CN105226977A - A kind of control method of inverter, device and uninterrupted power supply - Google Patents

Abstract

The embodiment of the present invention provides a control method, device and uninterruptible power supply of an inverter including RB-IGBT, which are used to solve the problem of overcurrent in the existing T-type three-level inverter topology using RB-IGBT. , where the RB-IGBT will withstand reverse voltage, resulting in the problem of reverse leakage current. The method includes: determining that an overcurrent occurs in the T-type three-level inverter, and the switch tube on the main bridge arm in the T-type three-level inverter is in a state of receiving a control signal; The switching tube on the main bridge arm in the T-type three-level inverter outputs a control signal; from the moment when the stop outputs the control signal to the switching tube on the main bridge arm in the T-type three-level inverter , after the first preset time length, output a turn-on signal to the switching tube on the auxiliary bridge arm of the T-type three-level inverter that bears the reverse voltage, and the auxiliary bridge in the T-type three-level inverter The switching tube on the arm is RB-IGBT.

Description

Inverter control method, device and uninterruptible power supply

technical field

The invention relates to the technical field of power electronics, in particular to a control method, device and uninterruptible power supply of an inverter including RB-IGBT.

Background technique

The three-level topology has the characteristics of high withstand voltage level and low distortion rate of voltage and current. The traditional three-level structure can be divided into diode-clamped, capacitor-clamped and cascaded. Among them, the diode-clamped structure is simple , widely used, and has received widespread attention. The T-type three-level inverter derived from the diode-clamped topology is more efficient than the diode-clamped topology at low switching frequencies, so it is gradually being widely used in the industry. The traditional T-type three-level inverter topology auxiliary bridge arm uses two power switching devices connected end to end, while the current T-type three-level inverter topology, as shown in Figure 1, the auxiliary bridge arm uses RB-IGBT (reverse Blocking Insulated Gate Bipolar Transistor, ReversingBlockingInsulatedGateBipolarTransistor), that is, switch tube T2 and switch tube T3 are connected in parallel. Due to the particularity of its process and structure, the loss of RB-IGBT is better than that of other manufacturers' power devices of the same power level. The main difference between traditional IGBT and RB-IGBT is the reverse blocking ability of RB-IGBT. Ordinary IGBTs do not have reverse blocking capability. RB-IGBT has the ability to withstand reverse voltage, so no anti-parallel diode is needed.

In the T-type three-level inverter topology shown in FIG. 1 , when an overcurrent occurs, the switching tube T1 , the switching tube T2 , the switching tube T3 and the switching tube T4 are turned off. When a positive overcurrent occurs, that is, the current flows from the output terminal OUT of the T-type three-level inverter topology to the neutral point N (a filter and a load are connected in series between the output terminal OUT and the neutral point N, not shown in Figure 1 When shown), the T-type three-level inverter topology shown in Figure 1 performs freewheeling through the diode D2, so the output terminal OUT is pulled to the negative bus BUS- voltage, and the reverse voltage borne by the switch tube T3 is positive , Half of the difference between the negative bus voltage. When a negative overcurrent occurs, that is, the current flows from the neutral point N of the T-type three-level inverter topology to the output terminal OUT (a filter and a load are connected in series between the output terminal OUT and the neutral point N, not shown in Figure 1 When shown), the T-type three-level inverter topology shown in Fig. 1 conducts freewheeling through the diode D1, therefore, the output terminal OUT is pulled to the positive bus BUS+ voltage, and the reverse voltage borne by the switching tube T2 is positive, Half of the difference in negative bus voltage.

Because the RB-IGBT is under the reverse voltage, there will be a reverse leakage current, and the reverse leakage current will cause the temperature of the RB-IGBT to rise sharply, which may eventually cause the RB-IGBT to overheat and fail, causing great difficulty in its application.

To sum up, when the existing T-type three-level inverter topology using RB-IGBT parallel connection occurs overcurrent, the RB-IGBT will bear the reverse voltage, thereby generating reverse leakage current, which will cause RB -The temperature of the IGBT rises sharply, which may eventually cause the RB-IGBT to overheat and fail.

Contents of the invention

Embodiments of the present invention provide a control method, device and uninterruptible power supply for an inverter including RB-IGBTs, which are used to solve the problem of overcurrent in the existing T-type three-level inverter topology that uses RB-IGBTs in parallel. When, the RB-IGBT will withstand the reverse voltage, which will cause the problem of reverse leakage current.

Based on the above problems, an embodiment of the present invention provides a control method for an inverter including RB-IGBTs, including:

It is determined that an overcurrent occurs in the T-type three-level inverter, and the switching tube on the main bridge arm in the T-type three-level inverter is in a state of receiving a control signal;

stop outputting control signals to the switching tubes on the main bridge arm in the T-shaped three-level inverter;

From the moment when the output of the control signal to the switching tube on the main bridge arm in the T-type three-level inverter is stopped, after a first preset time length, the T-type three-level inverter The switch tube on the auxiliary bridge arm of the inverter that bears the reverse voltage outputs a turn-on signal, and the switch tube on the auxiliary bridge arm in the T-type three-level inverter is an RB-IGBT.

