the reactor 30 and the DC load 40, respectively.

  When switching element Q4p is turned off, switching element Q1p, current sensor 53, reactor 30, diode D1, DC load 40, and the like, based on the energy stored in reactor 30, as indicated by the arrow of Mode 8 in FIG. A current flows through the switching element Q3p.

  Here, (VB / | Vac |) is used as the duty ratio {= (ON period) / (ON period + OFF period)} of the switching element Q4p. Therefore, as | Vac | increases, the duty ratio of switching element Q4p decreases, and as | Vac | decreases, the duty ratio of switching element Q4p increases. Therefore, the change of the current value with respect to the time axis in the actual current Iac is made close to a sine wave, and the phase difference between the output voltage of the AC power supply 2 and the actual current Iac is made close to zero.

  When the step-down control is performed, the switching element Q4p operates as a switching element of the step-down chopper circuit, and the switching element Q1p operates as a rectifier diode (freewheeling diode).

  Thus, in a period in which | Vac | is larger than detection voltage VB, when power supply voltage is positive, switching element Q1p serves as a switching element of the step-down chopper circuit, and switching element Q4p serves as a rectifier diode. When the power supply voltage is negative, the switching element Q4p serves as a switching element for the step-down chopper circuit, and the switching element Q1p serves as a rectifier diode.

  As described above, the process proceeds to any one of steps S130 to S133 to control the switching elements Q1p to Q4p and Q5 to convert the output power of the AC power source 2 into DC power, and this DC power is converted to the DC load 3 Will be stored.

  Thereafter, in step S140, it is determined whether an operation end request is received from the electronic control unit 60. When it is determined NO because the operation end request has not been received from the electronic control unit 60, the process returns to step S100.

  Then, after finishing the process of step S100, S110 or the process of step S100, S120 until it receives the operation | movement completion request | requirement from the electronic control apparatus 60, switching element Q1p-, Q4p, in one step of step S130-S133, Q5 will be controlled. Thereafter, in step S140, if it is determined YES because an operation end request is received from the electronic control unit 60, the charging process is stopped.

  According to the present embodiment described above, when the control device 50 performs the charge control, three elements among the switching elements Q1p, Q2p, Q3p, Q4p, Q5 and the diode D1 are energized. For this reason, when the control device 50 performs the charge control, the ON voltage is lost in the three elements.

  In the above-described power conversion device of Patent Document 1, the ON voltage is generated as a loss by four elements.

  On the other hand, according to the present embodiment, as described above, the ON voltage is lost by the three elements. Therefore, in the power converter 1 that converts the AC power of the AC power supply 2 into DC power, the number of elements that generate the ON voltage can be reduced. For this reason, the efficiency of the power conversion of the power converter 1 which converts alternating current power into direct current power can be improved.

  In the present embodiment, in steps S130 to S133, the switching elements Q1p, Q2p, Q3p, Q4p, and Q5 are controlled so that the change in the current value with respect to the time axis in the actual current Iac approaches a sine wave shape and the AC power supply 2 The phase difference between the output voltage and the actual current Iac is close to zero. Thereby, since the power factor of the alternating current power output from the alternating current power supply 2 can be brought close to 1, power conversion can be performed efficiently.

  In the first embodiment described above, the flowchart of FIG. 2 is used when performing the charge control, but the flowchart of FIG. 8 may be used instead.

  Specifically, the difference between FIG. 2 and FIG. 8 will be described. In step S130 in FIG. 2, the switching element Q4p is turned on, but in step S130 in FIG. 8, the switching element Q4p is turned off. ing. In step S132 in FIG. 2, the switching element Q1p is turned on, but in step S132 in FIG. 8, the switching element Q1p is turned off.

(Second Embodiment)
In the first embodiment, the example in which the boost control and the buck control are switched according to the magnitude relationship between the absolute value | Vac | of the output voltage of the AC power supply and the voltage VB between both electrodes of the DC load has been described. Instead, in the second embodiment, an example in which the step-up / step-down control is always performed will be described.

  The hardware configuration of the power conversion device 1 of the present embodiment is the same as the hardware configuration of the power conversion device 1 of the first embodiment described above. For this reason, the charge control of the present embodiment will be described below with reference to FIGS.

  FIG. 9 is a flowchart showing the charging control of this embodiment, and FIG. 10A is a timing chart showing the relationship between the absolute value | Vac | of the output voltage of the AC power supply 2 and the voltage VB between both electrodes of the DC load 3. FIGS. 3B to 3F are timing charts showing the on / off timings of the switching elements Q1p, Q2p, Q3p, Q4p, and Q5. 11 and 12 are circuit diagrams illustrating the flow of current in the power conversion device 1.

  First, in step S100 of FIG. 9, it is determined whether or not the detection voltage (that is, the output voltage of the AC power supply 2) Vac of the voltage sensor 51 is greater than or equal to zero. Assuming that the detection voltage Vac of the voltage sensor 51 is equal to or greater than zero (Vac ≧ 0) and determining YES, step-up / step-down control described later is performed in step S150.

  In step S100 described above, assuming that the detection voltage Vac of the voltage sensor 51 is less than zero (Vac <0) and NO is determined, step-up / step-down control described later is performed in step S151.

  As described above, when the step-up / step-down control is performed in step S150 or step S151, it is determined whether or not an operation end request is received from the electronic control unit 60 in the next step S140. When it is determined NO because the operation end request has not been received from the electronic control unit 60, the process returns to step S100.

  Thereafter, until the operation end request is received from the electronic control unit 60, the determination in step S100, the step-up / step-down control in step S150 or step S151, and the NO determination in step S140 are repeated. And if the operation | movement completion request | requirement is received from the electronic control apparatus 60, it will determine with YES by step S140, and charge control will be complete | finished.

Next, the step-up / step-down control in step S150 and the step-up / step-down control in step S151 will be described.
(Step S150)
First, the switching element Q3p is turned off, the switching elements Q2p and Q4p are turned on, and the switching elements Q1p and Q5 are switched in synchronization. That is, switching element Q1p is turned on and switching element Q5 is turned on at the same timing, and switching element Q1p is turned off and switching element Q5 is turned off at the same timing. When switching the switching elements Q1p and Q5, the ON period and the OFF period of the switching elements Q1p and Q5 are set so that the actual current Iac approaches the required current Iac ′.

  First, when the switching elements Q1p and Q5 are turned on, the current from the positive electrode of the AC power supply 2 is changed to the low-pass filter 10, the switching element Q1p, the current sensor 53, the reactor 30, and the switching element as indicated by the arrow of Mode 1 in FIG. It flows to the negative electrode of AC power supply 2 through Q5, Q2p, and low-pass filter 10. At this time, energy is stored in the reactor 30.

  Further, when the switching elements Q1p and Q5 are turned off, as shown by the arrows of Mode 2 in FIG. 11, the current is changed to the reactor 30, the diode D1, the DC load 3, the switching elements Q2p, Q4p based on the energy stored in the reactor 30. And flows through the current sensor 30.

Such switching elements Q1p and Q5 are turned on and switching elements Q3p and Q5 are turned off repeatedly. At this time, (VB / (| Vac | + VB)) is used as the duty ratio of the switching elements Q1p and Q5. For this reason, the duty ratio of switching elements Q1p and Q5 decreases as | Vac | increases, and the duty ratio of switching elements Q1p and Q5 increases as | Vac | decreases. Therefore, the change of the current value with respect to the time axis in the actual current Iac is made close to a sine wave, and the phase difference between the output voltage of the AC power supply 2 and the actual current Iac is made close to zero.
(Step S151)
First, the switching element Q1p is turned off, the switching elements Q2p and Q4p are turned on, and the switching elements Q3p and Q5 are switched in synchronization. That is, switching element Q3p is turned on and switching element Q5 is turned on at the same timing, and switching element Q3p is turned off and switching element Q5 is turned off at the same timing. When switching the switching elements Q3p, Q5, the ON period and the OFF period of the switching elements Q3p, Q5 are set so that the actual current Iac approaches the required current Iac ′.

  First, when the switching elements Q3p and Q5 are turned on, the current from the negative electrode of the AC power source 2 is changed to the low-pass filter 10, the switching element Q4p, the current sensor 53, the reactor 30, and the switching element as indicated by the arrows of Mode 3 in FIG. It flows to the positive electrode of AC power supply 2 through Q5, Q3p, and low-pass filter 10. At this time, energy is stored in the reactor 30.

  Further, when the switching elements Q3p and Q5 are turned off, as shown by the arrows of Mode 4 in FIG. 12, the current is converted into the reactor 30, the diode D1, the DC load 3, the switching elements Q2p and Q4p based on the energy stored in the reactor 30. And through the current sensor 53.

  Such switching elements Q3p and Q5 are turned on and switching elements Q3p and Q5 are turned off repeatedly. At this time, (VB / (| Vac | + VB)) is used as the duty ratio of the switching elements Q3p and Q5. Therefore, the duty ratio of switching elements Q3p and Q5 decreases as | Vac | increases, and the duty ratio of switching elements Q3p and Q5 increases as | Vac | decreases. For this reason, the change of the current value with respect to the time axis in the actual current Iac is made close to a sine wave, and the phase difference between the output voltage of the AC power supply 2 and the actual current Iac is made close to zero.

  In steps S150 and S151, the switching element Q2p serves as a rectifier diode.

  In the present embodiment described above, when the control device 50 performs the charge control, the ON voltage is generated as a loss in three elements among the switching elements Q1p to Q4p, Q5 and the diode D1. Therefore, similarly to the first embodiment described above, in the power conversion device 1 that converts the AC power of the AC power supply 2 into DC power, it is possible to reduce the loss that occurs as the ON voltage.

  In the present embodiment, by controlling the switching elements Q1p to Q4p, Q5, the change of the current value with respect to the time axis in the actual current Iac is brought close to a sine wave, and the output voltage of the AC power supply 2 and the actual current Iac are The phase difference between them will be close to zero. For this reason, the power factor of the alternating current power output from the alternating current power supply 2 can be brought close to 1.

(Third embodiment)
In the above-described second embodiment, the example in which the switching elements Q1p and Q5 (Q3p, Q5) are switched synchronously in the step-up / step-down control in step S150 (S151) in FIG. 9 has been described. An example will be described in which the elements Q1p and Q5 (Q3p and Q5) are switched asynchronously to perform the buck-boost control.

  Hereinafter, the step-up / step-down control in step S150 (S151) of the present embodiment will be described with reference to FIGS.

13A is a timing chart showing the relationship between the absolute value | Vac | of the output voltage of the power supply voltage 2 and the voltage VB between both electrodes of the DC load 3, and FIGS. 13B to 13F show the switching element Q1p. , Q2p, Q3p, Q4p, Q5 is a timing chart showing on and off timings. 14 and 15 are circuit diagrams illustrating the flow of current in the power conversion device 1.
(Step S150)
First, the switching element Q3p is turned off, the switching elements Q2p and Q4p are turned on, and the switching elements Q1p and Q5 are switched. The ON period and the OFF period of the switching elements Q1p and Q5 are set so that the actual current Iac approaches the required current Iac ′.

