JP5477644B2 - Power converter - Google Patents

Description

  The present invention relates to a power conversion device including at least a capacitor, a switching element, a drive circuit, a drive power supply, and the like.

  In the conventional power converter, when discharging the electric charge accumulated in the smoothing capacitor, all the switching elements are turned on, and one or more switching elements are turned off before the current flowing through the switching elements becomes overcurrent. Is disclosed (see, for example, Patent Document 1). In addition, a technique is disclosed in which the control voltage of the switching element is controlled by current limiting means when the output of the DC voltage from the main power supply is turned off (see, for example, Patent Document 2).

JP 2009-232620 A Japanese Patent Laid-Open No. 9-201065

  In the above-described conventional power conversion device, the charge stored in the smoothing capacitor can be discharged by controlling the driving of the switching element. However, when the power supply to the driving circuit that performs the driving control is cut off, the switching element There is a problem in that it cannot be driven and cannot be discharged. As a measure for solving this problem, a drive circuit that operates at the time of discharging (that is, a timing at which the charge accumulated in the capacitor is discharged) is provided separately from the drive circuit that operates at a normal time (that is, when the power conversion is performed). In addition, the two drive circuits may be configured to supply power from separate power sources.

  However, when two drive circuits are connected in parallel and the drive of the switching element is controlled by a drive signal output individually from the two drive circuits, the drive circuit is driven from one drive circuit to the other drive circuit through the connection point. The signal may wrap around. If the drive signal wraps around, the other drive circuit may malfunction.

  The present invention has been made in view of the above points, and prevents a driving signal from wrapping around from one driving circuit to the other driving circuit, so that the switching element can be reliably connected both during normal operation and during discharging. It aims at providing the power converter device which can perform drive control.

  The invention according to claim 1, which has been made to solve the above problem, is a capacitor that is connected to both ends of the output side of the power supply source and smoothes, and a switching device that converts the power supplied from the power supply source and outputs the converted power. In a power conversion device comprising: an element; a normal driving circuit that drives the switching element when converting the power; and a normal driving power source that operates the normal driving circuit, the charge accumulated in the capacitor The discharge driving circuit for driving the switching element and the normal driving power source are provided separately from each other, and the discharging driving power source for operating the discharging driving circuit is provided. Interposed between the power supply for power supply and the switching element and between the power supply for driving during discharge and the switching element, and the normal-time drive circuit and the discharge element. And having a wraparound preventing means for preventing the driving signal to be Mawarikomo toward the one of the drive circuit to the other drive circuit of the time of driving circuit.

  According to this configuration, the sneak preventing means is interposed between the normal driving power source and the switching element and between the discharging driving power source and the switching element. The drive signal is surely prevented from sneaking up. Accordingly, the drive control of the switching element can be surely performed both during normal times and during discharge.

  Note that “normal time” means a time or period during which normal power conversion is performed, and “during discharge” means a time or period during which the charge accumulated in the capacitor is discharged without performing power conversion. Therefore, the normal time and the discharge time do not coincide with each other. As the “switching element”, any semiconductor element having a switching function can be used, for example, an IGBT or a power transistor. As the “capacitor”, any circuit element capable of accumulating and discharging (discharging) electric charges in order to realize a smoothing function can be used, and includes a storage / discharge means such as a capacitor. The “normal driving circuit” needs to be provided for each switching element. The “discharge driving circuit” and the “wraparound prevention means” may be provided corresponding to each of one or more switching elements driven during discharge.

  The invention described in claim 2 is characterized in that the wraparound prevention means is included in the normal driving circuit and the discharging driving circuit. According to this configuration, even if the normal drive circuit and the discharge drive circuit are connected in parallel, the drive circuit is included in both of the drive circuits, so that the drive circuit rotates from one drive circuit to the other drive circuit. It is possible to block the driving signal to be included. Therefore, the drive control of the switching element can be surely performed both during normal times and during discharge, and the wiring can be simplified and the circuit components can be easily assembled.

  The invention described in claim 3 is characterized in that a rectifying element (rectifier) is applied to the wraparound prevention means. According to this configuration, it is possible to prevent the driving signal from wrapping around with a simple configuration, and to reduce the cost.

  According to a fourth aspect of the present invention, a switching element is applied to the wraparound prevention means. According to this configuration, it is possible to reduce the influence of a voltage drop during conduction (when the switching element is on). In addition, since it is possible to control the on / off state of the switching element during normal times and during discharge, it is possible to reliably prevent the driving signal from wrapping around.

  The invention described in claim 5 is characterized in that a MOS transistor is used as the switching element. According to this configuration, when a PMOS transistor (that is, a P-channel MOS transistor) is used, the influence of a voltage drop during conduction (when the MOS transistor is turned on) can be suppressed to a minimum, and the area can be reduced. Can do. When an NMOS transistor (that is, an N-channel MOS transistor) is used, switching between on and off can be performed at high speed.

  The invention according to claim 6 is characterized in that when the MOS transistor is a PMOS transistor, a malfunction prevention means for preventing malfunction of the PMOS transistor is provided between the gate terminal and the source terminal of the PMOS transistor. To do. According to this configuration, the PMOS transistor is prevented from malfunctioning due to malfunction factors such as noise. Therefore, even if noise or the like occurs, it is possible to reliably prevent the driving signal from wrapping around.

  According to a seventh aspect of the present invention, each of the normal driving circuit and the discharging driving circuit includes a voltage generation unit that generates a voltage necessary for driving the switching element, and the wraparound prevention unit includes the voltage It is characterized by being interposed between the generation unit and the driving power supply corresponding to each driving circuit. According to this configuration, a voltage necessary for driving the switching element is generated by the voltage generating unit, and the sneak preventing means is interposed between the voltage generating unit (more specifically, the feedback terminal) and the driving power source. Therefore, the voltage generated by the voltage generator is transmitted to the switching element (more specifically, the gate terminal) without causing a voltage drop. Therefore, it is possible to reliably prevent the drive signal from being sneak in and to reliably drive the switching element both during normal operation and during discharge.

  The invention according to claim 8 is characterized in that the discharge-time drive circuit does not drive the switching element when an off-control unit that turns off the switching element is operated by the normal-time drive circuit. To do. The off control unit forcibly turns off the switching element when the voltage value of the power supplied from the power source falls below a reference value (for example, 10 [V]) until the off control falls below an operable threshold. continue. According to this configuration, after the voltage value of the power supplied from the power source falls below the threshold, the discharging drive circuit outputs a drive signal. Therefore, it is possible to prevent the drive signal from wrapping around during the operation of the off control unit.

  According to a ninth aspect of the present invention, each of the normal driving circuit and the discharging driving circuit includes an off control unit that turns off the switching element, and includes a malfunction prevention unit that prevents malfunction of the off control unit. It is characterized by that. According to this configuration, the off control unit is prevented from malfunctioning due to malfunction factors such as noise. Therefore, even when noise or the like occurs, the control by the off control unit can be performed reliably.

  The invention described in claim 10 is characterized in that one or both of circuit elements of a resistor and a capacitor are applied to the malfunction prevention means. According to this configuration, malfunction can be prevented with a simple configuration, so that the cost can be kept low.