An embodiment of the present invention provides a control device for an inverter including RB-IGBT, including:

A determining module, configured to determine that an overcurrent occurs in the T-type three-level inverter, and the switch tube on the main bridge arm in the T-type three-level inverter is in a state of receiving a control signal;

A control module, configured to stop outputting a control signal to the switch tube on the main bridge arm in the T-type three-level inverter; from the stop to the main bridge arm in the T-type three-level inverter From the moment when the switching tube on the upper side outputs the control signal, after the first preset time period, the switching tube on the auxiliary bridge arm of the T-type three-level inverter that bears the reverse voltage outputs a turn-on signal, and the T-type three-level inverter The switch tube on the auxiliary bridge arm in the type three-level inverter is RB-IGBT.

An uninterruptible power supply provided by an embodiment of the present invention includes a T-type three-level inverter including RB-IGBT and a controller, and the switch tube on the auxiliary bridge arm in the T-type three-level inverter is RB-IGBT; the controller is used to determine that an overcurrent occurs in the T-type three-level inverter, and the switch tube on the main bridge arm in the T-type three-level inverter is in the state of receiving the control signal state; stop outputting a control signal to the switching tube on the main bridge arm in the T-type three-level inverter; from the stop to the switch on the main bridge arm in the T-type three-level inverter From the moment when the control signal is output by the tube, after the first preset time period, the switching tube that is subjected to the reverse voltage on the auxiliary bridge arm in the T-shaped three-level inverter outputs a turn-on signal;

The T-type three-level inverter is used to convert DC voltage into AC voltage under the control of the controller.

The beneficial effects of the embodiments of the present invention include:

The control method, device and uninterruptible power supply of the inverter including the RB-IGBT provided by the embodiment of the present invention will stop inverting to the T-type three-level inverter when the T-type three-level inverter overcurrent occurs. The switching tube on the main bridge arm in the inverter outputs a control signal, and from the moment when the switching tube on the main bridge arm in the T-type three-level inverter stops outputting the control signal, the first preset time period passes Afterwards, a turn-on signal will be output to the switching tube on the auxiliary bridge arm in the T-type three-level inverter that bears the reverse voltage, and the switching tube on the auxiliary bridge arm in the T-type three-level inverter is RB-IGBT, that is to say, after the switching tube on the main bridge arm in the T-type three-level inverter is turned off, the auxiliary bridge arm in the T-type three-level inverter The RB-IGBT that bears the reverse voltage is turned on, so that the RB-IGBT that bears the reverse voltage no longer bears the reverse voltage, avoids the generation of leakage current, and thus avoids the RB-IGBT that bears the reverse voltage The temperature rises sharply, protecting the RB-IGBT.

Description of drawings

FIG. 1 is a schematic structural diagram of a T-type three-level inverter including RB-IGBTs in the prior art;

FIG. 2 is a schematic structural diagram of a T-type three-level inverter including RB-IGBT provided by an embodiment of the present invention;

Fig. 3 is one of the flow charts of the control method of the inverter including RB-IGBT provided by the embodiment of the present invention;

Fig. 4a is the second flow chart of the control method of the inverter including RB-IGBT provided by the embodiment of the present invention;

Fig. 4b is the third flowchart of the control method of the inverter including RB-IGBT provided by the embodiment of the present invention;

Fig. 5a is the fourth flowchart of the control method of the inverter including RB-IGBT provided by the embodiment of the present invention;

Fig. 5b is the fifth flowchart of the control method of the inverter including RB-IGBT provided by the embodiment of the present invention;

Fig. 5c is the sixth flowchart of the control method of the inverter including RB-IGBT provided by the embodiment of the present invention;

Fig. 6a is the seventh flowchart of the control method of the inverter including RB-IGBT provided by the embodiment of the present invention;

Fig. 6b is the eighth flowchart of the control method of the inverter including RB-IGBT provided by the embodiment of the present invention;

Fig. 6c is the ninth flowchart of the control method of the inverter including RB-IGBT provided by the embodiment of the present invention;

FIG. 7 is a schematic structural diagram of a control device for an inverter including RB-IGBTs provided by an embodiment of the present invention.

detailed description

The control method, device and uninterruptible power supply of the inverter including RB-IGBT provided by the embodiment of the present invention, when an overcurrent occurs in the T-type three-level inverter, the T-type three-level inverter will The switching tube on the main bridge arm is turned off, and after the switching tube on the main bridge arm in the T-type three-level inverter is turned off, it will make the auxiliary power in the T-type three-level inverter The switch tube on the bridge arm that bears the reverse voltage is turned on. Since the switch tube on the auxiliary bridge arm in the T-type three-level inverter is an RB-IGBT, this will make the RB-IGBT that bears the reverse voltage not Then bear the reverse voltage, avoid the generation of leakage current, and then avoid the temperature rise of the RB-IGBT that bears the reverse voltage, and protect the RB-IGBT.