  First, when the switching elements Q1p and Q5 are turned on, the current from the positive electrode of the AC power source 2 is changed to the low-pass filter 10, the switching element Q1p, the current sensor 53, the reactor 30, and the switching element as indicated by the arrow of Mode 1 in FIG. It flows to the negative electrode of AC power supply 2 through Q5, Q2p, and low-pass filter 10. At this time, energy is stored in the reactor 30.

  After that, when the switching elements Q1p and Q5 are turned off, as shown by the arrows of Mode 2 in FIG. 14, the current is changed to the reactor 30, the diode D1, the DC load 3, the switching elements Q2p and Q4p based on the energy stored in the reactor 30. And through the current sensor 53.

  Further, when the switching element Q1p is turned off and the switching element Q5 is turned on, as shown by the arrow of Mode 3 in FIG. 14, the current is changed to the reactor 30, the switching element Q5p, and the switching element Q2p based on the energy stored in the reactor 30. , Q4p and the current sensor 53.

  As a result of such switching of the switching elements Q1p and Q5, a current flows into the DC load 3 and DC power is stored.

Here, the duty ratio of the switching element Q1p is set to a constant value D. The constant value D is set so that | Vac | × D is smaller than VB. | Vac | is the absolute value of the output voltage Vac of the AC power supply 2 (= the detection voltage of the voltage sensor 51). VB is a voltage between the plus electrode and the minus electrode of the DC load 3. The duty ratio of switching element Q5 is set to {1- (| Vac | × D) / VB}. Therefore, as | Vac | increases, the duty ratio of the switching element Q5 decreases, and as | Vac | decreases, the duty ratio of the switching element Q5 increases. Therefore, the change of the current value with respect to the time axis in the actual current Iac is made close to a sine wave, and the phase difference between the output voltage of the AC power supply 2 and the actual current Iac is made close to zero.
(Step S151)
First, the switching element Q1p is turned off, the switching elements Q2p and Q4p are turned on, and the switching elements Q3p and Q5 are switched. The ON period and OFF period of the switching elements Q3p, Q5 are set so that the actual current Iac approaches the required current Iac ′.

  First, when the switching elements Q3p and Q5 are turned on, the current from the negative electrode of the AC power supply 2 is changed to the low-pass filter 10, the switching element Q4p, the current sensor 53, the reactor 30, and the switching element as indicated by the arrows of Mode 4 in FIG. It flows to the positive electrode of AC power supply 2 through Q5, Q3p, and low-pass filter 10. At this time, energy is stored in the reactor 30.

  Further, when the switching elements Q3p and Q5 are turned off, as shown by the arrows of Mode 5 in FIG. 15, the current is changed to the reactor 30, the diode D1, the DC load 3, the switching elements Q2p and Q4p based on the energy stored in the reactor 30. And through the current sensor 53.

  After that, when the switching element Q3p is turned off and the switching element Q5 is turned on, the current is changed to the reactor 30, the switching elements Q5, Q2p, based on the energy stored in the reactor 30, as indicated by the arrow of Mode 6 in FIG. It flows through Q4p and the current sensor 53.

  As a result of such switching of the switching elements Q3p and Q5, a current flows into the DC load 3 and DC power is stored.

  Here, the duty ratio of the switching element Q3p is set to a constant value D. The constant value D is set so that | Vac | × D is smaller than VB, as in step S150. The duty ratio of switching element Q5 is set to {1- (| Vac | × D) / VB}. Therefore, as | Vac | increases, the duty ratio of the switching element Q5 decreases, and as | Vac | decreases, the duty ratio of the switching element Q5 increases. Therefore, the change of the current value with respect to the time axis in the actual current Iac is made close to a sine wave, and the phase difference between the output voltage of the AC power supply 2 and the actual current Iac is made close to zero.

  In the present embodiment described above, three elements among the switching elements Q1p to Q4p, Q5 and the diode D1 are energized when the control device 50 performs the charge control. For this reason, when the control apparatus 50 performs charge control, a loss arises as an ON voltage in three elements. Therefore, similarly to the first embodiment described above, in the power conversion device 1 that converts the AC power of the AC power supply 2 into DC power, it is possible to reduce the loss that occurs as the ON voltage.

  In the present embodiment, similarly to the second embodiment described above, the switching elements Q1p to Q4p, Q5 are controlled so that the change in the current value with respect to the time axis in the actual current Iac approximates a sine wave, and the AC power supply 2 The phase difference between the output voltage and the actual current Iac will be close to zero. As a result, the power factor of the AC power output from the AC power supply 2 can be made close to 1.

  In the third embodiment, when the output voltage Vac of the power supply voltage 2 is less than zero, in step S151, the switching element Q1p is turned off, the switching elements Q2p, Q4p are turned on, and the switching elements Q3p, Q5 are switched. Although an example is shown, instead of this, in step S151, the switching elements Q1p and Q3p may be turned on, the switching element Q2p may be turned off, and the switching elements Q4p and Q5 may be switched.

  In this case, the ON period and the OFF period of the switching elements Q3p and Q5 are set so that the actual current Iac approaches the required current Iac '.

  First, when the switching elements Q4p and Q5 are turned on, the current from the negative electrode of the AC power supply 2 is exchanged through the low-pass filter 10, the switching element Q4p, the current sensor 53, the reactor 30, the switching elements Q5, Q3p, and the low-pass filter 10. It flows to the positive electrode of the power supply 2. At this time, energy is stored in the reactor 30.

  When switching elements Q4p and Q5 are turned off, current flows through reactor 30, diode D1, DC load 3, switching elements Q3p and Q1p, and current sensor 53 based on the energy stored in reactor 30.

  Thereafter, when switching element Q4p is turned off and switching element Q5 is turned on, current flows through reactor 30, switching elements Q5, Q3p, Q1p, and current sensor 53 based on the energy stored in reactor 30.

  As a result of such switching of the switching elements Q4p and Q5, a current flows into the DC load 3 and DC power is stored.

  Here, the duty ratio of the switching element Q4p is set to a constant value D. The constant value D is set so that | Vac | × D is smaller than VB, as in step S150. The duty ratio of switching element Q5 is set to {1- (| Vac | × D) / VB}. Therefore, as | Vac | increases, the duty ratio of the switching element Q5 decreases, and as | Vac | decreases, the duty ratio of the switching element Q5 increases. Therefore, the change of the current value with respect to the time axis in the actual current Iac is made close to a sine wave, and the phase difference between the output voltage of the AC power supply 2 and the actual current Iac is made close to zero.

(Fourth embodiment)
In the first to third embodiments described above, the example using the bridge circuit including the four switching elements has been described. Instead, in the present embodiment, the example using the bridge circuit including the six switching elements is described. explain.

  FIG. 16 shows a circuit configuration of the power conversion device 1 of the present embodiment.

  The power conversion device 1 of this embodiment includes a low-pass filter 10, a bridge circuit 20 </ b> A, a reactor 30, a smoothing capacitor 40, a control device 50, voltage sensors 51 and 52, and a current sensor 53. In FIG. 16, the same reference numerals as those in FIG.

  In the power conversion device 1 of the present embodiment, the switching element Q5 and the diodes D1 and D5 in FIG. 1 are not used, and a bridge circuit 20A is used instead of the bridge circuit 20 in FIG.

  The bridge circuit 20A includes switching elements Q1p, Q2p, Q3p, Q4p, Q5p, and Q6p. Switching elements Q1p and Q2p are connected in series between the positive electrode and the negative electrode of AC power supply 2. Of the switching elements Q1p and Q2p, the switching element Q1p is located on the positive electrode side of the AC power supply 2, and of the switching elements Q1p and Q2p, the switching element Q2p is located on the negative electrode side of the AC power supply 2.

  Switching elements Q3p and Q4p are connected in series between the plus electrode and minus electrode of DC load 3. Of the switching elements Q3p and Q4p, the switching element Q3p is located on the positive electrode side of the DC load 3, and of the switching elements Q3p and Q4p, the switching element Q4p is located on the negative electrode side of the DC load 3.

  Switching element Q5p is arranged between the collector terminal of switching element Q1p and the emitter terminal of switching element Q3p. Switching element Q6p is arranged between the collector terminal of switching element Q2p and the emitter terminal of switching element Q4p.

  In the present embodiment, for example, insulated gate bipolar transistors are used as the switching elements Q1p, Q2p, Q3p, Q4p, Q5p, and Q6p. As the switching elements Q1p, Q2p, Q3p, Q4p, Q5p, and Q6p, elements that can endure even when a high reverse voltage is applied between the collector terminal and the emitter terminal are used.

  Reactor 30 is arranged between a common connection terminal between switching elements Q1p and Q2p and a common connection terminal between switching elements Q3p and Q4p. Current sensor 53 is arranged between reactor 30 and a common connection terminal between switching elements Q3p and Q4p.

  Next, charging control of the control device 50 of the present embodiment will be described.

  FIG. 17 is a flowchart showing charge control of the control device 50. 18A is a timing chart showing the relationship between the absolute value | Vac | of the output voltage of the AC power supply 2 and the output voltage VB of the DC load, and FIGS. 18B to 18G are switching elements Q1p, Q2p, Q3p. , Q4p, Q5p, Q6p is a timing chart showing on and off timing. 19 and 20 are circuit diagrams illustrating the flow of current in the power conversion device 1.

In FIG. 17, step 150a (step-up / step-down control) replacing step 150 and step 151a (step-up / step-down control) replacing step 151 in FIG. 9 are used. Hereinafter, steps 150a and 151a will be described separately.
(Step 150a)
First, the switching element Q5p is turned off, the switching elements Q2p, Q3p, and Q6p are turned on, and the switching elements Q1p and Q4p are switched in synchronization. That is, switching element Q1p is turned on and switching element Q4p is turned on at the same timing, and switching element Q1p is turned off and switching element Q4p is turned off at the same timing.

  First, when the switching elements Q1p and Q4p are turned on, the current from the positive electrode of the AC power source 2 is changed to the low-pass filter 10, the switching element Q1p, the reactor 30, the current sensor 53, and the switching element as indicated by the arrows of Mode1 in FIG. It flows to the negative electrode of AC power supply 2 through Q4p, Q6p, and low-pass filter 10. At this time, the reactor 30 stores energy.

  Further, when the switching elements Q1p and Q4p are turned off, as shown by the arrows of Mode 2 in FIG. 19, the current is based on the energy stored in the reactor 30, the current is supplied to the reactor 30, the current sensor 53, the switching element Q3p, the DC load 3, And flows through the switching elements Q6p, Q2p. At this time, energy is stored in the DC load 3.