  In the invention according to claim 11, the sneak preventing means interposed between the normal driving power source and the switching element can be controlled from both the normal driving circuit and the discharging driving circuit, The wraparound prevention means interposed between the discharge driving power source and the switching element can be controlled from both the normal driving circuit and the discharging drive circuit. According to this configuration, even when the normal driving power supply does not function during normal operation or when the discharging driving power supply does not function during discharging, the drive circuit is driven by the power supplied from the remaining driving power supply, Activate the wraparound prevention means. Therefore, it is possible to prevent the situation where the sneak preventing means is not activated and to prevent the driving signal from sneaking.

It is a figure which shows typically the structural example of a power converter device. It is a figure which shows the example which implement | achieves a wraparound prevention means with a switch. It is a figure which shows the example which implement | achieves a wraparound prevention means with a rectifier. It is a figure which shows the example which implement | achieves a wraparound prevention means with a transistor. It is a figure which shows the 1st structural example which makes a drive voltage intrinsic | native to a drive circuit. It is a figure which shows the 2nd structural example which makes a drive voltage intrinsic | native to a drive circuit. It is a figure which shows the example which makes a wraparound prevention means inherent in the ON side circuit of a drive circuit. It is a figure which shows the example which makes a wraparound prevention means inherent in the off side circuit of a drive circuit. It is a figure which shows an example provided with a malfunction prevention means in a wraparound prevention means. It is a figure which shows the example provided with a voltage detection circuit in a drive circuit. It is a figure which shows the example applied to an inverter circuit. It is a figure which shows the example of application to a converter circuit.

  Below, the form for implementing this invention is demonstrated based on drawing. Unless otherwise specified, “connect” means electrical connection. Further, the continuous code is simplified using the symbol “˜”. For example, “switching elements Q1 to Q6” means “switching elements Q1, Q2, Q3, Q4, Q5, Q6”. When referring to directions such as up, down, left and right, the description in the drawings is used as a reference.

[Embodiment 1]
In the first embodiment, various configuration examples will be described with reference to FIGS. First, FIG. 1 schematically shows a configuration example of a power conversion device in a block diagram. More specifically, FIG. 1A shows an example in which a wraparound prevention means is interposed between each drive circuit and the switching element. FIG. 1B shows an example in which the wraparound prevention means is included in the drive circuit.

  1A includes a normal drive circuit 1, a discharge drive circuit 2, a sneak preventing means 3, a normal drive power supply 4, a discharge drive power supply 5, a controller 6, a switching element Qa, A diode Da is included. Among these elements, the normal driving circuit 1 needs to be provided corresponding to each switching element Qa. On the other hand, the discharge driving circuit 2 and the sneak preventing means 3 are one or more switching elements that are driven at the time of discharging (a time other than the normal time and discharging the charge accumulated in the capacitor Ca). What is necessary is just to provide for every Qa. About another element, what is necessary is just to provide one or more in a power converter device.

  The switch Sw has a function of switching power reception (on) / non-power reception (off) for power supplied from the power supply source Es. As the switch Sw, it is desirable to use an element that can be switched on / off from the controller 6 or the like. At the time of discharging, the electric charge accumulated in the capacitor Ca is discharged. However, if power is continuously supplied from the power supply source Es, the capacitor Ca cannot be discharged. Therefore, the switch Sw is switched to non-power receiving (off) at the time of discharging, so that the charge accumulated in the capacitor Ca can be discharged.

  The capacitor Ca is provided in one or both of the power conversion device and the power supply source Es, and has a function of connecting and smoothing to both ends on the output side of the power supply source Es. Any element can be used as long as it can store and discharge (release) electric charges. For example, a capacitor may be used.

  The normal-time drive circuit 1 sends a drive signal to the control terminal (gate terminal) of the switching element Qa based on a command signal input from the controller 6 to the signal input terminal Pa in normal time (time when normal power conversion is performed). To control ON / OFF of the switching element Qa. The normal driving circuit 1 operates by receiving electric power (voltage Va) supplied from the normal driving power source 4. The driving signal may be any signal that can drive the switching element, and corresponds to, for example, a pulse width modulation signal.

  The discharge driving circuit 2 outputs a driving signal to the control terminal (gate terminal) of the switching element Qa at the time of discharging (time other than normal time and discharging of the electric charge accumulated in the capacitor Ca). The on / off of the switching element Qa is controlled. The drive signal is output based on the command signal input from the controller 6 to the signal input terminal Pb, and the discharge drive circuit 2 is based on its own judgment (hereinafter referred to as “active configuration”). )) Or both. The active configuration corresponds to, for example, a seventh configuration example or an eighth configuration example described later. That is, the power (voltage Va) supplied to the normal driving circuit 1 is monitored, and when the power (voltage Va) changes from the normal value and reaches a predetermined threshold (for example, 3 [V], etc.), A drive signal is output to the switching element Qa. The discharge driving circuit 2 operates by receiving electric power (voltage Vb) supplied from the discharge driving power source 5.

  The wraparound prevention means 3 wraps around from one drive circuit (for example, the normal time drive circuit 1) to the other drive circuit (for example, the discharge time drive circuit 2) of the normal time drive circuit 1 and the discharge time drive circuit 2. A function to block the driving signal is realized. The wraparound prevention means 3 is connected to be interposed between the normal driving circuit 1 and the switching element Qa and between the discharging driving circuit 2 and the switching element Qa. A specific configuration example of the wraparound prevention means 3 will be described later (see FIGS. 2 to 10).

  The switching element Qa has a function of converting and outputting power supplied from the power supply source Es. As the switching element Qa, an arbitrary semiconductor element having a switching function such as an IGBT or a power transistor is used. The diode Da is connected in parallel between the input terminal (source terminal) and the output terminal (emitter terminal) of the switching element Qa, and both function as a freewheeling diode. As shown in FIG. 1A, one switching element Qa may be connected, or two or more (plural) switching elements Qa may be connected in cascade (see FIGS. 10 and 11 described later).

  The normal driving power source 4 and the discharging driving power source 5 are separate power sources, so that even if one of the power sources stops functioning and power is cut off, power can be supplied from the other power source. Configured. The controller 6 is a control device that controls the operation (on / off) of switching elements included in the power conversion device and other devices / circuits and performs other controls.

  The power conversion device shown in FIG. 1 (B) has substantially the same configuration as the power conversion device shown in FIG. 1 (A), but the arrangement of the wraparound prevention means 3 is different. That is, in FIG. 1 (A), each drive circuit and the switching element Qa are interposed and connected, whereas in FIG. 1 (B), they are included in each drive circuit. Specifically, the sneaking prevention means 3 a is included in the normal driving circuit 1, and the sneaking prevention means 3 b is included in the normal driving circuit 1. The sneaking prevention means 3 shown in FIG. 1A and the sneaking prevention means 3a and the sneaking prevention means 3b shown in FIG. 1B have the same configuration. In other words, the wraparound prevention means 3 is configured as a part of each drive circuit. Therefore, the operation and effect of the power converter are the same.

  Below, the specific structural example of the wraparound prevention means 3 is demonstrated, referring FIGS. Note that the same elements as those shown in FIG.

(First configuration example)
First, the wraparound prevention means 3 shown in FIGS. 2A and 2B includes switches S3a and S3b. The switches S3a and S3b are arbitrary as long as they are electronic components having a function of switching on / off of the connection state by the controller 6 (or other control device or the like). For example, contact switches, electromagnetic switches (including relays), semiconductor switches, and the like are applicable. The switch S3a is connected to be interposed between the normal driving circuit 1 and the switching element Qa, and the switch S3b is connected to be connected between the discharging driving circuit 2 and the switching element Qa. The operations of the switch S3a and the switch S3b are controlled so that the on and off states are reversed.