The protection method of the inverter including RB-IGBT provided by the embodiment of the present invention is applied to the T-type three-level inverter circuit shown in Fig. 2, and the T-type three-level inverter circuit shown in Fig. 2 includes control 21, filter 22, load 23 and T-type three-level inverter, wherein the T-type three-level inverter receives the DC voltage on the positive DC bus BUS+ and the negative DC bus BUS-, and outputs to the load 23 AC voltage; the T-type three-level inverter includes a first switching tube T1, a second switching tube T2, a third switching tube T3, a fourth switching tube T4, and a first diode connected in antiparallel with the first switching tube T1 The tube D1 and the second diode D2 connected in antiparallel with the fourth switch tube T4, wherein the second switch tube T2 and the third switch tube T3 are located on the auxiliary bridge arm of the T-type three-level inverter, and the second switch tube Both the tube T2 and the third switch tube T3 are RB-IGBT, the first switch tube T1 and the fourth switch tube T4 are located on the main bridge arm of the T-type three-level inverter, the first switch tube T1 and the fourth switch tube T4 are all traditional IGBTs. FIG. 2 also includes a first capacitor C1 and a second capacitor C2 connected in series between the positive DC bus BUS+ and the negative DC bus BUS-, and the point where the first capacitor C1 and the second capacitor C2 are connected is the midpoint N.

The specific implementations of a control method, device and uninterruptible power supply for an inverter including RB-IGBTs provided by the embodiments of the present invention will be described below with reference to the accompanying drawings.

A method for controlling an inverter including RB-IGBT provided in an embodiment of the present invention, as shown in FIG. 3 , includes:

S301. Determine that an overcurrent has occurred in the T-type three-level inverter, and the switching tube on the main bridge arm in the T-type three-level inverter is in a state of receiving a control signal; wherein the control signal includes a The turn-on signal and turn-off signal of the series; the control signal is used to control the switch tube in the T-type three-level inverter to switch between on and off, so that the output voltage of the T-type three-level inverter is at Switch between the positive bus BUS+ voltage, the voltage of the neutral point N and the negative bus BUS- voltage; the turn-on signal is used to control the conduction of the switch tube; the turn-off signal is used to control the switch tube to turn off;

S302. Stop outputting control signals to the switching tubes on the main bridge arm in the T-shaped three-level inverter; that is, stop outputting control signals to the first switching tube T1 and the fourth switching tube T4 in FIG. 2, so that Both the first switching tube T1 and the fourth switching tube T4 are turned off;

S303. From the moment when the output of the control signal to the switching tube on the main bridge arm of the T-type three-level inverter is stopped, after a first preset time period, send the signal to the T-type three-level inverter The switching tube on the auxiliary bridge arm in the inverter that bears the reverse voltage outputs a turn-on signal, and the switching tube on the auxiliary bridge arm in the T-shaped three-level inverter is an RB-IGBT.

As shown in Figure 2, the switch tube on the main bridge arm in the T-type three-level inverter is in the state of receiving the control signal, which means that the first switch tube T1 and the second switch tube T1 in the T-type three-level inverter The four switching transistors T4 are all in the state of receiving the control signal.

The overcurrent of the above-mentioned T-type three-level inverter includes two situations: one is the forward overcurrent of the T-type three-level inverter, that is, the T-type three-level inverter shown in Figure 2 In the circuit, the current flows from the filter 22 and the load 23 to the neutral point N, and the current on the inductor in the filter 22 in the T-type three-level inverter circuit is greater than the current threshold; the other is a type three Negative overcurrent occurs in the level inverter, that is, in the T-type three-level inverter circuit shown in Figure 2, the current flow direction is from the neutral point N, the load 23 to the filter 22, and the T-type three The current on the inductor in the filter 22 in the level inverter circuit is greater than the current threshold.

As shown in Figure 2, if a forward overcurrent occurs in the T-type three-level inverter, after stopping the output of the control signal to the switching tube on the main bridge arm in the T-type three-level inverter, the T-type Both the first switching tube T1 and the fourth switching tube T4 in the three-level inverter are turned off. Therefore, the T-type three-level inverter freewheels through the second diode D2, and the first switching tube T1 and the fourth switching tube T4 are turned off. The voltage at the connection point of the fourth switching tube T4 is the voltage of the negative bus BUS-, at this time, the switching tube that bears the reverse voltage on the auxiliary bridge arm of the T-type three-level inverter is the third switching tube T3, therefore, S303 is: starting from the moment when the output of control signals to the first switch tube T1 and the fourth switch tube T4 in the T-type three-level inverter is stopped, after a first preset time length, send the control signal to the T-type three-level inverter. The third switching tube T3 in the level inverter outputs a turn-on signal.

As shown in Figure 2, if a negative overcurrent occurs in the T-type three-level inverter, the T-type Both the first switching tube T1 and the fourth switching tube T4 in the three-level inverter are turned off. Therefore, the T-type three-level inverter freewheels through the second diode D1, and the first switching tube T1 and the fourth switching tube T4 are turned off. The voltage at the connection point of the fourth switching tube T4 is the voltage of the positive bus BUS+. At this time, the switching tube that bears the reverse voltage on the auxiliary bridge arm of the T-type three-level inverter is the second switching tube T2. Therefore, S303 It is: from the moment when the output of the control signal to the first switching tube T1 and the fourth switching tube T4 in the T-type three-level inverter is stopped, after the first preset time length, the T-type three-level inverter The second switching tube T2 in the flat inverter outputs a turn-on signal.

Wherein, the first preset duration may be preset, and the first preset duration may be the length of the dead time.