  Such switching elements Q1p and Q4p are turned on and switching elements Q1p and Q4p are turned off repeatedly. At this time, the ON period and the OFF period of the switching elements Q1p and Q4p are set so that the actual current Iac approaches the required current Iac '. As the duty ratio of the switching elements Q1p and Q4p, (VB / (| Vac | + VB)) is used. Therefore, the duty ratio of switching elements Q1p and Q4p decreases as | Vac | increases, and the duty ratio of switching elements Q1p and Q4p increases as | Vac | decreases. Therefore, the change of the current value with respect to the time axis in the actual current Iac approaches a sine wave shape, and the phase difference between the output voltage of the AC power supply 2 and the actual current Iac approaches zero.

In step 150a, the switching elements Q1p and Q4p perform switching control of the step-up / step-down PFC circuit, and the switching elements Q2p, Q3p, and Q6p serve as rectifier diodes.
(Step 151a)
First, the switching elements Q1p, Q4p are turned off, the switching elements Q2p, Q3p, Q6p are turned on, and the switching element Q5p is switched.

  First, when the switching element Q5p is turned on, as indicated by an arrow of Mode 3 in FIG. 20, the current from the negative electrode of the AC power supply 2 is changed to the low-pass filter 10, the switching element Q2p, the reactor 30, the current sensor 53, the switching element Q3p, It flows to the positive electrode of the AC power supply 2 through Q5p and the low-pass filter 10. At this time, energy is stored in the reactor 30.

  Further, when the switching element Q5p is turned off, as shown by the arrow of Mode 4 in FIG. 20, the current is based on the energy stored in the reactor 30, the current is the reactor 30, the current sensor 53, the switching element Q3p, the DC load 3, and the switching. It flows through the elements Q6p and Q2p. At this time, energy is stored in the DC load 3.

  Such switching element Q5p is repeatedly turned on and off. At this time, the ON period and the OFF period of the switching element Q5p are set so that the actual current Iac approaches the required current Iac '. As the duty ratio of switching element Q5, (VB / (| Vac | + VB)) is used. Therefore, the duty ratio of switching element Q5 decreases as | Vac | increases, and the duty ratio of switching element Q5p increases as | Vac | decreases. For this reason, the change of the current value with respect to the time axis in the actual current Iac approaches a sine wave shape, and the phase difference between the output voltage of the AC power supply 2 and the actual current Iac approaches zero.

  In step 151a, the switching element Q5p performs switching control of the step-up / step-down PFC circuit, and the switching elements Q2p, Q3p, and Q6p serve as rectifier diodes.

  In the present embodiment described above, when the control device 50 performs the charge control, the switching elements Q1p, Q4p, Q6p or the switching elements Q2p, Q3p, Q6p are energized in step 150a, and the switching element Q1p is switched in step 151a. Q2p, Q3p, Q5p or switching elements Q2p, Q3p, Q6p are energized. For this reason, when the control device 50 performs the charge control, the ON voltage is generated as a loss in the three switching elements. Therefore, similarly to the first embodiment described above, in the power conversion device 1 that converts the AC power of the AC power supply 2 into DC power, it is possible to reduce the loss that occurs as the ON voltage.

  In the present embodiment, the switching elements Q1p to Q6p are controlled so that the change in the current value with respect to the time axis in the actual current Iac approximates a sine wave, and between the output voltage of the AC power supply 2 and the actual current Iac. The phase difference will be close to zero. As a result, the power factor of the AC power output from the AC power supply 2 can be made close to 1.

(Fifth embodiment)
In the first to fourth embodiments described above, the example in which the charging control for converting AC power to DC power has been described, but instead, in the fifth embodiment, the reverse of converting DC power to AC power. An example in which power flow control is performed will be described.

  FIG. 21 shows a circuit configuration of the power conversion device 1 of the present embodiment.

  The power conversion device 1 of this embodiment includes a low-pass filter 10, a bridge circuit 20B, a reactor 30, switching elements Q5 and Q6, diodes D1 and D2, a smoothing capacitor 40, a control device 50, voltage sensors 51 and 52, and a current sensor 53. It is composed of In FIG. 21, the same reference numerals as those in FIG.

  21 uses a bridge circuit 20B instead of the bridge circuit 20 in FIG. 1, and a switching element Q6 is added.

  The bridge circuit 20B includes switching elements Q1n, Q2n, Q3n, and Q4n.

  The switching element Q1n of the bridge circuit 20B has an emitter terminal and a collector terminal arranged in opposite directions with respect to the switching element Q1p of the bridge circuit 20. Similarly, the switching elements Q2n, Q3n, and Q4n of the bridge circuit 20B have their emitter terminals and collector terminals arranged in opposite directions with respect to the switching elements Q2p, Q3p, and Q4p of the bridge circuit 20, respectively.

  The switching element Q2n corresponds to the switching element Q2p, the switching element Q3n corresponds to the switching element Q3p, and the switching element Q4n corresponds to the switching element Q4p. As the switching elements Q1n, Q2n, Q3n, and Q4n, elements that can endure even when a high reverse voltage is applied between the collector terminal and the emitter terminal are used.

  Switching element Q6 is arranged in antiparallel to diode D1 between reactor 30 and the positive electrode of capacitor 30 (battery 4).

  In FIG. 21, an AC load 5 is used instead of the AC power source 2 of FIG. 1, and a battery 4 is used instead of the DC load 4 of FIG. The voltage sensor 51 detects the voltage between the positive electrode and the negative electrode of the AC load 5. The voltage sensor 52 detects the voltage between the positive electrode and the negative electrode of the battery 4.

  The control device 50 performs reverse power flow processing for converting the DC power of the battery 4 into AC power and applying the AC power to the AC load 5. The control device 50 performs switching control of the switching elements Q1n, Q2n, Q3n, Q4n, Q5, and Q6 based on the output signals of the sensors 51, 52, and 53 when performing reverse power flow processing.

  Next, reverse power flow control of the control device 50 of the present embodiment will be described with reference to FIGS.

  FIG. 22 is a flowchart showing the reverse power flow control process of the control device 50, and FIG. 23 (a) shows the relationship between the absolute value | Vac | of both electrodes of the AC load 5 and the voltage VB between both electrodes of the battery 4. The timing charts shown in FIGS. 23B to 23G are timing charts showing the ON and OFF timings of the switching elements Q1n, Q2n, Q3n, Q4n, Q5, and Q6. 24 to 27 are circuit diagrams illustrating the flow of current in the power conversion device 1.

  When receiving a command to start reverse flow control from the electronic control unit 60, the control device 50 starts executing reverse flow control processing according to the flowchart of FIG.

  In the flowchart of FIG. 22, steps S130a to S133a are used instead of steps S130 to S133 in the flowchart of FIG. Step S130a corresponds to step S130, step S131a corresponds to step S131, step S132a corresponds to step S132, and step S133a corresponds to step S133.

Hereinafter, the processing of steps S130a to S133a will be described separately (step S130a: step-down control).
Switching elements Q1n, Q2n, Q4n are turned on, switching elements Q3n, Q5 are turned off, and switching control is performed on switching element Q6.

  First, when the switching element Q6 is turned on, the current from the positive electrode of the battery 4 is switched to the switching element Q6, the reactor 30, the current sensor 53, the switching element Q1n, the low-pass filter 10, and the alternating current as indicated by the arrow of Mode1 in FIG. It flows to the load 5, the low-pass filter 10, the switching element Q2n, and the negative electrode of the battery 4. At this time, energy is stored in the reactor 30.

  Next, when the switching element Q6 is turned off, as shown by the arrow of Mode 2 in FIG. 24, the current is based on the energy stored in the reactor 30, the current is the reactor 30, the current sensor 53, the switching element Q1n, the low-pass filter 10, the AC The current flows through the load 5, the low-pass filter 10, the switching element Q2n, and the diode D2.

Such switching element Q6 is repeatedly turned on and off. At this time, the duty ratio of switching element Q6 is set to | Vac | / VB. | Vac | is an absolute value of the voltage Vac between both electrodes of the AC load 5. For this reason, the duty ratio of the switching element Q6 increases as | Vac | increases, and the duty ratio of the switching element Q6 decreases as | Vac | decreases. Therefore, the change of the current value with respect to the time axis in the current Iac is brought close to a sine wave shape, and the phase difference between the voltage between both electrodes of the AC load 5 and the current Iac is brought close to zero. In this case, the current Iac is a current that flows through the low-pass filter 10 between the bridge circuit 20 and the AC load 5.
(Step S131a: Boost control)
First, switching elements Q1n, Q2n, Q6 are turned on, switching elements Q5n, Q3n are turned off, and switching control is performed on switching element Q4n.

First, when the switching element Q4 is turned off , the switching element Q6, the reactor 30, and the like, based on the energy stored in the reactor 30 between the positive electrode and the negative electrode of the battery 4 as indicated by the arrows of Mode 4 in FIG. It flows through the current sensor 53, the switching element Q1n, the low-pass filter 10, the AC load 5, the low-pass filter 10, and the switching element Q2n.

Further, when the switching element Q4 is turned on, as indicated by the arrow of Mode 3 in FIG. 25, the current flows between the positive electrode and the negative electrode of the battery 4, the reactor 30, the current sensor 53, the switching element Q4n, the switching element Q2n, and It flows through the battery 4 and stores energy in the reactor 30.

  Such switching element Q4 is repeatedly turned on and off. At this time, the duty ratio of the switching element Q4 is set to (1-VB / | Vac |). Therefore, the duty ratio of the switching element Q1 increases as | Vac | increases, and the duty ratio of the switching element Q4 decreases as | Vac | decreases. Therefore, the change of the current value with respect to the time axis in the current Iac is brought close to a sine wave shape, and the phase difference between the voltage between both electrodes of the AC load 5 and the current Iac is brought close to zero.

(Step S132a: Step-down control)
First, switching elements Q3n, Q4n are turned on, switching elements Q1n, Q2n, Q5 are turned off, and switching control is performed on switching element Q6.

  When the switching element Q6 is turned on, the current from the positive electrode of the battery 4 is changed to the switching element Q6, the reactor 30, the current sensor 53, the switching element Q4n, the low-pass filter 10, and the AC load 5 as indicated by the arrow of Mode 5 in FIG. , Flows through the low-pass filter 10 and the switching element Q3n to the negative electrode of the battery 4. At this time, energy is stored in the reactor 30.

  When the switching element Q6 is turned off, the reactor 30, the current sensor 53, the switching element Q4n, the low-pass filter 10, the AC load 5, based on the energy stored in the reactor 30, as indicated by the arrow of Mode 6 in FIG. It flows through the low-pass filter 10, the switching element Q3n, and the diode D2.