  For example, in the normal state, as shown in FIG. 2A, the switch S3a is turned on and the switch S3b is turned off. Therefore, when the driving signal is output from the normal driving circuit 1 to the control terminal of the switching element Qa, the driving signal does not flow into the discharging driving circuit 2 because the switch S3b is OFF. On the other hand, at the time of discharging, as shown in FIG. 2B, the switch S3a is turned off and the switch S3b is turned on. Therefore, when the driving signal is output from the driving circuit 2 during discharging to the control terminal of the switching element Qa, the driving signal does not flow into the normal driving circuit 1 because the switch S3a is OFF.

  Although not shown, the above-described switches S3a and S3b shown in FIGS. 2A and 2C may be included as part of each drive circuit. That is, the switch S3a is included on the output terminal side of the normal driving circuit 1, and the switch S3b is included on the output terminal side of the discharging drive circuit 2. Even if it is set as this structure, the effect similar to the case where it is set as a different structure can be acquired.

  The wraparound prevention means 3 shown in FIG. 2C includes a switch S3c and the like. The switch S3c is optional as long as it is a so-called three-point switch, as long as it is an electronic component having a function of switching the connection state by the controller 6 (or other control device or the like) in the same manner as the switches S3a and S3b described above. is there.

  For example, at the normal time, the switch S3c is switched to the normal driving circuit 1 side as indicated by a solid line. Therefore, when the driving signal is output from the normal driving circuit 1 to the control terminal of the switching element Qa, the driving signal does not circulate into the discharging driving circuit 2. On the other hand, at the time of discharging, as shown by the broken line, the switch S3c is switched to the driving circuit 2 side at the time of discharging. Therefore, when a driving signal is output from the discharging driving circuit 2 to the control terminal of the switching element Qa, the driving signal does not circulate into the normal driving circuit 1.

(Second configuration example)
3 includes diodes D3a and D3b. The diodes D3a and D3b are optional as long as they are rectifying elements (or rectifiers) that have a rectifying action. Both of the diodes D3a and D3b are connected to the corresponding drive circuit on the anode (anode) side, and connected to the switching element Qa on the cathode (cathode) side. Therefore, even if the driving signal flows toward the switching element Qa, the driving signal is prevented from flowing toward the driving circuit, so that the driving signal is prevented from wrapping around.

  Although not shown, the above-described diodes D3a and D3b shown in FIG. 3 may be included as part of each drive circuit. The diode D3a is included on the output terminal side of the normal driving circuit 1, and the diode D3b is included on the output terminal side of the discharging driving circuit 2. Even if it is set as this structure, the effect similar to the case where it is set as a different structure can be acquired.

(Third configuration example)
4 includes capacitors C3a and C3b and resistors R3a and R3b as malfunction preventing means together with the switching elements Q3a and Q3b. The switching elements Q3a and Q3b are arbitrary as long as they are semiconductor elements capable of switching between conduction and non-conduction of wirings and lines. For example, a MOS transistor such as a PMOS transistor or an NMOS transistor can be applied. The control terminals (gate terminals) of the switching elements Q3a and Q3b are connected to the signal output terminals Sa1 and Sb1 of the corresponding drive circuits, respectively. By this connection, switching of the switching elements Q3a and Q3b is controlled individually according to the control signals output from the signal output terminals Sa1 and Sb1. That is, the operation of the switching element Q3a and the switching element Q3b is controlled in cooperation so that the on and off states are opposite to each other.

  The switching element Q3a is connected between the normal driving circuit 1 and the switching element Qa. More specifically, the signal output terminal Sa2 of the normal driving circuit 1 and the input terminal (source terminal) of the switching element Q3a are connected, and the output terminal (emitter terminal) of the switching element Q3a and the control terminal of the switching element Qa ( Gate terminal). The switching element Q3b is connected between the driving circuit 2 during discharge and the switching element Qa in the same manner as the switching element Q3a described above.

  Further, a capacitor C3a and a resistor R3a are connected in parallel between the control terminal (gate terminal) and the input terminal (source terminal) of the switching element Q3a. Similarly, a capacitor C3b and a resistor R3b are connected in parallel between the control terminal (gate terminal) and the input terminal (source terminal) of the switching element Q3b. These capacitors C3a, C3b and resistors R3a, R3b prevent the switching elements Q3a, Q3b from malfunctioning due to noise or the like, respectively.

  Although not shown, the switching elements Q3a and Q3b shown in FIG. 4 described above may be included as part of each drive circuit. The switching element Q3a (moreover, the capacitor C3a and the resistor R3a) is provided on the output terminal side of the normal driving circuit 1, and the switching element Q3b (further, the capacitor C3b and the resistor R3b) is placed on the output terminal side of the driving circuit 2 during discharging. To be inherent. Even if it is set as this structure, the effect similar to the case where it is set as a different structure can be acquired. Also, MOS transistors (PMOS transistors, NMOS transistors, etc.) may be used instead of the switching elements Q3a, Q3b.

(Fourth configuration example)
The wraparound preventing means 3 shown in FIG. 5 is inherent in the drive circuit and includes switches S3a, S3b and the like. The switch S3a is inherent in the normal driving circuit 1, and the switch S3b is inherent in the discharging driving circuit 2. The signal output terminal Sa1 and the signal input terminal Sa3 of the normal drive circuit 1 and the signal output terminal Sb1 and the signal input terminal Sb3 of the discharge drive circuit 2 are both connected to the control terminal (gate terminal) of the switching element Qa. The The ground terminal San of the normal drive circuit 1 and the ground terminal Sbn of the discharge drive circuit 2 are connected to the output terminal (emitter terminal) of the switching element Qa. Hereinafter, examples of internal configurations of the normal driving circuit 1 and the discharging driving circuit 2 will be briefly described. The drive voltage generation circuits 1a and 2a each correspond to a “voltage generation unit”, and the off-side circuits 1c and 2c each correspond to an “off control unit”.

  The normal drive circuit 1 includes a drive voltage generation circuit 1a, an on-side circuit 1b, an off-side circuit 1c, and resistors R1a and R1b in addition to the switch S3a described above. The drive voltage generation circuit 1a receives the power (voltage Va) supplied from the normal driving power supply 4 and generates and outputs power for driving the switching element Qa through the on-side circuit 1b. The on-side circuit 1b has a function of outputting a driving signal for operating the switching element Qa from the signal output terminal Sa2 at the normal time. The off-side circuit 1c has a function of discharging from the signal input terminal Sa3 through the grounding terminal San during gate discharge or normal off driving. The resistors R1a and R1b connected in series are connected between the input terminal of the on-side circuit 1b and the ground terminal San. An output terminal of the drive voltage generation circuit 1a is connected to a connection point between the resistor R1a and the resistor R1b. Therefore, a feedback loop is formed between the input terminal of the on-side circuit 1b and the ground terminal San via the resistors R1a and R1b.