Optionally, as shown in Figure 4a, S301 specifically includes:

S401a. Obtain the current on the inductor in the filter connected to the output end of the T-type three-level inverter;

S402a. When the obtained current is greater than the current threshold, determine that the T-type three-level inverter has overcurrent; and determine that the switching tube on the main bridge arm in the T-type three-level inverter is in the receiving to the state of the control signal.

In practical applications, after obtaining the current on the inductor in the filter connected to the output end of the T-type three-level inverter, not only can it be judged according to the obtained current whether it is greater than the current threshold, but also the direction of the current can be determined. Thus it can be judged whether a positive overcurrent or a negative overcurrent occurs.

Optionally, as shown in Figure 4b, S301 specifically includes:

S401b. Obtain the reverse voltage borne by both ends of the switching tubes on the auxiliary bridge arm in the T-type three-level inverter except the control end;

As shown in Figure 2, the voltage difference Vce2 between the collector c and emitter e of the second switch tube T2 on the auxiliary bridge arm in the T-type three-level inverter is obtained, and the T-type three-level The voltage difference Vce3 between the collector c and the emitter e of the third switching tube T3 on the auxiliary bridge arm in the inverter

S402b. When the obtained reverse voltage has a reverse voltage greater than the voltage threshold, determine that the T-type three-level inverter has overcurrent; and determine that the main T-type three-level inverter The switch tube on the bridge arm is in the state of receiving the control signal;

In Fig. 2, when Vce2 is greater than the voltage threshold, it is determined that the T-type three-level inverter has positive overcurrent; when Vce3 is greater than the voltage threshold, it is determined that the T-type three-level inverter has negative overcurrent.

Further, the control method of the inverter including RB-IGBT provided by the embodiment of the present invention, as shown in Fig. 5a, Fig. 5b or Fig. 5c, further includes:

S501. From the start moment of outputting the turn-on signal to the switching tube on the auxiliary bridge arm of the T-type three-level inverter that bears the reverse voltage, after the second preset time period, stop supplying the T-type three-level inverter The switch tubes on the auxiliary bridge arm in the level inverter, except the switch tubes withstanding the reverse voltage, output control signals.

As shown in Figure 2, when a forward overcurrent occurs in the T-type three-level inverter, the switch tube that bears the reverse voltage on the auxiliary bridge arm in the T-type three-level inverter is the third switch tube T3 , therefore, S501 is: from the start moment of outputting the turn-on signal to the third switching tube T3 on the auxiliary bridge arm in the T-type three-level inverter, after the second preset time length, stop supplying The second switching tube T2 on the auxiliary bridge arm in the T-type three-level inverter outputs a control signal.

As shown in Figure 2, when a negative overcurrent occurs in the T-type three-level inverter, the switch tube that bears the reverse voltage on the auxiliary bridge arm in the T-type three-level inverter is the second switch tube T2 , therefore, S501 is: starting from the moment when the turn-on signal is output to the second switching tube T2 on the auxiliary bridge arm in the T-type three-level inverter, after the second preset time period, stop supplying The third switch tube T3 on the auxiliary bridge arm in the T-type three-level inverter outputs a control signal.

Wherein, the second preset duration may be preset, and the second preset duration may be the length of the dead time.

Optionally, if an overcurrent occurs in the T-type three-level inverter, instead of shutting down the T-type three-level inverter for a long time, it is necessary to After that, the T-type three-level inverter is temporarily shut down, and after the overcurrent of the T-type three-level inverter disappears, the T-type three-level inverter is restarted, then, the embodiment of the present invention The protection method of the T-type three-level inverter including RB-IGBT provided is shown in Fig. 6a, Fig. 6b or Fig. 6c. After the switching tubes other than the switching tubes withstanding the reverse voltage output the control signal, it also includes:

S601. Determine that the overcurrent of the T-type three-level inverter disappears;

When judging whether an overcurrent occurs in the T-type three-level inverter by obtaining the current on the inductor in the filter connected to the output end of the T-type three-level inverter, S601 is specifically: determine the obtained current Not greater than the current threshold;

When it is judged whether the T-type three-level inverter has occurred by obtaining the reverse voltage borne by the two ends of each switch tube on the auxiliary bridge arm except the control terminal in the T-type three-level inverter When the current is flowing, S601 is specifically: determine that the obtained reverse voltage is not greater than the voltage threshold, that is, both Vce2 and Vce3 are not greater than the voltage threshold;

S602. Output control signals to the switch tubes on the auxiliary bridge arm in the T-shaped three-level inverter except the switch tubes that bear the reverse voltage;

As shown in Figure 2, after the forward overcurrent of the T-type three-level inverter disappears, S602 is specifically: to send the second switching tube T2 on the auxiliary bridge arm in the T-type three-level inverter The switch tube outputs a control signal; after the negative overcurrent of the T-type three-level inverter disappears, S602 is specifically: to the third switch tube T3 on the auxiliary bridge arm in the T-type three-level inverter The switch tube outputs the control signal;

S603. From the start moment of outputting control signals to the switch tubes on the auxiliary bridge arm of the T-type three-level inverter except the switch tubes withstanding the reverse voltage, after a third preset time period, Outputting a control signal to the switching tube that bears the reverse voltage on the auxiliary bridge arm in the T-shaped three-level inverter;

