阅读说明：本技术 用于对控制设备供应电压的启动电路、激励电路和方法 (Starting circuit, excitation circuit and method for supplying voltage to control device ) 是由 F·亨巴赫 L·布格斯塔勒 A·沙图拉 于 2020-04-29 设计创作，主要内容包括：本发明涉及用于变流器的控制设备的电压供应。特别地,对于变流器的控制实现可靠且稳定的电压供应,所述电压供应实现稳定的运行,其中在通过逆变器本身进行自给自足的电压供应和通过外部来源进行冗余的电压供应之间可以进行切换。(The invention relates to a voltage supply for a control device of a converter. In particular, a reliable and stable voltage supply is achieved for the control of the converter, which enables stable operation, wherein switching can be performed between a self-sufficient voltage supply by the inverter itself and a redundant voltage supply by an external source.)

1. A starting circuit (1) for voltage supply of a control device (20) of an electrical converter (2), the starting circuit having:

a first input terminal (11) designed to: is coupled to an electrical energy source (3);

a second input terminal (12) designed to: -an output terminal coupled to a voltage supply of the control device (20);

wherein the start-up circuit (1) is designed to:

generating a voltage (V _ IC) for supplying the control device (20) from a first voltage (V _ in) provided at the first input terminal (11) from the electrical energy source (3) in a first operating mode and providing it at the control device (20) when the voltage (V _ out) at the second input terminal (12) is below a preset first threshold value (SW 1),

providing a second voltage (V _ out) provided at the second input terminal (12) at the control device (20) in a second operating mode when the voltage (V _ out) at the second input terminal (12) exceeds a preset second threshold value (SW 2),

when the voltage (V _ in) at the first input terminal (11) exceeds a preset third threshold value (SW 3), a control signal (EN _ IC) for activating the voltage supply of the control device (20) is output in the first or second operating mode, and

-outputting a control signal (EN _ IC) for deactivating the voltage supply of the control device (20) in a third operating mode when the voltage (V _ in) at the first input terminal (11) is lower than the preset third threshold value (SW 3).

2. The startup circuit (1) according to claim 1, wherein the first threshold value (SW 1) is larger than the second threshold value (SW 2).

3. The start-up circuit (1) of claim 1 or 2, wherein the start-up circuit (1) comprises a voltage-reducing circuit designed to: converting a first voltage (V _ in) at the first input terminal (11) into a voltage having a predetermined voltage value and providing it at the control device (20).

4. A start-up circuit according to any of claims 1 to 3, wherein the first input terminal (11) is designed for: coupled with a high voltage battery of the electric vehicle.

5. Excitation circuit for an electrical converter (2), the excitation circuit having:

a control device (20) designed to: generating an excitation signal for the electric converter (2) and providing it at the converter (2);

a voltage supply circuit designed to: -providing a voltage for supplying energy to the control device (20); and

startup circuit (1) according to any of claims 1 to 4.

6. The excitation circuit of claim 5, wherein the voltage supply circuit is designed to: a voltage for supplying energy to the control device (20) is generated from the voltage of the electrical converter (2).

7. A method for supplying a voltage to a control device (20) of an electrical converter (2), the method having the following steps:

generating (S1) a voltage for supplying the control device (20) from a first voltage (V _ in) provided at a first input terminal (11) from an energy source (3) in a first operating mode when a voltage (V _ out) at a second input terminal (12) is below a preset first threshold value (SW 1), and providing the generated voltage (V _ IC) at the control device (20), wherein the second input terminal (12) is coupled with a voltage supply of the control device (20);

providing (S2) a second voltage (V _ out) applied at the second input terminal (12) at the control device (20) in a second operation mode when the voltage (V _ out) at the second input terminal (12) exceeds a preset second threshold (SW 2),

activating the voltage supply of the control device (20) in the first or second operating mode when the voltage (V _ in) at the first input terminal (11) exceeds a preset third threshold value (SW 3), and

deactivating (S3) the voltage supply of the control device (20) in a third operating mode when the voltage at the first input terminal (11) is below a preset third threshold (SW 3).