  Here, the duty ratio of the switching element Q6 is set to | Vac | / VB as in step S130a. For this reason, the duty ratio of the switching element Q6 increases as | Vac | increases, and the duty ratio of the switching element Q6 decreases as | Vac | decreases. For this reason, the change of the current value with respect to the time axis in the current Iac flowing through the AC load 5 is made close to a sine wave, and the phase difference between the voltage between both electrodes of the AC load 5 and the current Iac is made close to zero. Become.

(Step S133a: Boost control)
First, switching elements Q3n, Q4n, and Q6 are turned on, switching elements Q2n and Q5 are turned off, and switching control is performed on switching element Q1.

  When the switching element Q1 is turned on, the current from the positive electrode of the battery 4 passes through the switching element Q6, the reactor 30, the current sensor 53, the switching elements Q1n and Q3n, as indicated by the arrow of Mode 7 in FIG. Flowing into. At this time, energy is stored in the reactor 30.

  When the switching element Q1 is turned off, the switching element Q6, the reactor 30, the current sensor 53, the switching element Q4n, the low-pass filter 10, based on the energy stored in the reactor 30, as indicated by the arrow of Mode 8 in FIG. It flows through AC load 5, low-pass filter 10, switching element Q3n, and battery 4.

  Here, the duty ratio of the switching element Q1 is set to (1-VB / | Vac |). Therefore, the duty ratio of the switching element Q1 increases as | Vac | increases, and the duty ratio of the switching element Q4 decreases as | Vac | decreases. Therefore, the change of the current value with respect to the time axis in the current Iac flowing through the AC load 5 is made close to a sine wave, and the phase difference between the voltage between both electrodes of the AC load 5 and the current Iac is made close to zero. .

  A current flows through the AC load 5 by the processing of steps S130a to S133a. As a result, the DC power of the battery 4 is converted into AC power and supplied to the AC load 5.

  In the present embodiment described above, three elements among the switching elements Q1n to Q4n, Q5, and Q6 are energized when the control device 50 performs the reverse power flow control. For this reason, when the control device 50 performs the charge control, the ON voltage is generated as a loss in the three switching elements. Therefore, in the power converter 1 that converts the DC power of the battery 4 into AC power, it is possible to reduce the loss that occurs as the ON voltage. For this reason, the efficiency of power conversion can be improved.

  In the present embodiment, the switching elements Q1n, Q2n, Q3n, Q4n, Q5, and Q6 are controlled so that the change in the current value with respect to the time axis in the current Iac flowing through the AC load 5 approaches a sine wave shape and the AC load 5 The phase difference between the voltage between both electrodes and the current Iac is brought close to zero. For this reason, by making the power factor of the AC power applied to the AC load 5 close to 1, power conversion from DC power to AC power can be efficiently performed.

(Sixth embodiment)
In the sixth embodiment, an example will be described in which reverse power flow control is performed by switching control of the switching elements Q1, Q6 (or Q3, Q6) in the circuit configuration of the power conversion device 1 of FIG.

  Hereinafter, reverse power flow control of the control device 50 of the present embodiment will be described with reference to FIGS. 28 to 31.

  FIG. 28 is a flowchart showing the reverse power flow control of this embodiment, and FIG. 29A is a timing showing the relationship between the absolute value | Vac | of the voltage across the AC load 5 and the voltage VB across the battery 4. FIGS. 29B to 29G are timing charts showing the on / off timings of the switching elements Q1n, Q2n, Q3n, Q4n, Q5, and Q6. 30 and 31 are circuit diagrams illustrating the flow of current in the power conversion device 1.

  The flowchart of FIG. 28 uses steps S150b and S151b in place of steps S150 and S151 in the flowchart of FIG. Step S150b corresponds to step S150, and step S151b corresponds to step S150. Hereinafter, the processes of steps S150b and S151b will be described separately.

(Step S150b)
Switching elements Q1n and Q2n are turned on, switching elements Q3n and Q5n are turned off, and switching control is performed on switching elements Q4n and Q6.

First, when the switching elements Q1n and Q2n are turned on and the switching elements Q4n and Q6 are turned on, the current from the positive electrode of the battery 4 is switched to the switching element Q6, the reactor 30, and the current sensor as indicated by the arrows of Mode1 in FIG. 53, the switching elements Q4n, Q2n, and the negative electrode of the battery 4. At this time, energy is stored in the reactor 30.

Next, when the switching elements Q1n and Q2n are turned on and the switching elements Q4n and Q6 are turned off, the current is passed through the reactor 30 and the current sensor as indicated by the arrows of Mode 2 in FIG. 30 based on the energy stored in the reactor 30. 53, a current flows through the switching element Q1n, the low-pass filter 10, the AC load 5, the low-pass filter 10, the switching element Q2n, and the diode D2.

  Thereafter, when the switching elements Q1n and Q6 are turned off, the current is changed to the reactor 30, the current sensor 53, the switching elements Q4n and Q2n, and the diode D2 based on the energy stored in the reactor 30, as indicated by the arrows of Mode 3 in FIG. Current flows through.

  The duty ratio of switching element Q4n is set to a constant value D. The constant value D is set so that | Vac | × D is smaller than VB. The duty ratio of switching element Q6 is set to {| Vac | / (VB × (1-D))}. Therefore, as | Vac | increases, the duty ratio of switching element Q6 increases, and as | Vac | decreases, the duty ratio of switching element Q6 decreases. For this reason, the change of the current value with respect to the time axis in the current Iac flowing through the AC load 5 is brought close to a sine wave, and the phase difference between the voltage between both electrodes of the AC load 5 and the current Iac is brought close to zero. .

(Step S151b)
Switching elements Q3n and Q4n are turned on, switching elements Q1n and Q5 are turned off, and switching control is performed on switching elements Q2n and Q6.

First, when the switching elements Q3n and Q4n are turned on and the switching elements Q2n and Q6 are turned on, the current from the positive electrode of the battery 4 is switched to the switching element Q6, the reactor 30, and the current sensor as indicated by the arrow of Mode 4 in FIG. 53, the switching elements Q4n, Q2n, and the negative electrode of the battery 4. At this time, energy is stored in the reactor 30.

Next, when the switching elements Q3n and Q4n are turned on and the switching elements Q2n and Q6 are turned off, the current is passed through the reactor 30 and the current sensor as indicated by the arrows of Mode 5 in FIG. 31 based on the energy stored in the reactor 30. 53, a current flows through the switching element Q4n, the low-pass filter 10, the AC load 5, the low-pass filter 10, the switching element Q3n, and the diode D2.

  Thereafter, when the switching element Q3n is turned off and the switching element Q6 is turned on, the current from the positive electrode of the battery 4 is switched to the switching element Q6, the reactor 30, the current sensor 53, the switching element as indicated by the arrow of Mode 6 in FIG. It flows to Q4n, Q2n and the negative electrode of battery 4. At this time, energy is stored in the reactor 30.

  The duty ratio of switching element Q2n is set to a constant value D. The constant value D is set so that | Vac | × D is smaller than VB. The duty ratio of switching element Q6 is set to {| Vac | / (VB × (1-D))}. Therefore, as | Vac | increases, the duty ratio of switching element Q6 increases, and as | Vac | decreases, the duty ratio of switching element Q6 decreases. For this reason, the change of the current value with respect to the time axis in the current Iac flowing through the AC load 5 is made close to a sine wave, and the phase difference between the output voltage of the AC power supply 2 and the current Iac is made close to zero.

  According to the present embodiment described above, when the control device 50 performs reverse power flow control, the ON voltage is generated as a loss in three elements among the switching elements Q1n to Q4n, Q5, Q6 and the diode D2. Therefore, similarly to the fifth embodiment, in the power conversion device 1 that converts the DC power of the battery 4 into AC power, it is possible to reduce the loss that occurs as the ON voltage. For this reason, the efficiency of power conversion can be improved.

  In the present embodiment, the switching elements Q1n, Q2n, Q3n, Q4n, Q5, and Q6 are controlled so that the change in the current value with respect to the time axis in the current Iac flowing through the AC load 5 approaches a sine wave shape and the AC load 5 The phase difference between the voltage between both electrodes and the current Iac is brought close to zero. For this reason, the power factor of the alternating current power given to the alternating current load 5 can be brought close to 1, as in the fifth embodiment.

(Seventh embodiment)
In the fifth and sixth embodiments, the example in which the reverse power flow control is performed in the power conversion device 1 including the bridge circuit including the four switching elements has been described. Instead, in the seventh embodiment, An example in which reverse power flow control is performed in the power conversion device 1 including a bridge circuit including six switching elements will be described.

  FIG. 32 shows a circuit configuration of the power conversion device 1 of the present embodiment.

  The power conversion device 1 of this embodiment includes a low-pass filter 10, a bridge circuit 20 </ b> C, a reactor 30, a smoothing capacitor 40, a control device 50, voltage sensors 51 and 52, and a current sensor 53.

  32 shows the same reference numerals in FIG. 16, and FIG. 37 has a configuration using a bridge circuit 20C in place of the bridge circuit 20A in FIG. For this reason, the description of the bridge circuit 20C will be described below, except for the description of the bridge circuit 20C.

  The bridge circuit 20C includes switching elements Q1n, Q2n, Q3n, Q4n, Q5n, and Q6n.

  Switching element Q1n corresponds to switching element Q1p in FIG. 16, switching element Q2n corresponds to switching element Q2p in FIG. 16, switching element Q3n corresponds to switching element Q3p in FIG. 16, and switching element Q4n corresponds to switching element in FIG. The switching element Q5n corresponds to the element Q4p, the switching element Q5n corresponds to the switching element Q5p in FIG. 16, and the switching element Q6n corresponds to the switching element Q6p in FIG.

  Switching elements Q1n and Q1p have emitter terminals and collector terminals arranged in opposite directions. Similarly, switching elements Q2n and Q2p have emitter terminals and collector terminals arranged in opposite directions. Switching elements Q3n... Q6n and switching elements Q3p... Q6p have emitter terminals and collector terminals arranged in opposite directions.

  As the switching elements Q1n, Q2n, Q3n, Q4n, Q5n, and Q6n of this embodiment, elements that can withstand even when a high reverse voltage is applied between the collector terminal and the emitter terminal are used.

  32, a battery 4 is provided instead of the DC load 3 of FIG. 16, and an AC load 5 is provided instead of the AC power source 2 of FIG. The voltage sensor 51 detects the voltage between the positive electrode and the negative electrode of the AC load 5. The voltage sensor 52 detects the voltage between the positive electrode and the negative electrode of the battery 4.

  The control device 50 executes reverse power flow control for converting the direct current power of the battery 4 into alternating current power and applying it to the alternating current load 5. When executing reverse power flow control, control device 50 performs switching control of switching elements Q1n, Q2n, Q3n, Q4n, Q5n, and Q6n in accordance with the output signals of sensors 51, 52, and 53.

  Next, reverse power flow control of the control device 50 of the present embodiment will be described with reference to FIGS.