As shown in Figure 2, after the forward overcurrent of the T-type three-level inverter disappears, S603 specifically: from the second switching tube on the auxiliary bridge arm in the T-type three-level inverter From the start moment when T2 outputs the control signal, after the third preset duration, the control signal is output to the third switch tube T3 on the auxiliary bridge arm in the T-type three-level inverter; in the T-type three-level inverter After the negative overcurrent of the inverter disappears, S603 is specifically: starting from the moment when the control signal is output to the third switching tube T3 switching tube on the auxiliary bridge arm in the T-shaped three-level inverter, after After the third preset duration, output a control signal to the second switching tube T2 on the auxiliary bridge arm in the T-type three-level inverter; wherein, the third preset duration can be preset, and the third preset The duration may be the duration of the dead time.

S604. From the moment when the control signal is output to the switching tube on the auxiliary bridge arm of the T-type three-level inverter that bears the reverse voltage, and after a fourth preset time period, send the control signal to the The switching tube on the main bridge arm in the T-type three-level inverter outputs the control signal;

As shown in Figure 2, after the forward overcurrent of the T-type three-level inverter disappears, S604 specifically: from the third switching tube on the auxiliary bridge arm in the T-type three-level inverter From the start moment when T3 outputs the control signal, after the fourth preset duration, the control signals are respectively output to the first switching tube T1 and the second switching tube T2 in the T-type three-level inverter; After the negative overcurrent of the level inverter disappears, S604 is specifically: starting from the moment when the control signal is output to the second switching tube T2 on the auxiliary bridge arm in the T-type three-level inverter, after After the fourth preset duration, control signals are respectively output to the first switching tube T1 and the second switching tube T2 in the T-type three-level inverter; wherein, the fourth preset duration can be preset, and the fourth The preset duration may be the duration of the dead time.

The control method of the inverter containing RB-IGBT provided by the embodiment of the present invention can also be applied to other inverter circuits containing RB-IGBT in series or in parallel, as long as the inverter circuit containing RB-IGBT in series or in parallel occurs In case of overcurrent, controlling the conduction of the RB-IGBT that bears the reverse voltage in the inverter circuit including RB-IGBT in series or parallel can avoid the leakage current of the RB-IGBT, thereby avoiding the problems of overheating and even failure of the RB-IGBT.

Based on the same inventive concept, the embodiment of the present invention also provides a control device and an uninterruptible power supply for an inverter containing RB-IGBT. Since the principle of the problem solved by the device and the uninterruptible power supply is the same as that of the aforementioned inverter containing RB-IGBT The control method of the inverter is similar, so the implementation of the device can refer to the implementation of the aforementioned method, and the repetition will not be repeated.

The control device of the inverter including RB-IGBT provided by the embodiment of the present invention, as shown in FIG. 7 , includes:

A determining module 71, configured to determine that an overcurrent occurs in the T-type three-level inverter, and the switch tube on the main bridge arm in the T-type three-level inverter is in a state of receiving a control signal;

The control module 72 is used to stop outputting a control signal to the switching tube on the main bridge arm in the T-type three-level inverter; from the stop to the main bridge in the T-type three-level inverter From the moment when the switch tube on the arm outputs the control signal, after the first preset time period, the switch tube on the auxiliary bridge arm in the T-shaped three-level inverter that bears the reverse voltage outputs a turn-on signal, and the The switch tube on the auxiliary bridge arm in the T-type three-level inverter is RB-IGBT.

Optionally, the determining module 71 is specifically configured to: obtain the current on the inductor in the filter connected to the output end of the T-type three-level inverter; when the obtained current is greater than a current threshold, determine the T An overcurrent occurs in the T-type three-level inverter; and it is determined that the switching tube on the main bridge arm in the T-type three-level inverter is in a state of receiving a control signal.

Optionally, the determining module 71 is specifically configured to: acquire the reverse voltages borne by both ends of the switching tubes on the auxiliary bridge arm in the T-shaped three-level inverter except the control terminal; When there is a reverse voltage greater than the voltage threshold in the reverse voltage, it is determined that an overcurrent occurs in the T-type three-level inverter; and it is determined that the switching tube on the main bridge arm in the T-type three-level inverter In the state of receiving the control signal.

Further, the control module 72 is also used for: starting from the moment when the switching tube on the auxiliary bridge arm of the T-type three-level inverter that bears the reverse voltage is outputting the turn-on signal, after a second preset time period and stop outputting control signals to the switching tubes on the auxiliary bridge arm in the T-shaped three-level inverter except for the switching tubes bearing the reverse voltage.

Further, the determining module 71 is also used for: after stopping outputting control signals to the switching tubes on the main bridge arm in the T-shaped three-level inverter except the switching tubes bearing the reverse voltage, determine the The overcurrent of the T-type three-level inverter disappears;

The control module 72 is also used to: output control signals to the switch tubes on the auxiliary bridge arm in the T-type three-level inverter except the switch tubes that bear the reverse voltage; From the moment when the switching tubes on the auxiliary bridge arm of the flat inverter other than the switching tubes that withstand the reverse voltage output control signals, after a third preset time length, the T-shaped three-level inverter On the auxiliary bridge arm in the inverter, the switching tube that bears the reverse voltage outputs a control signal; From the start moment when the tube outputs the control signal, after a fourth preset time period, the control signal is output to the switch tube on the main bridge arm in the T-shaped three-level inverter.