8. The method of claim 7, wherein the second threshold (SW 2) is greater than the first threshold (SW 1).

Technical Field

The invention relates to a starting circuit for the voltage supply of a control device, in particular for an electrical converter. The invention also relates to an excitation circuit for an electrical converter and to a method for supplying voltage to a control device, in particular for a control device of an electrical converter.

Background

Electrical converters, such as inverters, are used in a large number of fields of application. For example, an electrical converter is used in an electric vehicle to generate a voltage from a direct voltage, which excites an electric motor of the electric vehicle. For this purpose, the switching elements of such converters must be activated in a targeted manner. Control signals for this purpose are generated by means of a control device and supplied to the respective switching elements.

The reference EP 1531543 a2 discloses a method for supplying a multistrand, electrically switchable pulse width modulation-controlled electric motor from a dc power supply system.

Redundant voltage generating devices may be provided or even required for the voltage supply of the control devices of the converter. For example, in one aspect, the voltage supply may be implemented directly via a component of an inverter having a control circuit. Furthermore, a redundant voltage supply can be realized, for example by means of a high-voltage flyback circuit or the like.

For reliable operation of the converter, a safe voltage supply for the control device of the converter is desirable.

Disclosure of Invention

The invention provides a starting circuit for voltage supply of a control device, in particular of a control device for an electrical converter, and a method for supplying voltage to a control device, having the features of the independent claims. Further advantageous embodiments are the subject of the dependent claims.

It is therefore proposed:

a starting circuit for the voltage supply of a control device, in particular of an electrical converter. The start-up circuit includes a first input terminal and a second input terminal. The first input terminal is designed to: coupled to a source of electrical energy. The second input terminal is designed to: coupled to an output terminal for controlling a voltage supply of the device. The start-up circuit is designed to: in a first operating mode, a voltage for supplying the control device is generated from a first voltage, which is provided at the first input terminal, from the energy source. The start-up circuit is further designed to: the generated voltage is provided at the control device. The generation of the first voltage and the provision at the control device take place in particular when the voltage at the second input terminal is below a preset first threshold value. Furthermore, the start-up circuit is designed to: in a second operating mode, a second voltage provided at the second input terminal is provided at the control device. The second voltage is only provided at the second input terminal, in particular, if the voltage at the second input terminal exceeds a second predetermined threshold value. Furthermore, the start-up circuit is designed to: when the voltage at the first input terminal exceeds a preset third threshold value, a control signal for activating the voltage supply of the control device is output in the first operating mode or the second operating mode. Furthermore, the start-up circuit is designed to: when the voltage at the first input terminal is below a preset third threshold value, a control signal for deactivating the voltage supply of the control device is output in a third operating mode.

It is also proposed:

a drive circuit for an electrical converter has a control device, a voltage supply circuit and a start-up circuit according to the invention. The control device is designed to: an excitation signal for the electric converter is generated and provided at the converter. The voltage supply circuit is designed to: a voltage for supplying the control device with energy is provided. In particular, the voltage supply circuit may be designed for: the voltage from the current transformer is used to provide a voltage for supplying energy to the control device.

Finally, the method comprises the following steps:

a method for supplying a voltage to a control device, in particular a control device of an electrical converter. The method comprises the following steps: in a first operating mode, a voltage for supplying the control device is generated from a first voltage, which is provided at a first input terminal, from the energy source, and the generated voltage is provided at the control device when a voltage at a second input terminal, which is coupled to the voltage supply of the control device, is below a preset first threshold value. The method also includes the steps of: in a second operating mode, a second voltage applied at the second input terminal is provided at the control device when the voltage at the second input terminal exceeds a second predetermined threshold value. Furthermore, the method comprises the steps of: activating the voltage supply of the control device in the first or second operating mode when the voltage at the first input terminal exceeds a preset third threshold value, finally the method comprises the steps of: the voltage supply of the control device is deactivated in the third operating mode when the voltage at the first input terminal is below a preset third threshold value.

THE ADVANTAGES OF THE PRESENT INVENTION

The invention enables a safe and reliable voltage supply for a control device of an electrical converter. In particular, by flexibly setting the voltage threshold for switching into the first or second operating mode, respectively, a stable operating behavior can be achieved. For example, frequent switching between operating states due to small disturbances or short-term voltage variations can be prevented by appropriately setting the threshold value. Furthermore, the flexible configuration of the switching threshold also enables a reliable configuration of the operating point, so that dangerous operating states, for example, which could lead to overheating or the like, can be reliably prevented.