  FIG. 33 is a flowchart showing the reverse power flow control of the present embodiment, and FIG. 34A is a timing showing the relationship between the absolute value | Vac | of the voltage across the AC load 5 and the voltage VB across the battery 4. Charts (b) to (g) of FIG. 34 are timing charts showing the on / off timings of the switching elements Q1n, Q2n, Q3n, Q4n, and Q5n. 35 and 36 are circuit diagrams illustrating the flow of current in the power conversion device 1. FIG.

  The flowchart of FIG. 33 is configured to use steps S150b and S151b in place of steps S150a and S151a in the flowchart of FIG. Step S150b corresponds to step S150a, and step S151b corresponds to step S151a. Hereinafter, the processes of steps S150b and S151b will be described separately.

(Step S150b: Buck-Boost Control)
First, the switching element Q5n is turned off, the switching elements Q1n, Q4n, and Q6n are turned on, and the switching elements Q2n and Q3n are switched in synchronization. That is, switching element Q2n is turned on and switching element Q3n is turned on at the same timing, and switching element Q2n is turned off and switching element Q3n is turned off at the same timing.

  First, when the switching elements Q2n and Q3n are turned on, as indicated by the arrow of Mode 2 in FIG. 35, the current flows from the positive electrode of the battery 4 through the switching element Q3n, the current sensor 53, the reactor 30, and the switching elements Q2n and Q6n. Flows to the negative electrode. At this time, energy is stored in the reactor 30.

  Next, when the switching elements Q2n and Q3n are turned off, the current is switched to the switching element Q1n, the low-pass filter 10, the AC load 5, and the low-pass filter based on the energy stored in the reactor 30 as indicated by the arrows of Mode1 in FIG. 10, flows through the switching elements Q6n, Q4n, and the current sensor 53.

Such switching elements Q2n and Q3n are repeatedly turned on and off. At this time, (| Vac | / (| Vac | + VB)) is used as the duty ratio of the switching elements Q2p and Q3n. Therefore, as | Vac | increases, the duty ratio of switching elements Q2p and Q3n increases, and as | Vac | decreases, the duty ratio of switching elements Q2p and Q3n increases. Therefore, the change of the current value with respect to the time axis in the current Iac flowing through the AC load 5 is made close to a sine wave, and the phase difference between the output voltage of the AC load 5 and the current Iac is made close to zero.
(Step S151b: Buck-boost control)
First, the switching element Q1n is turned off, the switching elements Q2n, Q3n, Q4n, and Q5n are turned on, and switching control is performed on the switching element Q6n.

  First, when the switching element Q6n is turned off, as indicated by the arrow of Mode 4 in FIG. 36, current flows from the positive electrode of the battery 4 through the switching element Q3n, the current sensor 53, the reactor 30, and the switching elements Q2n and Q6n. Flowing into. At this time, energy is stored in the reactor 30.

  Next, when the switching element Q6n is turned on, the current is switched to the switching element Q2n, the low-pass filter 10, the AC load 5, the low-pass filter 10, based on the energy stored in the reactor 30, as indicated by the arrow of Mode 3 in FIG. It flows through switching elements Q5n and Q3n and current sensor 53.

  Such switching element Q6n is repeatedly turned on and off. At this time, (| Vac | / (| Vac | + VB)) is used as the duty ratio of switching element Q6n. Therefore, as | Vac | increases, the duty ratio of switching element Q6p increases, and as | Vac | decreases, the duty ratio of switching elements Q2p, Q3n decreases. Therefore, the change of the current value with respect to the time axis in the current Iac flowing through the AC load 5 is made close to a sine wave, and the phase difference between the output voltage of the AC load 5 and the current Iac is made close to zero.

  According to the embodiment described above, three switching elements among the switching elements Q1p to Q6n are energized when the control device 50 performs the reverse power flow control. For this reason, when the control device 50 performs the reverse power flow control, the ON voltage is generated as a loss in the three switching elements. Therefore, in the power converter 1 that converts the DC power of the battery 4 into AC power, it is possible to reduce the loss that occurs as the ON voltage.

  In the present embodiment, the switching elements Q1p, Q2n, Q3n, Q4p, Q5n, and Q6n are subjected to switching control so that the change in the current value with respect to the time axis in the current Iac approximates a sine wave, and the output voltage and current of the AC load 5 The phase difference with Iac will be close to zero. Thereby, since the power factor of the alternating current power given to the alternating current load 5 can be brought close to 1, direct current power can be efficiently converted into alternating current power.

(Eighth embodiment)
In the eighth embodiment, an example in which the power conversion device 1 in FIG. 16 and the power conversion device 1 in FIG. 32 are combined to form a three-phase AC motor control device 6A will be described with reference to FIGS. .

  FIG. 37 shows a circuit configuration of a control device 6A for a three-phase AC motor according to this embodiment.

  The three-phase AC motor control device 6A drives the three-phase AC motor 100, and includes a bridge circuit 20X, a reactor 30, switching elements Q7 and Q8, diodes D7 and D8, a smoothing capacitor 40, a control device 50, a voltage. It comprises sensors 51 and 52, a current sensor 53, and relays SW1, SW2, SW3, and SW4. 37, the same reference numerals as those in FIGS. 16 and 32 denote the same components, and a description thereof will be omitted.

  The bridge circuit 20X includes switching elements Q1, Q2, Q3, Q4, Q5, and Q6.

  The switching element Q1 is composed of the switching element Q1p of FIG. 16 and the switching element Q1n of FIG. 32, the switching element Q2 is composed of the switching element Q2p of FIG. 16 and the switching element Q2n of FIG. 32, and the switching element Q3 is 16 switching elements Q3p and switching element Q3n in FIG. 32. Switching element Q4 is composed of switching element Q4p in FIG. 16 and switching element Q4n in FIG. 32. Switching element Q5 is composed of switching element Q5p in FIG. It is composed of the switching element Q5n of FIG. The switching element Q6 includes the switching element Q6p in FIG. 16 and the switching element Q6n in FIG.

  Switching elements Q7 and Q8 are connected in series between the positive electrode and the negative electrode of battery 3. Of the switching elements Q7 and Q8, the switching element Q7 is located on the positive electrode side of the battery 3, and of the switching elements Q7 and Q8, the switching element Q8 is located on the negative electrode side of the battery 3.

  In the present embodiment, as the switching elements Q7 and Q8, insulated gate bipolar transistors are used similarly to the switching elements Q1n... Q6n, Q1p.

  The diode D7 is disposed in antiparallel with the switching element Q7 between the common connection terminal T1 between the switching elements Q7 and Q8 and the positive electrode of the battery 3. The diode D8 is disposed in antiparallel with the switching element Q8 between the common connection terminal T1 between the switching elements Q7 and Q8 and the negative electrode of the battery 3.

  Relay SW1 is a switch arranged between AC power supply 2 and bridge circuit 20X. The relay SW1 connects or opens the AC power supply 2 and the bridge circuit 20X. A common connection terminal T <b> 1 between the switching elements Q <b> 7 and Q <b> 8 is connected to the first electrode 110 a of the stator coil 110 of the three-phase AC motor 100.

  The relay SW2 is a switch arranged between the common connection terminal T2 between the switching elements Q3 and Q4 and the second electrode 110b of the stator coil 110. The relay SW2 connects or opens between the common connection terminal T2 and the second electrode 110b of the stator coil 110.

  The relay SW3 is a switch connected between the common connection terminal T3 between the switching elements Q1 and Q2 and the third electrode 110c of the stator coil 110. The relay SW3 connects or opens between the common connection terminal T3 and the third electrode 110c of the stator coil 110.

  Relay SW4 is arranged between common connection terminal T3 between switching elements Q1 and Q2 and reactor 30. The relay SW4 connects or opens the common connection terminal T3 and the reactor 30.

  The control device 50 controls the relays SW1 to SW4 to execute any one of motor control, charge control, and reverse power flow control.

  FIG. 38 is a chart showing switching on and off of the relays SW1 to SW4 in motor control, charge control, and reverse power flow control.

  Control device 50 executes motor control when relays SW1 and SW4 are turned off, relays SW2 and SW3 are turned on, and switching elements Q5p, Q5n, Q6p, and Q6n are turned on.

  In the motor control, the switching elements Q1, Q2, Q3, Q4, Q7, and Q8 are switched and output to the stator coil 110 by outputting an alternating current from the common connection terminals T1, T2, and T3 to the stator coil 110. The rotor is rotated by generating a magnetic field. In this case, the switching elements Q1n, Q2n, Q3n, and Q4n serve as rectifier diodes.

  The control device 50 performs charging control or reverse power flow control when the relays SW1 and SW4 are turned on and the relays SW2 and SW3 are turned off.

  When executing the charge control, the control device 50 turns off the switching elements Q1n, Q2n, Q3n, Q4n, Q5n, Q6n, and switches the switching elements Q1p, Q2p, Q3p as in the fourth embodiment. , Q4p, Q5p, Q6p are controlled respectively. Thereby, the alternating current power of alternating current power supply 2 is converted into direct current power, and is given to battery 3 as a direct current load.

  When executing the reverse power flow control, the control device 50 turns off the switching elements Q1p, Q2p, Q3p, Q4p, Q5p, Q6p, Q7, and Q8, as in the above-described seventh embodiment. Q1n, Q2n, Q3n, Q4n, Q5n, and Q6n are controlled. In this case, it is necessary to connect an AC load instead of the AC power source 2 in FIG.

(Ninth embodiment)
In the ninth embodiment, an example in which the power conversion device 1 of FIG. 1 and the power conversion device 1 of FIG. 21 are combined to form a three-phase AC motor control device 6B will be described with reference to FIG. 39 and FIG. .

  FIG. 39 shows a circuit configuration of a control device 6B for a three-phase AC motor according to this embodiment.

  The control device 6B for a three-phase AC motor includes a bridge circuit 20Y, a reactor 30, switching elements Q7 and Q8, diodes D7 and D8, a smoothing capacitor 40, a control device 50, voltage sensors 51 and 52, a current sensor 53, a relay SW1, It consists of SW2, SW3, and SW4. 39, the same reference numerals as those in FIGS. 1 and 21 denote the same components, and the description thereof is omitted.

  The bridge circuit 20Y includes switching elements Q1, Q2, Q3, and Q4.

  The switching element Q1 is composed of the switching element Q1p of FIG. 1 and the switching element Q1n of FIG. 21, the switching element Q2 is composed of the switching element Q2p of FIG. 1 and the switching element Q2n of FIG. 21, and the switching element Q3 is 1 and switching element Q3n in FIG. 21, switching element Q4 is composed of switching element Q4p in FIG. 1 and switching element Q4n in FIG. 21, and switching element Q5 is composed of switching element Q5p in FIG. It is composed of the switching element Q5n of FIG.