The uninterruptible power supply provided by the embodiment of the present invention includes a T-type three-level inverter circuit containing RB-IGBT shown in FIG. 2, the uninterruptible power supply includes a T-type three-level inverter and a controller 21; the T-type The three-level inverter is composed of the first switching tube T1, the second switching tube T2, the third switching tube T3, the fourth switching tube T4, the first diode D1 and the second diode D2 in Fig. 2 Inverter, wherein, the second switching tube T2 and the third switching tube T3 are located on the auxiliary bridge arm in the T-type three-level inverter, and both are RB-IGBT; the controller 21 is used to determine T Overcurrent occurs in the type three-level inverter, and the switching tube on the main bridge arm in the T-type three-level inverter is in the state of receiving the control signal; stop to the T-type three-level inverter The switching tube on the main bridge arm in the inverter outputs a control signal; from the moment when the output of the control signal to the switching tube on the main bridge arm in the T-type three-level inverter is stopped, after the first preset After a long period of time, output a turn-on signal to the switch tube that bears the reverse voltage on the auxiliary bridge arm in the T-shaped three-level inverter;

The T-type three-level inverter is used to convert the DC voltage into AC voltage under the control of the controller 21 .

Optionally, the controller 21 is specifically configured to: obtain the current on the inductor in the filter connected to the output end of the T-type three-level inverter; when the obtained current is greater than the current threshold, determine the T Overcurrent occurs in the type three-level inverter; and it is determined that the switching tube on the main bridge arm in the T-type three-level inverter is in the state of receiving the control signal; stop supplying the T-type three-level inverter The switching tube on the main bridge arm in the inverter outputs a control signal; from the moment when the output control signal is stopped to the switching tube on the main bridge arm in the T-type three-level inverter, after the first preset After the duration is set, a turn-on signal is output to the switching tube on the auxiliary bridge arm of the T-type three-level inverter that bears the reverse voltage.

Wherein, the controller 21 acquires the current on the inductance in the filter connected to the output end of the T-type three-level inverter, including two situations: one is that the controller 21 detects that the T-type three-level inverter The current on the inductor in the filter connected to the output end of the inverter; the second is that the uninterruptible power supply also includes a detection circuit, which detects the current on the inductor in the filter connected to the output end of the T-type three-level inverter. The controller 21 acquires the current detected by the detection circuit from the detection circuit.

Optionally, the controller 21 is specifically configured to: obtain the reverse voltage borne by the two ends of each switch tube on the auxiliary bridge arm in the T-shaped three-level inverter except the control terminal; When there is a reverse voltage greater than the voltage threshold in the reverse voltage, it is determined that an overcurrent occurs in the T-type three-level inverter; and it is determined that the switching tube on the main bridge arm in the T-type three-level inverter In the state of receiving the control signal; stop outputting the control signal to the switching tube on the main bridge arm in the T-type three-level inverter; from the stop to the T-type three-level inverter From the moment when the switch tube on the main bridge arm outputs the control signal, after a first preset time period, output a turn-on signal to the switch tube on the auxiliary bridge arm of the T-shaped three-level inverter that bears the reverse voltage.

Wherein, the reverse voltage borne by the two ends of each switch tube on the auxiliary bridge arm in the T-type three-level inverter described by the controller 21 except the control terminal includes two situations: one is that the controller 21 detects The reverse voltage that each switch tube on the auxiliary bridge arm in the T-type three-level inverter bears except the control terminal; the second is that the uninterruptible power supply also includes a detection circuit, which is detected by the detection circuit The controller 21 obtains the voltage detected by the detection circuit from the detection circuit for the reverse voltage borne by the two ends of each switch tube on the auxiliary bridge arm except the control terminal in the T-shaped three-level inverter.

Further, the controller 21 is also used for: starting from the start moment of outputting the turn-on signal to the switching tube on the auxiliary bridge arm of the T-type three-level inverter that bears the reverse voltage, after a second preset time period and stop outputting control signals to the switching tubes on the auxiliary bridge arm in the T-shaped three-level inverter except for the switching tubes bearing the reverse voltage.

Further, the controller 21 is also used for: after stopping the output of control signals to the switch tubes on the main bridge arm in the T-type three-level inverter except the switch tubes subjected to the reverse voltage, determine the The overcurrent of the T-type three-level inverter disappears; output control signals to the switch tubes other than the switch tubes that bear the reverse voltage on the auxiliary bridge arm in the T-type three-level inverter; From the start moment when the switch tubes on the auxiliary bridge arm of the T-type three-level inverter other than the switch tubes that withstand the reverse voltage output control signals, after a third preset time length, send to the T On the auxiliary bridge arm in the T-type three-level inverter, the switching tube that bears the reverse voltage outputs a control signal; from the auxiliary bridge arm in the T-type three-level inverter, the said From the start moment when the switching tube subjected to the reverse voltage outputs the control signal, after a fourth preset time period, the control signal is output to the switching tube on the main bridge arm in the T-shaped three-level inverter.