  The switch S3a is connected between an input terminal of power supplied from the normal driving power supply 4 and an input terminal of the on-side circuit 1b. When the switch S3a is on (when conducting), the on-side circuit 1b receives power supplied from the normal driving power supply 4. When the switch S3a is off (during non-conduction), the on-side circuit 1b receives power generated by the drive voltage generation circuit 1a. That is, the power supply source is switched according to the on / off state of the switch S3a. In particular, at the time of discharging, the switch S3a is turned off, and even if the driving signal flows to the on-side circuit 1b through the off-side circuit 1c, it is greatly attenuated by the resistors R1a and R1b and can be ignored.

  In addition to the switch S3b described above, the discharging drive circuit 2 includes a drive voltage generation circuit 2a, an on-side circuit 2b, an off-side circuit 2c, resistors R2a and R2b, and the like. The drive voltage generation circuit 2a has the same function as the drive voltage generation circuit 1a described above except that it receives power (voltage Vb) supplied from the drive power supply 5 at the time of discharge. The on-side circuit 2b has the same function as the above-described on-side circuit 1b, and the off-side circuit 2c has the same function as the above-described off-side circuit 1c. The connection between the switch S3b and the resistors R2a and R2b is the same as that of the switch S3a and the resistors R1a and R1b described above. Therefore, a feedback loop is formed between the input terminal of the on-side circuit 2b and the ground terminal Sbn via the resistors R2a and R2b. Further, the power supply source is switched according to the on / off state of the switch S3b. Normally, the switch S3b is turned off, and even if the drive signal flows to the on-side circuit 2b through the off-side circuit 2c, it is greatly attenuated by the resistors R2a and R2b and can be ignored.

  In FIG. 5, the normal driving circuit 1 has a separate drive voltage generating circuit 1 a and an on-side circuit 1 b, and the discharging driving circuit 2 includes the driving voltage generating circuit 2 a and the on-side circuit 2 b. It was set as the separate body structure provided separately. Instead of this configuration, a configuration (integrated configuration) that serves as both the drive voltage generation circuit 1a and the on-side circuit 1b, or a configuration that serves as both the drive voltage generation circuit 2a and the on-side circuit 2b (integrated configuration) may be employed. For example, FIG. 6 shows a configuration example in which the drive voltage generation circuit 1a is provided in the on-side circuit 1b and the drive voltage generation circuit 2a is provided in the on-side circuit 2b. Although not shown in the drawings, the drive voltage generation circuit 1a may include the on-side circuit 1b, or the drive voltage generation circuit 2a may include the on-side circuit 2b. Similarly, a combination of the normal driving circuit 1 shown in FIG. 5 and the discharging driving circuit 2 shown in FIG. 6 or a combination of the discharging driving circuit 2 shown in FIG. 5 and the normal driving circuit 1 shown in FIG. For example, a separate configuration and an integrated configuration may be mixed.

(Fifth configuration example)
The wraparound prevention means 3 shown in FIG. 7 is inherent in the drive circuit and includes switching elements Q1b, Q2b and the like. The switching element Q1b is inherent in the normal driving circuit 1, and the switching element Q2b is inherent in the discharging driving circuit 2. Hereinafter, examples of internal configurations of the normal driving circuit 1 and the discharging driving circuit 2 will be briefly described.

  The switching element Q1b that constitutes the on-side circuit 1b of the normal driving circuit 1 has an original function of receiving a power (voltage Va) supplied from the normal driving power supply 4 and outputting a driving signal for the switching element Qa. It is a function and doubles as a wraparound prevention function. That is, the switching element Q1b performs on / off switching in the normal state based on a command signal input from the controller 6 to the signal input terminal Pb, and outputs the driving signal described above. In order to prevent the driving signal from entering from 2, the signal is turned off.

  The switching element Q2b that constitutes the on-side circuit 2b of the driving circuit 2 at the time of discharge has an original function of receiving a power (voltage Vb) supplied from the driving power source 5 at the time of discharging and outputting a driving signal for the switching element Qa. It is a function and doubles as a wraparound prevention function. That is, the switching element Q1b is turned off in order to prevent a drive signal from going around from the normal driving circuit 1 based on a command signal input from the controller 6 to the signal input terminal Pb. At that time, the above-mentioned driving signal is output by switching on / off.

(Sixth configuration example)
The wraparound prevention means 3 shown in FIG. 8 is inherent in the drive circuit and includes switching elements Q1c, Q2c and the like. Specifically, the switching element Q1c is inherent in the normal driving circuit 1, and the switching element Q2c is inherent in the discharging driving circuit 2. For example, NMOS transistors (N-channel type MOS transistors) are used as the switching elements Q1c and Q2c. Hereinafter, examples of internal configurations of the normal driving circuit 1 and the discharging driving circuit 2 will be briefly described. Since it is similar to the fifth configuration example shown in FIG. 7, differences will be mainly described. Further, since the sixth configuration example is configured to prevent the driving signal from wrapping around the off-side circuits 1c and 2c, the on-side circuits 1b and 2b are configured to prevent the driving signal from spilling separately. It is desirable to configure (see, for example, FIGS. 5 and 6).

  The switching element Q1c constituting the off-side circuit 1c of the normal driving circuit 1 has an input terminal (source terminal) connected to a control terminal (gate terminal) of the switching element Qa via a signal input terminal Sa3, and an output terminal (drain) Terminal) is connected to the output terminal (emitter terminal) of the switching element Qa via the ground terminal San. A resistor R1c is connected between the control terminal (gate terminal) and the output terminal (drain terminal) of the switching element Q1c. The switching element Q1c normally operates based on a command signal input from the controller 6 to the signal input terminal Pa, and is turned on (conducting) or off (non-conducting), and is off (non-conducting) during discharging. ) State. The resistor R1c prevents the switching element Q1c from malfunctioning when the power supply from the normal driving power supply 4 is cut off.

  The switching element Q2c constituting the off-side circuit 2c of the discharging driving circuit 2 operates based on a command signal input from the controller 6 to the signal input terminal Pb during discharging, and is in an on (conducting) state or off (non-conducting). In a normal state, it is turned off (non-conductive). The connection form and operation of the switching element Q2c are the same as those of the switching element Q1c described above. The resistor R2c prevents the switching element Q2c from malfunctioning when the supply of power from the driving power supply 5 during discharge is cut off.

  In the configuration example shown in FIG. 8, NMOS transistors capable of switching on / off at high speed are used as the switching elements Q1c and Q2c, but other semiconductor elements capable of switching conduction / non-conduction of wirings and lines are used. Also good. For example, a PMOS transistor (P-channel MOS transistor), an NPN transistor, a PNP transistor, or the like can be used.

(Seventh configuration example)
The wraparound prevention means 3 shown in FIG. 9 has the same configuration as the third configuration example (see FIG. 4). The difference from the third configuration example shown in FIG. 4 is the connection point between the power supply path 4 supplied from the normal driving power supply 4 and the discharging drive power supply 5 and the ground terminals San and Sbn. With respect to the power path, the power of the normal driving power supply 4 is connected so as to be supplied to both the normal driving circuit 1 and the discharging driving circuit 2, and the power of the discharging driving power supply 5 is connected to the normal driving circuit 1 and It connects so that it can supply to both the drive circuits 2 at the time of discharge. Further, the grounding terminal San of the normal driving circuit 1 is connected to the signal output terminal Sb1 of the discharging driving circuit 2, and the grounding terminal Sbn of the discharging driving circuit 2 is connected to the signal output terminal Sa1 of the normal driving circuit 1. To do.