  Switching elements Q7 and Q8 are connected in series between the positive electrode and the negative electrode of battery 3. Of the switching elements Q7 and Q8, the switching element Q7 is located on the positive electrode side of the battery 3, and of the switching elements Q7 and Q8, the switching element Q8 is located on the negative electrode side of the battery 3.

  The switching element Q7 is composed of switching elements Q7p and Q7n. Switching elements Q7p and Q7n have emitter terminals and collector terminals arranged in opposite directions.

  The switching element Q8 is composed of switching elements Q8p and Q8n. Switching elements Q8p and Q8n have emitter terminals and collector terminals arranged in opposite directions.

  In this embodiment, as the switching elements Q7n, Q7p, Q8p, and Q8n, insulated gate bipolar transistors are used as in the case of Q1p, Q2p, Q3p, Q4p, Q1n, Q2n, Q3n, and Q4n.

  Switching elements Q7 and Q8 together with switching elements Q1, Q2, Q3, and Q4 constitute an inverter circuit that outputs an alternating current to stator coil 110 of three-phase AC motor 100, as will be described later.

  Relay SW1 is a switch arranged between AC power supply 2 and bridge circuit 20Y. Relay SW1 connects or opens between AC power supply 2 and bridge circuit 20Y.

  A common connection terminal T <b> 1 between the switching elements Q <b> 7 and Q <b> 8 is connected to the first electrode 110 a of the stator coil 110 of the three-phase AC motor 100.

  The relay SW2 is a switch connected between the common connection terminal T2 between the switching elements Q2 and Q4 and the second electrode 110b of the stator coil 110. The relay SW2 connects or opens between the common connection terminal T2 and the second electrode 110b of the stator coil 110.

  The relay SW3 is a switch connected between the common connection terminal T3 between the switching elements Q1 and Q3 and the third electrode 110c of the stator coil 110. The relay SW3 connects or opens between the common connection terminal T3 and the third electrode 110c of the stator coil 110.

  The relay SW4 is a switch arranged between the common connection terminal T4 between the switching elements Q1 and Q4 and the positive electrode of the battery 3. The relay SW4 connects or opens between the common connection terminal T4 and the positive electrode of the battery 3.

  The relay SW5 is a switch arranged between the common connection terminal T4 between the switching elements Q1 and Q4 and the reactor 30. Relay SW5 connects or opens between common connection terminal T4 between switching elements Q1 and Q4 and reactor 30.

  The control device 50 controls the relays SW1 to SW5 to execute any one of motor control, charge control, and reverse power flow control.

  FIG. 40 is a chart showing switching on and off of the relays SW1 to SW5 in motor control, charge control, and reverse power flow control.

  The control device 50 performs motor control when the relays SW2, SW3, and SW4 are turned on and the relays SW1 and SW5 are turned off.

  The motor control is performed by switching the switching elements Q1n, Q2n, Q3n, Q4n, Q7p, and Q8p, so that an alternating current is output from the common connection terminals T1, T2, and T3 to the stator coil 110, and a rotating magnetic field is applied to the stator coil 110. generate. In this case, the switching elements Q1p, Q2p, Q3p, Q4p, Q7n, and Q8n serve as rectifier diodes.

  The control device 50 performs charge control or reverse power flow control when the relays SW1, SW5 are turned on and the relays SW2, SW3, SW4 are turned off.

  When executing the charge control, the control device 50 controls the switching elements Q1p, Q2p, Q3p, Q4p, Q7n, Q8p, and Q8n with the switching elements Q1n, Q2n, Q3n, Q4n, and Q7p turned off, respectively. To do. Switching element Q8p corresponds to switching element Q5 in FIG. Control of the switching elements Q1p, Q2p, Q3p, Q4p, and Q8p is the same as the charge control of the first embodiment described above. Switching element Q7n corresponds to diode D1 in FIG. 1, and switching element Q8n corresponds to diode D2 in FIG.

  When executing reverse power flow control, control device 50 controls switching elements Q1n, Q2n, Q3n, Q4n, Q7p, and Q8n with switching elements Q1p, Q2p, Q3p, Q4p, and Q8p turned off, respectively. . Switching element Q7n corresponds to diode D1 in FIG. 1, and switching element Q7p corresponds to switching element Q6 in FIG. The control of the switching elements Q1n, Q2n, Q3n, Q4n, and Q7p is the same as the reverse power flow control of the fifth embodiment described above.

  In the above-described ninth embodiment, when the control device 50 performs the charging control, the example is described in which the switching elements Q1p, Q2p, Q3p, Q4p, and Q8p are controlled, respectively, as in the first embodiment. Instead, the switching elements Q1p, Q2p, Q3p, Q4p, and Q8p may be controlled in the same manner as in the second embodiment or the third embodiment described above.

  In the above-described ninth embodiment, when the control device 50 executes the reverse power flow control, an example in which the switching elements Q1n, Q2n, Q3n, Q4n, and Q7p are controlled as in the above-described fifth embodiment has been described. However, instead of this, the switching elements Q1n, Q2n, Q3n, Q4n, and Q7p may be controlled in the same manner as in the sixth embodiment described above.

(10th Embodiment)
In the above-described ninth embodiment, as shown in FIG. 39, the example in which the inverter circuit is configured by the bridge circuit 20Y and the switching elements Q7 and Q8 has been described. An inverter circuit may be configured by the circuit 20Y and the switching elements Q5, Q6, Q7, and Q8.

  A three-phase AC motor control device 6C shown in FIG. 41 is configured by adding switching elements Q5 and Q6 to the three-phase AC motor control device 6B of FIG. 41, the same reference numerals as those in FIG. 39 denote the same components, and a description thereof will be omitted.

  Switching elements Q5 and Q6 are connected in series between the plus electrode and the plus electrode of battery 3. The switching element Q5 is composed of switching elements Q5n and Q5p. Switching elements Q5n and Q5p have emitter terminals and collector terminals arranged in opposite directions.

  The switching element Q6 is composed of switching elements Q6n and Q6p. Switching elements Q6n and Q6p have emitter terminals and collector terminals arranged in opposite directions.

  In the present embodiment, the common connection terminal T1 between the switching elements Q7 and Q8 is connected to the first electrode 110a of the stator coil 110 of the three-phase AC motor 100.

  The relay SW2 is connected between the common connection terminal T2 between the switching elements Q5 and Q6 and the second electrode 110b of the stator coil 110. The relay SW2 connects or opens between the common connection terminal T2 and the second electrode 110b of the stator coil 110.

  The relay SW3 is connected between the common connection terminal T3 between the switching elements Q1 and Q4 and the third electrode 110c of the stator coil 110. The relay SW3 connects or opens the common connection terminal T3 and the third electrode 110c of the stator coil 110.

  The relay SW4 is a switch disposed between the common connection terminal T3 between the switching elements Q1 and Q3 and the positive electrode of the battery 3, and connects between the common connection terminal T3 and the positive electrode of the battery 3. Or open.

  The relay SW5 is a switch disposed between the common connection terminal T4 between the switching elements Q1 and Q4 and the reactor 30, and connects or opens between the common connection terminal T4 and the reactor 30.

  As in the ninth embodiment, the control device 50 controls the relays SW1 to SW5 and executes any one of motor control, charge control, and reverse power flow control.

  The control device 50 performs motor control when the relays SW2, SW3, and SW4 are turned on and the relays SW1 and SW5 are turned off.

  The motor control is performed by switching the switching elements Q1p, Q4p, Q5n, Q6n, Q7, Q8 in a state where the switching elements Q3p, Q3n are turned off and the switching elements Q2p, Q2n are turned on, so that the common connection terminals T1, T2 , An alternating current is output to the stator coil 110 from T3. In this case, the switching elements Q1n, Q4n, Q5p, and Q6p serve as rectifier diodes.

  The control device 50 performs charge control or reverse power flow control when the relays SW1, SW5 are turned on and the relays SW2, SW3, SW4 are turned off.

  When executing the charge control, the control device 50 turns off the switching elements Q1n, Q2n, Q3n, Q4n, Q6n, Q7, Q8 and turns on the switching elements Q5p, Q6p, respectively. Similarly to the embodiment, the switching elements Q1p, Q2p, Q3p, Q4p, and Q5n are controlled. The switching element Q5n in FIG. 41 corresponds to the switching element Q5 in FIG. 1, the switching element Q6p in FIG. 41 corresponds to the diode D1 in FIG. 1, and the switching element Q5p in FIG. Corresponds to the diode D2.

  When executing the reverse power flow control, the control device 50 turns off the switching elements Q1p, Q2p, Q3p, Q4p, Q5n, Q7p, Q8p and turns on the switching elements Q5p, Q6p, respectively. As in the embodiment, the switching elements Q1n, Q2n, Q3n, Q4n, and Q6n are controlled. Switching element Q6n in FIG. 41 corresponds to switching element Q6 in FIG.

1 power converter,
2 AC power supply 3 DC load 4 Battery 5 AC load 6A Three-phase AC motor controller 6B Three-phase AC motor controller 6C Three-phase AC motor controller 10 Low-pass filter 20 Bridge circuit 20A Bridge circuit 20B Bridge circuit 20C Bridge circuit 20X bridge circuit 20Y bridge circuit 30 reactor Q1p switching element Q2p switching element Q3p switching element Q4p switching element Q5 switching element Q1n switching element Q2n switching element Q3n switching element Q4n switching element Q5n switching element D40 diode switching element D50 diode switching element D50 Device 51 Voltage sensor 52 Voltage sensor 53 Current sensor

Claims (17)