Through the above description of the implementation manners, those skilled in the art can clearly understand that the embodiments of the present invention can be implemented by hardware, or by means of software plus a necessary general hardware platform. Based on such understanding, the technical solutions of the embodiments of the present invention can be embodied in the form of software products, which can be stored in a non-volatile storage medium (which can be CD-ROM, U disk, mobile hard disk, etc.), Several instructions are included to make a computer device (which may be a personal computer, a server, or a network device, etc.) execute the methods described in various embodiments of the present invention.

Those skilled in the art can understand that the drawing is only a schematic diagram of a preferred embodiment, and the modules or processes in the drawing are not necessarily necessary for implementing the present invention.

Those skilled in the art can understand that the modules in the device in the embodiment can be distributed in the device in the embodiment according to the description in the embodiment, or can be located in one or more devices different from the embodiment according to corresponding changes. The modules in the above embodiments can be combined into one module, and can also be further divided into multiple sub-modules.

The serial numbers of the above embodiments of the present invention are for description only, and do not represent the advantages and disadvantages of the embodiments.

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (15)

1. A control method comprising a reverse-blocking insulated gate bipolar transistor RB-IGBT inverter, characterized in that, comprising: It is determined that an overcurrent occurs in the T-type three-level inverter, and the switching tube on the main bridge arm in the T-type three-level inverter is in a state of receiving a control signal; stop outputting control signals to the switching tubes on the main bridge arm in the T-shaped three-level inverter; From the moment when the output of the control signal to the switching tube on the main bridge arm in the T-type three-level inverter is stopped, after a first preset time length, the T-type three-level inverter The switch tube on the auxiliary bridge arm of the inverter that bears the reverse voltage outputs a turn-on signal, and the switch tube on the auxiliary bridge arm in the T-type three-level inverter is an RB-IGBT. 2. The method according to claim 1, wherein the determining that an overcurrent occurs in the T-type three-level inverter specifically comprises: Obtain the current on the inductor in the filter connected to the output end of the T-type three-level inverter; When the obtained current is greater than the current threshold, it is determined that the T-type three-level inverter has overcurrent. 3. The method according to claim 1, wherein the determining that an overcurrent occurs in the T-type three-level inverter specifically comprises: Obtain the reverse voltage borne by the two ends of each switch tube except the control end on the auxiliary bridge arm in the T-shaped three-level inverter; When there is a reverse voltage greater than the voltage threshold among the obtained reverse voltages, it is determined that the T-type three-level inverter has overcurrent. 4. The method according to any one of claims 1 to 3, further comprising: From the start moment of outputting the turn-on signal to the switching tube on the auxiliary bridge arm of the T-type three-level inverter that bears the reverse voltage, after the second preset time length, stop supplying to the T-type three-level inverter The switch tubes on the auxiliary bridge arm in the inverter other than the switch tubes withstanding the reverse voltage output control signals. 5. The method according to claim 4, characterized in that, the output control of the switching tubes other than the switching tubes bearing the reverse voltage on the main bridge arm in the T-shaped three-level inverter is stopped. After the signal, the method also includes: Determining that the overcurrent of the T-type three-level inverter disappears; Outputting control signals to the switch tubes on the auxiliary bridge arm in the T-shaped three-level inverter except the switch tubes that withstand the reverse voltage; From the start moment of outputting control signals to the switch tubes on the auxiliary bridge arm of the T-type three-level inverter except the switch tubes that withstand the reverse voltage, after the third preset time length, to all On the auxiliary bridge arm in the T-type three-level inverter, the switching tube that bears the reverse voltage outputs a control signal; From the start moment when the control signal is output to the switching tube on the auxiliary bridge arm in the T-type three-level inverter and subjected to the reverse voltage, after the fourth preset time length, the T-type The switch tube on the main bridge arm in the three-level inverter outputs a control signal. 6. A control device for an inverter comprising a reverse blocking insulated gate bipolar transistor RB-IGBT, characterized in that it comprises: A determining module, configured to determine that an overcurrent occurs in the T-type three-level inverter, and the switch tube on the main bridge arm in the T-type three-level inverter is in a state of receiving a control signal; A control module, configured to stop outputting a control signal to the switch tube on the main bridge arm in the T-type three-level inverter; from the stop to the main bridge arm in the T-type three-level inverter From the moment when the switching tube on the upper side outputs the control signal, after the first preset time period, the switching tube on the auxiliary bridge arm of the T-type three-level inverter that bears the reverse voltage outputs a turn-on signal, and the T-type three-level inverter The switch tube on the auxiliary bridge arm in the type three-level inverter is RB-IGBT. 7. The device according to claim 6, wherein the determining module is specifically used for: Obtain the current on the inductor in the filter connected to the output end of the T-type three-level inverter; When the obtained current is greater than the current threshold, it is determined that an overcurrent occurs in the T-type three-level inverter; and it is determined that the switching tube on the main bridge arm in the T-type three-level inverter is under the receiving control The state of the signal. 