  According to the configuration described above, even if the supply of power from one of the normal driving power supply 4 and the discharging driving power supply 5 is interrupted due to some factor, the supply of power from the other power supply is continued. Even in this state, it is possible to reliably switch on / off the switching elements Q3a and Q3b between the normal time and the discharge time, and to prevent the drive signal from going around. Further, when the discharge driving circuit 2 has an active configuration, even when the controller 6 stops operating and does not receive a command signal, a driving signal is output to the control terminal (gate terminal) of the switching element Qa, The on / off state of the switching element Qa can be controlled.

  In the configuration example shown in FIG. 9, the third configuration example shown in FIG. 4 is applied, but other configuration examples (that is, the first configuration example, the second configuration example, and the fourth configuration example to the sixth configuration example) are applied. May be. Even when these configuration examples are applied, the supply of power from the other power source is continued, and a drive signal that is going to sneak in between the normal time and the discharge time can be prevented.

(Eighth configuration example)
The wraparound prevention means 3 shown in FIG. 10 has the same configuration as the first configuration example (see FIG. 2). The difference from the first configuration example shown in FIG. 4 is that the normal driving circuit 1 includes a voltage detection circuit 1v, and the discharging driving circuit 2 includes a voltage detection circuit 2v. The voltage detection circuit 1v detects the voltage value of the power supplied from the driving power supply 5 at the time of discharge, and the voltage detection circuit 2v detects the voltage value of the power supplied from the normal-time driving power supply 4.

  When the voltage value of the power supplied from the normal driving power supply 4 falls below a reference value (for example, 10 [V]) for some reason, the normal driving circuit 1 turns off the switching element Qa forcibly. It has a function. The off function works until it drops below a voltage value at which the drive circuit 1 can operate normally (hereinafter referred to as “threshold”; for example, 3 [V]). If the driving signal is output from the discharge driving circuit 2 for discharging while the OFF function is operating, the driving signal may circulate into the normal driving circuit 1. Therefore, the voltage detection circuit 2v detects the voltage value of the power supplied from the normal driving power supply 4, and after the voltage value falls below the threshold value, the discharging driving circuit 2 outputs a driving signal for discharging. To be configured. According to this configuration, even when the power supplied from the discharge driving power supply 5 is cut off, the drive signal is output from the discharge drive circuit 2 after the voltage value falls below the threshold value. It is possible to prevent the drive signal from wraparound due to the off function on the hour drive circuit 1 side acting.

  The discharge drive circuit 2 is configured in the same manner as the normal drive circuit 1 described above except that the detection target of the voltage detection circuit 2v is power supplied from the discharge drive power supply 5. According to this configuration, even when the power supplied from the normal driving power supply 4 is cut off, the driving signal is output from the discharging driving circuit 2 after the voltage value has dropped below the threshold value. It is possible to prevent the drive signal from wrapping around due to the off function on the hour drive circuit 2 side acting. Further, when the discharge driving circuit 2 has an active configuration, it is possible to control the on / off of the switching element Qa even when the controller 6 does not operate and receives a command signal as in the seventh configuration example. it can.

  In the configuration example shown in FIG. 10, the first configuration example shown in FIG. 2 is applied, but other configuration examples (that is, the second configuration example to the sixth configuration example) may be applied. Even when these configuration examples are applied, it is possible to prevent the drive signal from wrapping around due to the off function of the drive circuit acting.

  According to the first embodiment described above, the following effects can be obtained. First, corresponding to claim 1, when discharging the electric charge accumulated in the capacitor Ca, the discharge driving circuit 2 for driving the switching element Qa by receiving the electric power supplied from the capacitor Ca, and the normal driving power source 4 Are provided separately from each other, and are operated between the discharge driving power source 5 for operating the discharge driving circuit 2, between the normal driving power source 4 and the switching element Qa, and between the discharging driving power source 5 and the switching element Qa. And a sneak preventing means 3 for blocking a driving signal from one driving circuit of the normal driving circuit 1 and the discharging driving circuit 2 toward the other driving circuit. Provided (see FIG. 1A). According to this configuration, the sneak preventing means 3 is interposed between the normal driving power source 4 and the switching element Qa and between the discharging driving power source 5 and the switching element Qa. Thus, it is possible to reliably prevent the drive signal from sneaking into the other drive circuit. Therefore, the drive control of the switching element Qa can be reliably performed both during normal times and during discharge.

  Corresponding to claim 2, the wraparound prevention means 3 is configured to be included in the normal driving circuit 1 and the discharging driving circuit 2 (see FIG. 1B). According to this configuration, even if the normal drive circuit 1 and the discharge drive circuit 2 are connected in parallel, the wraparound prevention means 3 is inherent in both of the drive circuits, and therefore, from one drive circuit to the other drive circuit. It is possible to block the drive signal that tries to wrap around. Therefore, the drive control of the switching element Qa can be surely performed both during normal times and during discharge, and the wiring can be simplified and the circuit components can be easily assembled.

  Corresponding to claim 3, the wraparound prevention means 3 is configured using diodes D3a and D3b (rectifying elements) (see FIG. 3). According to this configuration, it is possible to prevent the driving signal from wrapping around with a simple configuration, and to reduce the cost.

  Corresponding to claim 4, the wraparound prevention means 3 is configured using switching elements Q3a and Q3b (see FIG. 4). According to this configuration, it is possible to suppress the influence of a voltage drop when the switching elements Q3a and Q3b are turned on. Further, since the on / off of the switching elements Q3a and Q3b can be controlled during normal time and during discharging, it is possible to reliably prevent the driving signal from wrapping around.

  Corresponding to claim 5, a MOS transistor is used as the switching element (see FIGS. 4 and 8). In the case of using a PMOS transistor, the influence of a voltage drop during conduction (when the MOS transistor is on) can be suppressed to a minimum, and can be realized with a minimum area. When using an NMOS transistor, switching between ON and OFF can be performed at high speed.

  Corresponding to claim 6, when the MOS transistor is a PMOS transistor, one of resistors R3a and R3b and capacitors C3a and C3b or between the control terminal (gate terminal) and the input terminal (source terminal) of the PMOS transistor It was set as the structure provided with both (malfunction prevention means) (refer FIG. 4, FIG. 9). According to this configuration, even if noise or the like occurs, the switching elements Q3a and Q3b (PMOS transistors) can be prevented from malfunctioning, and the drive signal can be reliably prevented from wrapping around.

  Corresponding to claim 7, the normal-time drive circuit 1 and the discharge-time drive circuit 2 are each configured to include drive voltage generation circuits 1a and 2a (voltage generation units) that generate voltages necessary for driving the switching element Qa. (See FIG. 5). Further, the switches S3a and S3b (around prevention means 3) are configured to be interposed between the drive voltage generation circuits 1a and 2a and the drive power supply corresponding to each drive circuit (see FIG. 5). According to this configuration, the voltage generated by the drive voltage generation circuits 1a and 2a is output to the control terminal (gate terminal) of the switching element Qa without causing a voltage drop. Therefore, it is possible to reliably prevent the driving signal from wrapping around and to reliably drive the switching element Qa both during normal operation and during discharge.