A bridge circuit (20) which is arranged between the AC power source (2) and the DC load (3) and is configured by first to fourth switching elements (Q1p, Q2p, Q3p, Q4p);
A reactor (30) disposed between the bridge circuit and the positive electrode of the DC load;
A current limiting element (D1) disposed between the reactor and the positive electrode of the DC load to limit the flow of current from the positive electrode side of the DC load to the reactor side;
A fifth switching element (Q5) disposed between the common connection terminal between the reactor and the current limiting element and the negative electrode of the DC load;
Charge control means (S131, S133) for controlling the first to fifth switching elements,
The first switching element (Q1p) is disposed between the positive electrode of the AC power source and the reactor,
The second switching element (Q2p) is disposed between the negative electrode of the AC power source and the negative electrode of the DC load,
The third switching element (Q3p) is disposed between the positive electrode of the AC power source and the negative electrode of the DC load,
The fourth switching element (Q4p) is disposed between the negative electrode of the AC power supply and the reactor,
The charge control means (S133) turns on the first and third switching elements (Q1p, Q3p) in the first charge control period, and turns on the second and fifth switching elements (Q2p, Q5p). To turn the fourth switching element (Q4p) on and off repeatedly,
When the first and third switching elements are turned on and the second and fifth switching elements are turned off and the fourth switching element is turned on, current is supplied from the negative electrode of the AC power source to the fourth The switching element, the reactor, the current limiting element, the DC load, and the third switching element are passed through the positive electrode of the AC power source to store energy in the reactor,
Based on the energy stored in the reactor when the first and third switching elements are turned on and the second and fifth switching elements are turned off and the fourth switching element is turned off, 1. Current is passed through the third switching element, the current limiting element, and the DC load.
Further, the charge control means (S131) turns on the second and fourth switching elements (Q2p, Q4p) in the second charge control period, and the third and fifth switching elements (Q3p, Q5p). ) To turn the first switching element (Q1p) on and off repeatedly,
When the second and fourth switching elements are turned on and the third and fifth switching elements are turned off and the first switching element is turned on, current is supplied from the positive electrode of the AC power source to the reactor, Storing the energy in the reactor by flowing the negative switching electrode of the AC power source through the second and first switching elements, the current limiting element, and the DC load;
Based on the energy stored in the reactor when the second and fourth switching elements are turned on and the third and fifth switching elements are turned off and the first switching element is turned off. 2. A power conversion device characterized in that a current flows through the fourth switching element, the current limiting element, and the DC load. First voltage detecting means (51) for detecting a voltage between the positive electrode and the negative electrode of the AC power source;
When the detection voltage of the first voltage detection means is a negative voltage, the charge control means (S133) turns on the first and third switching elements (Q1p, Q3p), and the second, The fifth switching element (Q2p, Q5p) is turned off and the fourth switching element (Q4p) is repeatedly turned on / off,
When the detection voltage of the first voltage detection means is a positive voltage, the charge control means (S131) turns on the second and fourth switching elements (Q2p, Q4p), and the third, The power conversion device according to claim 1, wherein the fifth switching element (Q3p, Q5p) is turned off to repeatedly turn on and off the first switching element (Q1p). Second voltage detection means (52) for detecting a voltage between the positive electrode and the negative electrode of the DC load;
The charging control means controls the first to fifth switching elements based on the detection voltages of the first and second voltage detection means, thereby allowing the bridge circuit (20) from the AC power supply (2). and sinusoidal variation of the current value with respect to the time axis current (Iac) flowing to), and according to claim 2, characterized in that close to zero phase difference between the output voltage and the current of the AC power source Power converter. A bridge circuit (20) which is arranged between the AC power source (2) and the DC load (3) and is configured by first to fourth switching elements (Q1p, Q2p, Q3p, Q4p);
A reactor (30) disposed between the bridge circuit and the positive electrode of the DC load;
A current limiting element (D1) disposed between the reactor and the positive electrode of the DC load to limit the flow of current from the positive electrode side of the DC load to the reactor side;
A fifth switching element (Q5) disposed between the common connection terminal between the reactor and the current limiting element and the negative electrode of the DC load ;
Charge control means (S150, S151) for controlling the first to fifth switching elements,
The first switching element (Q1p) is disposed between the positive electrode of the AC power source and the reactor,
The second switching element (Q2p) is disposed between the negative electrode of the AC power source and the negative electrode of the DC load,
The third switching element (Q3p) is disposed between the positive electrode of the AC power source and the negative electrode of the DC load,
The fourth switching element (Q4p) is disposed between the negative electrode of the AC power supply and the reactor,
The charge control means (S150, S151) turns on the second and fourth switching elements (Q2p, Q4p) and turns on one of the first and third switching elements (Q1p, Q3p). It is turned off and the other switching element is synchronized with the fifth switching element (Q5) and repeatedly turned on and off,
When the second and fourth switching elements are turned on, the third switching element is turned off and the first and fifth switching elements are turned on, the first, A current is passed through the second and fifth switching elements and the reactor to store energy in the reactor;
When the second and fourth switching elements are turned on and the first, third and fifth switching elements are turned off, the second and fourth switching elements are based on the energy stored in the reactor. Current flows through the element, the current limiting element, and the DC load;
When the second and fourth switching elements are turned on, the first switching element is turned off and the third switching element and the fifth switching element are turned on, the two electrodes of the AC power supply are A power conversion device, wherein current is passed through the third, fourth, and fifth switching elements and the reactor to store energy in the reactor . First voltage detecting means (51) for detecting a voltage between the positive electrode and the negative electrode of the AC power source;
When the detection voltage of the first voltage detection means is a positive voltage, the charge control means (S150) turns on the second and fourth switching elements (Q2p, Q4p) and performs the third switching. The element (Q3p) is turned off, and the first switching element (Q1p) and the fifth switching element (Q5p) are synchronously turned on and off,
When the detection voltage of the first voltage detection means is a negative voltage, the charge control means (S151) turns on the second and fourth switching elements (Q2p, Q4p) and performs the first switching The element (Q1p) is turned off, and the third switching element (Q3p) and the fifth switching element (Q5p) are synchronized and repeatedly turned on and off. Power conversion device. A bridge circuit (20) which is arranged between the AC power source (2) and the DC load (3) and is configured by first to fourth switching elements (Q1p, Q2p, Q3p, Q4p);
A reactor (30) disposed between the bridge circuit and the positive electrode of the DC load;
A current limiting element (D1) disposed between the reactor and the positive electrode of the DC load to limit the flow of current from the positive electrode side of the DC load to the reactor side;
A fifth switching element (Q5) disposed between the common connection terminal between the reactor and the current limiting element and the negative electrode of the DC load ;
Charge control means (S150, S151) for controlling the first to fifth switching elements,
The first switching element (Q1p) is disposed between the positive electrode of the AC power source and the reactor,
The second switching element (Q2p) is disposed between the negative electrode of the AC power source and the negative electrode of the DC load,
The third switching element (Q3p) is disposed between the positive electrode of the AC power source and the negative electrode of the DC load,
The fourth switching element (Q4p) is disposed between the negative electrode of the AC power supply and the reactor,
The charge control means (S150) turns on the second and fourth switching elements, turns off the third switching element, and repeats the first and fifth switching elements in the first charge control period. It is to turn on and off,
When the second and fourth switching elements are turned on, the third switching element is turned off and the first and fifth switching elements are turned on, the first, A current is passed through the second and fifth switching elements and the reactor to store energy in the reactor;
When the second and fourth switching elements are turned on and the first, third and fifth switching elements are turned off, the second and fourth switching elements are based on the energy stored in the reactor. Current flows through the element, the current limiting element, and the DC load;
When the second, fourth, and fifth switching elements are turned on and the first and third switching elements are turned off, the second, fourth, and second switching elements are based on the energy stored in the reactor. Current flows through 5 switching elements,
The charge control means (S151) repeatedly turns on the second and fourth switching elements, turns off the first switching element, and repeats the third and fifth switching elements in the second charge control period. It is to turn on and off,
When the second and fourth switching elements are turned on, the first switching element is turned off and the third and fifth switching elements are turned on, the third, A current is passed through the fourth and fifth switching elements and the reactor to store energy in the reactor;
When the second and fourth switching elements are turned on and the first, third and fifth switching elements are turned off, the second and fourth switching elements are based on the energy stored in the reactor. Current flows through the element, the current limiting element, and the DC load;
When the second, fourth, and fifth switching elements are turned on and the first and third switching elements are turned off, the second, fourth, and second switching elements are based on the energy stored in the reactor. A power conversion device characterized in that a current flows through 5 switching elements . First voltage detecting means (51) for detecting a voltage between the positive electrode and the negative electrode of the AC power source;
When the detection voltage of the first voltage detecting means is a positive voltage, the charge control means (S150) turns on the second and fourth switching elements and turns off the third switching element. The first and fifth switching elements are repeatedly turned on and off,
When the detection voltage of the first voltage detection means is a negative voltage, the charge control means (S151) turns on the second and fourth switching elements and turns off the first switching element. The power converter according to claim 6 , wherein the third and fifth switching elements are repeatedly turned on and off . A bridge circuit (20) which is arranged between the AC power source (2) and the DC load (3) and is configured by first to fourth switching elements (Q1p, Q2p, Q3p, Q4p);
A reactor (30) disposed between the bridge circuit and the positive electrode of the DC load;
A current limiting element (D1) disposed between the reactor and the positive electrode of the DC load to limit the flow of current from the positive electrode side of the DC load to the reactor side;
A fifth switching element (Q5) disposed between the common connection terminal between the reactor and the current limiting element and the negative electrode of the DC load ;
Charge control means (S130, S131, S132, S133, S150, S151) for controlling the first to fifth switching elements;
The first switching element (Q1p) is disposed between the positive electrode of the AC power source and the reactor,
The second switching element (Q2p) is disposed between the negative electrode of the AC power source and the negative electrode of the DC load,
The third switching element (Q3p) is disposed between the positive electrode of the AC power source and the negative electrode of the DC load,
The fourth switching element (Q4p) is disposed between the negative electrode of the AC power supply and the reactor,
The charge control means (S150) turns on the second and fourth switching elements (Q2p, Q4p) and turns off the third switching element (Q3p) during the first charge control time. The fifth switching element (Q1p, Q5p) is repeatedly turned on / off,
When the second and fourth switching elements are turned on and the third switching element is turned off and the first and fifth switching elements are turned on, the first and second switching elements are connected between both electrodes of the AC power supply. 2, current is passed through the fifth switching element and the reactor to store energy in the reactor;
When the second and fourth switching elements are turned on and the third switching element is turned off and the first and fifth switching elements are turned off, the second and fourth switching elements are turned on based on the energy stored in the reactor. Current is passed through the fourth switching element, the current limiting element, and the DC load;
The charge control means (S151) turns on the first and third switching elements (Q1p, Q3p) and turns off the second switching element (Q2p) during the second charge control time, and turns off the fourth switching element (Q2p). The fifth switching element (Q4p, Q5p) is repeatedly turned on / off,
When the first and third switching elements are turned on, the second switching element is turned off and the fourth and fifth switching elements are turned on, the reactor between the electrodes of the AC power supply, and A current is passed through the third, fourth and fifth switching elements to store energy in the reactor;