8. The device according to claim 6, wherein the determining module is specifically used for: Obtain the reverse voltage borne by the two ends of each switch tube except the control end on the auxiliary bridge arm in the T-type three-level inverter; When there is a reverse voltage greater than the voltage threshold in the obtained reverse voltage, it is determined that an overcurrent occurs in the T-type three-level inverter; and it is determined that the main bridge arm in the T-type three-level inverter The upper switch tube is in the state of receiving the control signal. 9. The device according to any one of claims 6-8, wherein the control module is further used for: From the start moment of outputting the turn-on signal to the switching tube on the auxiliary bridge arm of the T-type three-level inverter that bears the reverse voltage, after the second preset time length, stop supplying to the T-type three-level inverter The switch tubes on the auxiliary bridge arm in the inverter other than the switch tubes withstanding the reverse voltage output control signals. 10. The device according to claim 9, wherein the determining module is further configured to: After stopping to output control signals to the switch tubes on the main bridge arm in the T-type three-level inverter except the switch tubes that bear the reverse voltage, it is determined that the T-type three-level inverter is over flow disappears; The control module is also used for: Output control signals to the switch tubes on the auxiliary bridge arm in the T-type three-level inverter except the switch tubes that bear the reverse voltage; From the moment when the switching tubes on the bridge arm other than the switching tubes withstanding the reverse voltage output the control signal, after the third preset time length, the control signal is sent to the auxiliary bridge arm in the T-shaped three-level inverter. The switch tube that withstands the reverse voltage outputs a control signal; from the moment when the switch tube that withstands the reverse voltage outputs the control signal to the auxiliary bridge arm in the T-shaped three-level inverter After the fourth preset duration, the control signal is output to the switching tube on the main bridge arm in the T-shaped three-level inverter. 11. An uninterruptible power supply, comprising a T-type three-level inverter comprising a reverse blocking insulated gate bipolar transistor RB-IGBT, the auxiliary bridge arm in the T-type three-level inverter The switch tube is RB-IGBT, which is characterized in that it also includes a controller; The controller is used to determine that an overcurrent occurs in the T-type three-level inverter, and the switch tube on the main bridge arm in the T-type three-level inverter is in a state of receiving a control signal; The switching tube on the main bridge arm in the T-type three-level inverter outputs a control signal; the control signal is output from the stop to the switching tube on the main bridge arm in the T-type three-level inverter From the moment of , after the first preset time length, output a turn-on signal to the switch tube on the auxiliary bridge arm of the T-shaped three-level inverter that bears the reverse voltage; The T-type three-level inverter is used to convert DC voltage into AC voltage under the control of the controller. 12. The uninterruptible power supply according to claim 11, wherein the controller is specifically used for: Obtain the current on the inductor in the filter connected to the output end of the T-type three-level inverter; when the obtained current is greater than the current threshold, it is determined that the T-type three-level inverter has overcurrent; And it is determined that the switch tube on the main bridge arm in the T-type three-level inverter is in the state of receiving the control signal; output control signal; from the moment when the control signal is stopped outputting to the switching tube on the main bridge arm in the T-type three-level inverter, after a first preset time length, the T-type three-level inverter The switching tube that bears the reverse voltage on the auxiliary bridge arm in the flat inverter outputs a turn-on signal. 13. The uninterruptible power supply according to claim 11, wherein the controller is specifically used for: Acquiring the reverse voltage borne by the two ends of each switch tube on the auxiliary bridge arm in the T-type three-level inverter except the control terminal; in the obtained reverse voltage, there is a reverse voltage greater than the voltage threshold When the voltage is high, it is determined that an overcurrent occurs in the T-type three-level inverter; and it is determined that the switching tube on the main bridge arm in the T-type three-level inverter is in the state of receiving the control signal; The switch tube output control signal on the main bridge arm in the T-type three-level inverter; from the stop to the switch tube output control signal on the main bridge arm in the T-type three-level inverter From time to time, after a first preset period of time, a turn-on signal is output to the switching tube on the auxiliary bridge arm of the T-shaped three-level inverter that bears the reverse voltage. 14. The uninterruptible power supply according to any one of claims 11-13, wherein the controller is also used for: From the start moment of outputting the turn-on signal to the switching tube on the auxiliary bridge arm of the T-type three-level inverter that bears the reverse voltage, after the second preset time length, stop supplying to the T-type three-level inverter The switch tubes on the auxiliary bridge arm in the inverter other than the switch tubes withstanding the reverse voltage output control signals. 15. The uninterruptible power supply according to claim 14, wherein the controller is also used for: After stopping to output control signals to the switch tubes on the main bridge arm in the T-type three-level inverter except the switch tubes that bear the reverse voltage, it is determined that the T-type three-level inverter is over current disappears; output control signals to the switch tubes on the auxiliary bridge arm in the T-type three-level inverter except the switch tubes that withstand the reverse voltage; from the T-type three-level inverter to the From the start moment when the switching tubes on the auxiliary bridge arm except the switching tubes withstanding the reverse voltage output the control signal, after the third preset time length, the auxiliary bridge in the T-type three-level inverter On the bridge arm, the switching tube that withstands the reverse voltage outputs a control signal; from the output control signal to the switch tube that withstands the reverse voltage on the auxiliary bridge arm in the T-shaped three-level inverter From the start moment of , after a fourth preset time period, a control signal is output to the switching tube on the main bridge arm in the T-shaped three-level inverter.