  Corresponding to Claim 8, when the off-side circuits 1c and 2c (off control unit) in which the normal driving circuit 1 turns off the switching element Qa are operating, the discharging driving circuit 2 operates the switching element Qa. It was set as the structure which is not driven (refer FIG. 10). According to this configuration, after the voltage value of the power supplied from the normal driving power supply 4 falls below the threshold value, the discharging driving circuit 2 outputs a driving signal. Therefore, it is possible to prevent the driving signal from wrapping around during the operation of the off-side circuit 1c.

  Corresponding to claim 9, the normal drive circuit 1 and the discharge drive circuit 2 are respectively an off-side circuit 1c, 2c (off control unit) for turning off the switching element Qa and an off-side circuit 1c, 2c (specifically Is provided with resistors R1c, R2c (malfunction prevention means) for preventing malfunction of the switching elements Q1c, Q2c) (see FIG. 8). According to this configuration, even when noise or the like occurs, the control by the off-side circuits 1c and 2c can be reliably performed.

  Corresponding to claim 10, the malfunction prevention means uses one or both of the circuit elements of resistors R3a and R3b and capacitors C3a and C3b (see FIGS. 4 and 9). According to this configuration, malfunction can be prevented with a simple configuration, so that the cost can be kept low.

  Corresponding to claim 11, the switching element Q3a (wraparound prevention means 3) interposed between the normal driving power source 4 and the switching element Qa is controlled from both the normal driving circuit 1 and the discharging driving circuit 2. (See FIG. 9). Further, the switching element Q3b (wraparound prevention means 3) interposed between the discharge driving power source 5 and the switching element Qa is controlled by both the normal driving circuit 1 and the discharging driving circuit 2. (See FIG. 9). According to this configuration, even when the normal driving power source 4 is cut off during normal times or when the discharging driving power source 5 is cut off during discharging, the drive circuit is driven by the power supplied from the remaining driving power source. By driving, switching elements Q3a and Q3b can be operated reliably. Therefore, the situation where switching elements Q3a and Q3b do not operate can be prevented, and the wraparound of the drive signal can be prevented.

[Embodiment 2]
The second embodiment is an example in which each configuration example shown in the first embodiment is applied to an inverter circuit, and will be described with reference to FIG. For simplicity of illustration and description, the second embodiment will be described with respect to differences from the first embodiment. Therefore, the same elements as those used in Embodiment 1 are denoted by the same reference numerals, and description thereof is omitted.

  In the following description, the inverter circuit 20 corresponds to a “power converter” in relation to the first embodiment. The converter circuit 10 corresponds to “power supply source Es”. The capacitor C2 corresponds to the “capacitor Ca”. Switching elements Q1 to Q6 correspond to “switching element Qa”, respectively. Each of the diodes D1 to D6 corresponds to “diode Da”. The normal driving circuits M1a to M6a correspond to the “normal driving circuit 1”. The discharge driving circuits M1b to M6b correspond to the “discharge driving circuit 2”, respectively. Any of the first configuration example to the eighth configuration example may be applied to the normal driving circuit M1a, the discharging driving circuit M1b, and the wraparound prevention means B1. Similarly, any of the first configuration example to the eighth configuration example may be applied to the normal driving circuits M2a to M6a, the discharging driving circuits M2b to M6b, and the wraparound prevention means B2 to B6, respectively. The switch Sw is interposed between the converter circuit 10 and the capacitor C2.

  The inverter circuit 20 illustrated in FIG. 11 is configured to be able to realize one or both of a power feeding function and a power transmission function. The power feeding function converts DC power (voltage VH) supplied from the DC power supply E1 through the converter circuit 10 into three-phase AC power and supplies it to the generator motor 30 (an output device capable of both engine starting and power generation). It is a function. The power transmission function is a function of rectifying the three-phase AC power generated by the generator motor 30 and returning it to the DC power source E1 via the converter circuit 10. A smoothing capacitor C1 is connected to the output terminal side of the DC power supply E1, and a smoothing capacitor C2 is connected to the output terminal side of the converter circuit 10. One or both of the switch Sw and the capacitor C2 may be included in the inverter circuit 20.

  The inverter circuit 20 includes normal driving circuits M1a to M6a, discharging driving circuits M1b to M6b, sneaking prevention means B1 to B6, switching elements Q1 to Q6, diodes D1 to D6, resistors R1 to R6, and the like. Among these, the normal driving circuits M1a to M3a, the discharging driving circuits M1b to M3b, the sneak prevention means B1 to B3, the switching elements Q1 to Q3, the diodes D1 to D3, the resistors R1 to R3, etc. are arranged on the upper arm side. Is done. The normal driving circuits M4a to M6a, the discharging driving circuits M4b to M6b, the sneak prevention means B4 to B6, the switching elements Q4 to Q6, the diodes D4 to D6, and the resistors R4 to R6 are arranged on the lower arm side. The discharge driving circuits M1b to M6b and the wraparound prevention means B1 to B6 may each include one or more. The configuration example of FIG. 11 includes only U-phase driving circuits M1b and M4b and wraparound prevention means B1 and B4 as shown by the solid line. As another configuration example relating to the discharge driving circuit and the wraparound prevention means, only the V phase, only the W phase, two phases (for example, the U phase and the V phase) to be selected, or all three phases may be provided. .

  The normal driving circuits M1a to M6a correspond to the “normal driving circuit 1”. The normal driving circuits M1a to M3a operate by receiving electric power (voltage Va) supplied from the normal driving power supply 4 with the output terminals (emitter terminals) of the switching elements Q1 to Q3 as reference potentials. The normal driving circuits M4a to M6a operate by receiving power (voltage Vc) supplied from the normal driving power supply 4 with the output terminals (emitter terminals) of the switching elements Q4 to Q6 as the reference potential. These normal-time drive circuits M1a to M6a send drive signals to the control terminals (gate terminals) of the corresponding switching elements Q1 to Q6 according to command signals individually input from the controller 6 to the signal input terminals P1a to P6a. Output.

  The discharge driving circuits M1b to M6b correspond to the “discharge driving circuit 2”, respectively. The discharge drive circuits M1b to M3b operate by receiving power (voltage Vb) supplied from the discharge drive power supply 5 with the output terminals (emitter terminals) of the switching elements Q1 to Q3 as reference potentials. The discharge driving circuits M4b to M6b operate by receiving electric power (voltage Vd) supplied from the discharge driving power supply 5 using the output terminals (emitter terminals) of the switching elements Q4 to Q3 as reference potentials. These discharge driving circuits M1b to M6b send driving signals to the control terminals (gate terminals) of the corresponding switching elements Q1 to Q6 in accordance with command signals individually input from the controller 6 to the signal input terminals P1b to P6b. Output.

  One normal driving power supply 4 may be provided (see FIG. 11), or a plurality of normal driving power supplies 4 may be provided for each normal driving circuit M1a to M6a. The same applies to the driving power source 5 at the time of discharging, and one embodiment may be provided (see FIG. 11), or a plurality may be provided corresponding to each of the discharging driving circuits M1b to M6b. Note that the voltages Va, Vb, Vc, and Vd described above are not limited to the same voltage but may be different depending on the difference in the reference potential.

  As the switching elements Q1 to Q6, for example, an IGBT including sense terminals Ps1 to Ps6 that output a sense current is used. Resistors R4 to R6 are connected between the sense terminals Ps4 to Ps6 and the base potential N, respectively. Resistors R1 to R3 are connected to output terminals (emitter terminals) of corresponding switching elements Q1 to Q3, respectively. The base potential N is a common potential (same potential ground) in the inverter circuit 20 and becomes 0 [V] when grounded.