In addition, the switching between the individual operating states takes place within the starting circuit by means of state switching in accordance with a preset switching threshold. In this way, the start-up circuit is independent of external stimulus signals, in particular independent of software components of external components.

According to one embodiment, the first switching threshold value is greater than the second switching threshold value, below which the start-up circuit switches into the first operating mode, and above which the start-up circuit switches into the second operating mode. In this way, hysteresis may be defined by the difference between the two switching thresholds. This hysteresis prevents: early switching between the individual operating modes due to minor disturbances or short-term input voltage variations. This achieves stable and reliable operation.

According to one embodiment, the start-up circuit includes a voltage-reduction circuit. The voltage reduction circuit is designed to: the first voltage of the first input terminal is converted into a voltage having a predetermined voltage value. The converted voltage may be provided at the control device. In particular, the converted voltage may be provided as a voltage supply of the control device. With the aid of such a step-down circuit or another dc voltage converter, any external dc voltage can be converted in this way into a dc voltage which ensures the voltage supply of the converter during the start-up or warm-up of the control device for the converter.

According to one embodiment, the first input terminal is designed to: coupled with a high voltage battery, in particular of an electric vehicle. In this way, the voltage supply for the control circuit of the converter can be provided by the high-voltage battery as long as the converter itself cannot provide the voltage supply itself yet.

In one embodiment, the second voltage, i.e. the voltage provided at the output terminal of the voltage supply of the control device, is generated from the voltage of the converter. For example, the inverter, in particular the control device of the inverter, may comprise a voltage supply circuit for this purpose. For example, the voltage supply circuit can be an electrical circuit, in particular an integrated circuit, which generates a suitable voltage for supplying the voltage to the control device from the voltage available in the inverter.

The above-described embodiments and modifications can be combined with one another as desired, if appropriate. Other embodiments, modifications and embodiments of the invention also include combinations of features of the invention not explicitly mentioned above or described below with reference to the examples. In particular, the person skilled in the art will also add individual aspects as an improvement or supplement to the corresponding basic form of the invention.

Drawings

Further features and advantages of the invention are explained below with reference to the drawings. Here:

FIG. 1 shows a schematic diagram of a block diagram of an electric drive system having a converter and a start-up circuit, according to one embodiment;

FIG. 2 illustrates a schematic diagram of a state diagram upon which a startup circuit is based, according to one embodiment;

FIG. 3 shows a schematic diagram of a schematic circuit diagram upon which the startup circuit is based, according to one embodiment; and

fig. 4 shows a flow chart on which a method for supplying a voltage is based according to an embodiment.

Detailed Description

Fig. 1 shows a block diagram of an electric drive system with a starting circuit 1 for voltage supply of a control device of an electric converter 2 according to one embodiment. The electric drive system comprises an electric machine 4, a voltage supply 3, for example a high voltage battery or another direct voltage source, an inverter 2 and a start-up circuit 1. The dc voltage source 3 supplies a dc voltage to the one inverter 2. The direct voltage is converted by the inverter 2 into an alternating voltage suitable for driving the electric machine 4 according to an external rating specification (not shown here). For this purpose, a plurality of switching elements, for example semiconductor switching elements, of the inverter 2 can be driven by means of corresponding control signals. For generating the control signals, the inverter 2 comprises a control device 20 which provides corresponding control signals. The control device 20 requires a suitable voltage supply. During operation of the inverter 2, the voltage supply required for this purpose can be generated by the voltage itself available in the inverter 2. Such a supply voltage V _ out may be generated within the inverter 2, for example. For example, the supply voltage may be generated by means of a suitable electrical circuit, e.g. an integrated electrical circuit, such as a control IC or the like.

During operation of the inverter 2, operating states may exist, for example during system start-up, in particular during start-up of the inverter and the control circuit 20, wherein the control IC cannot yet be supplied with voltage independently. In this case, an additional external voltage supply is required. The external voltage supply and the switching between the internal and external voltage supply may be realized, for example, by means of the start-up circuit 1. The functional principle of the start-up circuit 1 is explained in more detail below.