When the first and third switching elements are turned on and the second, fourth and fifth switching elements are turned off, the first and third switching elements are based on the energy stored in the reactor. A power conversion device characterized in that a current flows through the current limiting element and the DC load . First voltage detecting means (51) for detecting a voltage between the positive electrode and the negative electrode of the AC power source;
When the detection voltage of the first voltage detection means is a positive voltage, the charge control means (S150) turns on the second and fourth switching elements (Q2p, Q4p) and turns on the third switching element. (Q3p) is turned off, and the first and fifth switching elements (Q1p, Q5p) are repeatedly turned on / off,
When the detection voltage of the first voltage detection means is a negative voltage, the charge control means (S151) turns on the first and third switching elements (Q1p, Q3p) and turns on the second switching element. 9. The power conversion device according to claim 8 , wherein (Q2p) is turned off and the fourth and fifth switching elements (Q4p, Q5p) are repeatedly turned on and off . Second voltage detection means (52) for detecting a voltage between the positive electrode and the negative electrode of the DC load;
The charging control means controls the first to fifth switching elements based on the detection voltages of the first and second voltage detection means, thereby allowing the bridge circuit (20) from the AC power supply (2). and sinusoidal variation of the current value with respect to the time axis current (Iac) flowing to), and wherein the closer to zero the phase difference between the output voltage and the current of the alternating current power supply according to claim 5 and 7 , 9. The power conversion device according to any one of 9 . A power converter (1) according to any one of claims 1 to 10 ,
Seventh and eighth switching elements (Q7, Q8) connected in series between the positive electrode and the negative electrode of the DC load (3) of the power converter,
Of the seventh and eighth switching elements (Q7, Q8), the seventh switching element (Q7) on the positive electrode side of the DC load constitutes the current limiting element,
Of the seventh and eighth switching elements (Q7, Q8), the eighth switching element (Q8) on the negative electrode side of the DC load constitutes the fifth switching element (Q5),
The common connection terminal (T1) between the seventh and eighth switching elements and the first electrode (110a) of the stator coil (110) constituting the three-phase AC motor are connected,
A first switch (SW1) for connecting or opening between the bridge circuit of the power converter and the AC power source (2);
A second connection for connecting or opening between the common connection element (T2) between the second and fourth switching elements (Q2p, Q4p) of the power conversion device and the second electrode (110b) of the stator coil. A switch (SW2);
A third connecting or opening between the common connection element (T3) between the first and third switching elements (Q1p, Q3p) of the power converter and the third electrode (110c) of the stator coil. Switch (SW3),
A fourth switch (SW4) disposed between the common connection element (T4) between the first and fourth switching elements and the positive electrode of the DC load;
A fifth switch (SW5) disposed between the common connection element (T4) between the first and fourth switching elements and the reactor;
Switch control means (50) for controlling the first to fifth switches;
When the switch control means turns on the second, third, and fourth switches among the first to fifth switches, the first, second, third, fourth, seventh, and eighth The switching element is controlled so that the common connection terminal (T3) between the first and third switching elements, the common connection terminal (T2) between the second and fourth switching elements, and the seventh And an inverter control means (50) for driving the three-phase AC motor by flowing an AC current from the common connection terminal (T1) of the eighth switching element to the stator coil,
When the switch control unit turns on the first and fifth switches among the first to fifth switches, the charge control unit includes the first to fourth switching elements and the seventh and eighth switches . A control device for an electric motor that controls the switching element of the motor. A bridge circuit (20B) which is arranged between the DC power supply (4) and the AC load (5) and is configured by first to fourth switching elements (Q1n, Q2n, Q3n, Q4n);
A reactor (30) disposed between the bridge circuit and the positive electrode of the DC power source;
A sixth switching element (Q6) disposed between the reactor and the positive electrode of the DC power source;
Arranged between the common connection terminal between the reactor and the sixth switching element (Q6) and the negative electrode of the DC power supply (4), the DC power supply (4) from the common connection terminal side. A current limiting element (D2) that prevents current from flowing to the negative electrode side;
Reverse flow control means (131a, 133a) for controlling the first to fourth switching elements and the sixth switching element,
The first switching element (Q1n) is disposed between the positive electrode of the AC load and the reactor,
The second switching element (Q2n) is disposed between the negative electrode of the AC load and the negative electrode of the DC power source,
The third switching element (Q3n) is disposed between the positive electrode of the AC load and the negative electrode of the DC power source,
The fourth switching element (Q4n) is disposed between the negative electrode of the AC load and the reactor,
The reverse flow control means (S 131a ) turns on the first, second, and sixth switching elements (Q1n, Q2n, Q6n) in the first reverse flow control period, and turns on the third switching element ( Q3n) is turned off and the fourth switching element (Q4n) is repeatedly turned on and off,
The second, fourth, and sixth switching elements between the electrodes of the DC power source when the first, second, fourth, and sixth switching elements are turned on and the third switching element is turned off; And passing current through the reactor to store energy in the reactor,
When the first, second, and sixth switching elements are turned on and the third and fourth switching elements are turned off, the first and second switching elements are based on energy stored in the reactor. And passing current through the AC load,
The reverse flow control means ( 133a ) turns on the third, fourth, and sixth switching elements (Q3n, Q4n, Q6n) in the second reverse flow control period, and turns on the second switching element (Q2n). ) To turn the first switching element (Q1n) on and off repeatedly,
When the first, third, fourth, and sixth switching elements are turned on and the second switching element is turned off, the first, third, and sixth switching elements between the electrodes of the DC power supply; And passing current through the reactor to store energy in the reactor,
Based on the energy stored in the reactor when the third, fourth, and sixth switching elements are turned on and the first and second switching elements are turned off, the third, fourth, and second 6. A power converter , wherein a current flows through the switching element 6, the current limiting element, and the AC load . First voltage detection means (51) for detecting the output voltage of the AC load;
When the detection voltage of the first voltage detection means is a positive voltage, the reverse flow control means (S 131a ) turns on the first, second, and sixth switching elements (Q1n, Q2n, Q6n). Then, the third switching element (Q3n) is turned off and the fourth switching element (Q4n) is repeatedly turned on / off,
When the detection voltage of the first voltage detection means is a negative voltage, the reverse flow control means ( 133a ) turns on the third, fourth, and sixth switching elements (Q3n, Q4n, Q6n). Te, the power converter according to claim 12, characterized in der Rukoto one which the second and turns off the switching element (Q2n) of the first switching element (Q1n) repeatedly turned on and off. A bridge circuit (20B) which is arranged between the DC power supply (4) and the AC load (5) and is configured by first to fourth switching elements (Q1n, Q2n, Q3n, Q4n);
A reactor (30) disposed between the bridge circuit and the positive electrode of the DC power source;
A sixth switching element (Q6) disposed between the reactor and the positive electrode of the DC power source;
Arranged between the common connection terminal between the reactor and the sixth switching element (Q6) and the negative electrode of the DC power supply (4), the DC power supply (4) from the common connection terminal side. A current limiting element (D2) that prevents current from flowing to the negative electrode side;
Reverse flow control means (150b, 151b) for controlling the first to fourth switching elements and the sixth switching element,
The first switching element (Q1n) is disposed between the positive electrode of the AC load and the reactor,
The second switching element (Q2n) is disposed between the negative electrode of the AC load and the negative electrode of the DC power source,
The third switching element (Q3n) is disposed between the positive electrode of the AC load and the negative electrode of the DC power source,
The fourth switching element (Q4n) is disposed between the negative electrode of the AC load and the reactor,
The reverse flow control means (S150b) turns on the first and second switching elements (Q1n, Q2n) and turns off the third switching element (Q3n) in the first reverse flow control period. The fourth and sixth switching elements (Q4n, Q6n) are repeatedly turned on / off,
The second, fourth, and sixth switching elements between the electrodes of the DC power source when the first, second, fourth, and sixth switching elements are turned on and the third switching element is turned off; And passing current through the reactor to store energy in the reactor,
When the first and second switching elements are turned on and the third, fourth and sixth switching elements are turned off, the first and second switching elements are based on the energy stored in the reactor. Current is passed through the current limiting element and the AC load,
The reverse flow control means (S151b) turns on the third and fourth switching elements (Q3n, Q4n) and turns off the first switching element (Q1n) in the second reverse flow control period. The second and sixth switching elements (Q4n, Q6n) are repeatedly turned on / off,
When the second, third, fourth, and sixth switching elements are turned on and the first switching element is turned off, the second, fourth, and sixth switching elements between the electrodes of the DC power supply; And passing current through the reactor to store energy in the reactor,
Based on the energy stored in the reactor when the third and fourth switching elements are turned on and the first, second and sixth switching elements are turned off, the third and fourth A power conversion device , wherein a current flows through a switching element, the current limiting element, and the AC load . First voltage detecting means (51) for detecting an output voltage of the AC load;
When the detection voltage of the first voltage detection means is a positive voltage, the reverse flow control means (S150b) turns on the first and second switching elements (Q1n, Q2n), and the third The switching element (Q3n) is turned off, and the fourth and sixth switching elements (Q4n, Q6n) are repeatedly turned on / off,
When the detection voltage of the first voltage detection means is a negative voltage, the reverse power flow control means (S151b) turns on the third and fourth switching elements (Q3n, Q4n) and turns on the first the second off the switching element (Q1n), a sixth switching element (Q4n, Q6n) power converter according to claim 14, characterized in der Rukoto one which repeatedly turned on and off. Second voltage detecting means (52) for detecting the output voltage of the DC power supply;
The reverse power flow control means controls the first to fourth and sixth switching elements based on the detection voltages of the first and second voltage detection means, thereby causing the bridge circuit (20) to The change of the current value with respect to the time axis of the current (Iac) flowing through the AC load (5) is made sinusoidal, and the phase difference between the voltage between the electrodes of the AC load and the current is brought close to zero. The power converter according to claim 13 or 15 , wherein A power converter (1) according to any one of claims 12 to 16,
Seventh and eighth switching elements (Q7, Q8) connected in series between the positive electrode and the negative electrode of the DC power source (3) of the power converter,
Of the seventh and eighth switching elements (Q7, Q8), the eighth switching element (Q8) on the negative electrode side of the DC power supply constitutes the current limiting element,
Of the seventh and eighth switching elements (Q7, Q8), the seventh switching element (Q7) on the positive electrode side of the DC power supply constitutes the sixth switching element (Q6),
The common connection terminal (T1) between the seventh and eighth switching elements and the first electrode (110a) of the stator coil (110) constituting the three-phase AC motor are connected,
A first switch (SW1) for connecting or opening between the bridge circuit of the power converter and the AC load (5);
A second connection for connecting or opening between the common connection element (T2) between the second and fourth switching elements (Q2n, Q4n) of the power conversion device and the second electrode (110b) of the stator coil. A switch (SW2);
A third connecting or opening between the common connection element (T3) between the first and third switching elements (Q1n, Q3n) of the power converter and the third electrode (110c) of the stator coil. Switch (SW3),
A fourth switch (SW4) disposed between the common connection element (T4) between the first and fourth switching elements and the positive electrode of the DC load;
A fifth switch (SW5) disposed between the common connection element (T4) between the first and fourth switching elements and the reactor;
Switch control means (50) for controlling the first to fifth switches;
When the switch control means turns on the second, third, and fourth switches among the first to fifth switches, the first, second, third, fourth, seventh, and eighth The switching element is controlled so that the common connection terminal (T3) between the first and third switching elements, the common connection terminal (T2) between the second and fourth switching elements, and the seventh And an inverter control means (50) for driving an alternating current from a common connection terminal (T1) between the eighth switching elements to the stator coil to drive the three-phase alternating current motor,
When the switch control means turns on the first and fifth switches among the first to fifth switches, the reverse power flow control means controls the first to fourth and seventh switching elements. A control device for an electric motor.

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