  The circuit elements in the inverter circuit 20 are divided into three phases (in this embodiment, U phase, V phase, W phase) as surrounded by a two-dot chain line, and the operation is controlled for each phase by the controller 6. The U phase includes normal driving circuits M1a and M4a, discharging driving circuits M1b and M4b, switching elements Q1 and Q4, diodes D1 and D4, resistors R1 and R4, and the like. The V phase includes normal driving circuits M2a and M5a, discharging driving circuits M2b and M5b, switching elements Q2 and Q5, diodes D2 and D5, resistors R2 and R5, and the like. The W phase includes normal driving circuits M3a and M6a, discharging driving circuits M3b and M6b, switching elements Q3 and Q6, diodes D3 and D6, resistors R3 and R6, and the like. The U-phase switching elements Q1 and Q4 are connected in series to form a half bridge. Similarly, the V-phase switching elements Q2 and Q5 and the W-phase switching elements Q3 and Q6 are connected in series to form a half bridge. Each connection point of the half bridge and the three-phase terminal of the generator motor 30 are connected for each phase by lines Ku, Kv, Kw. A U-phase current Iu flows through the line Ku, a V-phase current Iv flows through the line Kv, and a W-phase current Iw flows through the line Kw.

  The controller 6 controls the entire operation of the converter circuit 10, the inverter circuit 20, and the like. That is, based on the input signal information, command signals are individually output to the normal driving circuits M1a to M6a and the discharging driving circuits M1b to M6b included in the converter circuit 10. Signal information includes signals transmitted from an external ECU (including an external control device equivalent to this) (for example, torque commands), state detection information (for example, sense voltage, temperature, gate voltage, terminal voltage, etc.), A detection signal transmitted from a detector (for example, a voltmeter, an ammeter, a resolver, etc.) provided in the generator motor 30 is applicable. Further, signal information is output to the external ECU, and an operation signal is output to the detector.

  As long as each function described above is performed, the controller 6 may be arbitrarily configured. For example, a software control may be performed by a CPU (including a microcomputer), or a hardware control may be performed using an electronic component such as an IC (including an LSI or a gate array) or a transistor.

  The inverter circuit 20 configured as described above operates as follows. Under normal conditions, driving signals from the normal driving circuits M1a to M6a are driven to the control terminals (gate terminals) of the switching elements Q1 to Q6 based on command signals individually input from the controller 6 to the signal input terminals P1a to P6a. The signal is transmitted, and the electric power supplied from the converter circuit 10 is converted and output to the generator motor 30. Further, at the time of discharging, a driving signal is driven to the control terminals (gate terminals) of the switching elements Q1 to Q6 from the discharging driving circuits M1b to M6b based on command signals individually input from the controller 6 to the signal input terminals P1b to P6b. The signal for use is transmitted, and the electric charge accumulated in the capacitor C2 is discharged. Since the wraparound prevention means B1 to B6 are interposed, it is possible to prevent the drive signal from wrapping from one drive circuit to the other drive circuit among the normal drive circuits M1a to M6a and the discharge drive circuits M1b to M6b. .

  Since the inverter circuit 20 shown in the second embodiment described above applies the normal driving circuit 1, the discharging driving circuit 2 and the wraparound preventing means 3 shown in the first embodiment, the same effects as those of the first embodiment are obtained. Can be obtained.

[Embodiment 3]
The third embodiment is an example in which each configuration example shown in the first embodiment is applied to a converter circuit, and will be described with reference to FIG. For simplicity of illustration and description, the second embodiment will be described with respect to differences from the first embodiment. Therefore, the same elements as those used in Embodiment 1 are denoted by the same reference numerals, and description thereof is omitted.

  In the following description, the converter circuit 10 corresponds to a “power converter” in relation to the first embodiment. The DC power supply E1 corresponds to “power supply source Es”. The capacitor C1 corresponds to the “capacitor Ca”. The switching elements Qu and Qd correspond to “switching element Qa”, respectively. Each of the diodes Du and Dd corresponds to “diode Da”. The normal driving circuits Mua and Mda correspond to the “normal driving circuit 1”. The discharge drive circuits Mub and Mdb correspond to the “discharge drive circuit 2”, respectively. Any of the first configuration example to the eighth configuration example may be applied to the normal driving circuit Mua, the discharging driving circuit Mub, and the wraparound prevention means Bu. Similarly, any of the first configuration example to the eighth configuration example may be applied to the discharging drive circuit Mub, the discharging drive circuit Mdb, and the wraparound prevention means Bd. The switch Sw is interposed between the DC power supply E1 and the capacitor C1.

  The converter circuit 10 shown in FIG. 12 realizes a boost function that boosts and outputs the power (voltage VL) supplied from the DC power supply E1, so that the normal-time drive circuits Mua and Mda, the discharge-time drive circuits Mub and Mdb, It has switching elements Qu and Qd, diodes Du and Dd, an inductor L10, and the like.

  The normal driving circuits Mua and Mda correspond to the “normal driving circuit 1”. The normal driving circuit Mua operates by receiving power (voltage Va) supplied from the normal driving power supply 4 with the output terminal (emitter terminal) of the switching element Qu as a reference potential. The normal drive circuit Mda operates by receiving power (voltage Vc) supplied from the normal drive power supply 4 with the output terminal (emitter terminal) of the switching element Qd as a reference potential. These normal-time drive circuits Mua and Mda respectively send drive signals to the control terminals (gate terminals) of the corresponding switching elements Qu and Qd in accordance with command signals individually input from the controller 6 to the signal input terminals Pua and Pda. Output.

  The discharge drive circuits Mub and Mdb correspond to the “discharge drive circuit 2”, respectively. The discharge driving circuit Mub and the output terminal (emitter terminal) of the switching element Qu are operated with reference to the power (voltage Vb) supplied from the driving power source 5 for discharging. The discharge drive circuit Mdb operates by receiving power (voltage Vd) supplied from the discharge drive power supply 5 with the output terminal (emitter terminal) of the switching element Qd as a reference potential. These discharge-time drive circuits Mub and Mdb respectively send drive signals to the control terminals (gate terminals) of the corresponding switching elements Qu and Qd according to command signals individually input from the controller 6 to the signal input terminals Pub and Pdb. Output. Note that the voltages Va, Vb, Vc, and Vd described above are not limited to the same voltage but may be different depending on the difference in the reference potential.

  Each of the wraparound prevention means Bu and Bd corresponds to the “wraparound prevention means 3”. The wraparound prevention means Bu is interposed between and connected to the normal driving circuit Mua and the switching element Qu and between the discharging driving circuit Mub and the switching element Qu. The wraparound prevention means Bd is connected between the normal driving circuit Mda and the switching element Qd and between the discharging driving circuit Mdb and the switching element Qd. Any of the first to eighth configuration examples shown in the first embodiment may be applied to these wraparound prevention means Bu and Bd.

  The switching elements Qu and Qd are connected in series to form a half bridge. As the switching elements Qu and Qd, for example, an IGBT including sense terminals Psu and Psd for outputting a sense current is used. A resistor Rd is connected between the sense terminal Psd and the base potential N. The resistor Ru is connected between the sense terminal Psu and an intermediate connection point between the input terminal (such as a source terminal or a collector terminal) of the switching element Qd. This intermediate connection point is further connected to the plus electrode of the DC power supply E1 via the inductor L10. For this inductor L10, for example, a choke coil is used. The diodes Du and Dd connected in parallel to the switching elements Qu and Qd function as freewheel diodes, respectively. The output terminal (emitter terminal) of the switching element Qd is connected to the negative electrode (that is, the base potential N) of the DC power supply E1.

  Other than the converter circuit 10, there are a switch Sw, capacitors C1 and C2, and the like. The switch Sw has a function of switching power reception (on) / non-power reception (off) for the power supplied from the DC power supply E1. The switch Sw is preferably connected between the DC power source E1 and the capacitor C1, and is preferably an element that can be switched on / off from the controller 6 or the like. The smoothing capacitor C1 is connected to both ends (between the plus electrode and the minus electrode) of the DC power supply E1. The smoothing capacitor C <b> 2 is connected to both ends of the output side of the converter circuit 10. One or both of the switch Sw and the capacitor C1 may be included in the converter circuit 10.

  The converter circuit 10 configured as described above operates as follows. At normal times, based on command signals individually input from the controller 6 to the signal input terminals Pua and Pda, driving signals from the normal driving circuits Mua and Mda are used for driving the control terminals (gate terminals) of the switching elements Qu and Qd. The signal is transmitted, and the power supplied from the DC power supply E1 is converted (boosted) and output. Further, at the time of discharging, a driving signal is driven from the driving circuit Mub, Mdb at the time of discharge to the control terminals (gate terminals) of the switching elements Qu, Qd based on command signals individually input from the controller 6 to the signal input terminals Pub, Pdb. The signal for use is transmitted, and the electric charge accumulated in the capacitor C1 is discharged. Since the wraparound prevention means Bu and Bd are interposed, it is possible to prevent the drive signal from wrapping from one drive circuit to the other drive circuit among the normal drive circuits Mua and Mda and the discharge drive circuits Mub and Mdb. .

  The converter circuit 10 shown in the above-described third embodiment employs the normal driving circuit 1, the discharging driving circuit 2 and the sneak preventing means 3 shown in the first embodiment, so that the same effects as the first embodiment are obtained. Can be obtained.

[Other Embodiments]
Although the form for implementing this invention was demonstrated according to Embodiment 1-3 in the above, this invention is not limited to the said form at all. In other words, various forms can be implemented without departing from the scope of the present invention. For example, the following forms may be realized.

  The second embodiment described above is applied to the inverter circuit 20, and the third embodiment is applied to the converter circuit 10. Instead of this form, another circuit or device including at least the normal driving circuit 1 and the switching element Qa shown in FIG. 1 and including the wraparound prevention means 3 together with the discharging driving circuit 2 that operates at the time of discharging. It is possible to apply similarly. Even with such other circuits and devices, the same effects as those of the first to third embodiments can be obtained.

  In Embodiment 3 mentioned above, the three-phase generator motor 30 was applied as an output apparatus (refer FIG. 11). Instead of this form, generator motors other than three phases, or other output devices operable by receiving power output from the inverter circuit 20 regardless of the number of phases may be applied. Examples of other output devices include one or more of a rotating machine (that is, a generator, a motor, and the like), a power system, a load, and the like. Even generator motors other than three-phase and other output devices can be operated by the inverter circuit 20, so that the same effects as those of the first to third embodiments can be obtained.

  In Embodiments 1 to 3 described above, IGBTs having sense terminals are applied as switching elements Qa, Q1 to Q6, Qu, and Qd for power conversion (see FIGS. 1 to 12). Instead of this form, another semiconductor element having a switching function may be applied. Other semiconductor elements include IGBTs without sense terminals, power MOSFETs, and the like. Since the types of switching elements are merely different, the same operational effects as those of the first to third embodiments can be obtained.

  In the first to third embodiments, MOS transistors are applied as the switching elements Q3a and Q3b and the switching elements Q1c and Q2c, which are components of the wraparound prevention means 3 (see FIGS. 4, 8, and 9). Instead of this form, other semiconductor elements capable of switching between conduction / non-conduction of wirings and lines may be applied. Other semiconductor elements include transistors other than MOS transistors, diodes, varistors, thyristors, and the like. Since the types of the semiconductor elements are merely different, the same effects as those of the first to third embodiments can be obtained.

Es Power supply source Ca capacitor (storage / discharge means)
DESCRIPTION OF SYMBOLS 1 Normal time drive circuit 1a, 2a Drive voltage generation circuit 1b, 2b ON side circuit 1c, 2c OFF side circuit 1v, 2v Voltage detection circuit 2 Discharge time drive circuit 3 Rounding prevention means 4 Normal time drive power supply 5 Discharge time drive Power supply 6 Controller Qa Switching element Da Diode 10 Converter circuit (Power converter)
20 Inverter circuit (power converter)
30 Generator motor (output equipment)
E1 DC power supply (power supply source)
C1, C2 capacitors (smoothing capacitors, capacitors)

Claims (11)

A capacitor connected to both ends of the output side of the power supply source for smoothing, a switching element for converting and outputting the power supplied from the power supply source, and a normal time for driving the switching element when converting the power In a power converter comprising: a drive circuit; and a normal driving power source that operates the normal driving circuit.
A discharge driving circuit for driving the switching element when discharging the charge accumulated in the capacitor; and
A power supply for driving at the time of discharge that is provided separately from the power supply for driving at the time of normal operation to operate the driving circuit at the time of discharge;
One of the normal time drive circuit and the discharge time drive circuit is interposed between the normal time drive power source and the switching element and between the discharge time drive power supply and the switching element. A sneak preventing means for blocking a driving signal from the driving circuit to the other driving circuit;
The power converter characterized by having.   The power converter according to claim 1, wherein the wraparound prevention unit is included in the normal driving circuit and the discharging driving circuit.   The power converter according to claim 1, wherein a rectifying element is applied to the wraparound prevention unit.   The power conversion device according to claim 1, wherein a switching element is applied to the wraparound prevention unit.   The power converter according to claim 4, wherein a MOS transistor is used as the switching element.   6. The power conversion according to claim 5, wherein when the MOS transistor is a PMOS transistor, a malfunction prevention means for preventing malfunction of the PMOS transistor is provided between a gate terminal and a source terminal of the PMOS transistor. apparatus. Each of the normal driving circuit and the discharging driving circuit has a voltage generation unit that generates a voltage necessary for driving the switching element,
The power converter according to any one of claims 1 to 6, wherein the wraparound prevention unit is interposed between the voltage generation unit and a driving power source corresponding to each driving circuit.   8. The discharge-time drive circuit does not drive the switching element when an off control unit that turns off the switching element is operated by the normal-time drive circuit. The power conversion device according to one item. The normal driving circuit and the discharging driving circuit each include an off control unit that turns off the switching element,
The power conversion device according to claim 1, further comprising a malfunction prevention unit that prevents malfunction of the off control unit.   10. The power conversion device according to claim 6, wherein one or both of a resistor and a capacitor are applied to the malfunction prevention means. 11. The wraparound prevention means interposed between the normal driving power source and the switching element can be controlled from both the normal driving circuit and the discharging driving circuit.
11. The wraparound prevention means interposed between the discharge driving power source and the switching element can be controlled from both the normal driving circuit and the discharging drive circuit. The power converter device as described in any one of.

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