An external voltage supply, for example a voltage supply from a direct voltage source 3, may be provided at the first input terminal 11 of the start-up circuit 1. During warm-up or start-up of the inverter 2, the start-up circuit 1 can generate the required voltage supply for the inverter 2, in particular the control circuit 20, from the voltage supplied by the direct voltage source 3. After the inverter 2 can maintain the independent voltage supply, the voltage V _ out generated by the inverter 2 can take over the voltage supply. For this purpose, the voltage V _ out generated by the inverter 2 is provided at the second input terminal 12 of the start-up circuit 1. The starting circuit 1 compares the voltage V _ out of the inverter 2 provided at the second input terminal 12 with a preset threshold value and uses the threshold value to control the voltage supply V _ IC of the inverter 2, in particular of the control device 20 for the inverter 2. For this purpose, the voltage V _ out provided by the inverter 2 may be provided to the inverter as a voltage supply V _ IC, or alternatively the start-up circuit may provide a voltage at the inverter 2, which voltage is generated from a direct voltage provided by the direct voltage source 3 at the first input terminal 11. Thus, the starting circuit 1 provides a voltage supply V _ IC at the inverter 2, which voltage supply implements for the inverter 2: the internal voltage regulating means, e.g. the control IC, is supplied with a voltage in order to maintain the internal voltage supply.

Furthermore, the startup circuit 1 can provide a further signal EN _ IC at the inverter, which activates or deactivates the internal voltage supply circuit of the inverter 2. For example, when the starting circuit 1 supplies a stable voltage V _ IC based on the voltage from the direct voltage source 3 or the voltage V _ out supplied by the inverter 2, the internal voltage supply may be activated by the activation signal EN _ IC. Otherwise, if a stable voltage is not supplied to voltage-supply the voltage supply circuit in the inverter 2, the control signal EN _ IC may deactivate the voltage supply circuit in the inverter 2.

Fig. 2 shows a schematic diagram of a state diagram of the operating mode of the startup circuit 1 according to an embodiment. In the first operating mode I during start-up, a sufficiently high dc voltage can be provided at the start-up circuit 1 by the dc voltage source 3. However, since the inverter 2 itself is not yet activated, the output voltage V _ out provided by the inverter 2 is lower than the preset first threshold value SW 1. In the first operating state, the starter circuit 1 therefore generates a voltage V _ IC at the inverter 2 from the direct voltage supplied by the direct voltage source 3 and supplies it at the inverter 2. For example, in the case of an electric drive system for an electric vehicle, a voltage V _ IC for an inverter of about 13V in magnitude may be generated from the voltage of the high-voltage battery 3. Further, the voltage supply circuit of the inverter 2 is activated by signaling the activation signal EN _ IC accordingly.

After the voltage supply circuit of the inverter 2 can ensure a stable voltage supply by the voltage within the inverter 2 and subsequently the output voltage V _ out at the inverter 2 exceeds the preset second threshold value SW2, the startup circuit 1 switches into the second operating mode II. In the second operating mode II, the voltage supply circuit within the inverter 2 is supplied by the output voltage V _ out of the inverter 2 via the starter circuit 1. Furthermore, the voltage supply circuit is activated by signaling the activation signal EN _ IC accordingly. In this case, it is no longer necessary for the starting circuit 1 to provide the voltage supply of the inverter with a direct voltage from the direct voltage source 3.

In order to prevent rapid switching between the first and second operating states I or II in the event of minor disturbances or voltage fluctuations, the second switching threshold SW2 may be set higher than the first switching threshold SW 1.

If the dc voltage supplied by the dc voltage source 3, for example the voltage supplied by the high-voltage battery of the electric vehicle, is first below a preset third threshold value SW3, for example because the high-voltage battery 3 is already separated from other components of the electric drive system, the starter circuit is switched into a third operating state, for example a sleep state. In this case, the voltage supply circuit of the inverter 2, for example, the control IC, is deactivated. Furthermore, the output voltage V _ out provided by the inverter 2 may be provided as a voltage supply at the inverter 2, in particular at the control circuit of the inverter 2, if necessary.

Fig. 3 shows a schematic diagram of a schematic circuit diagram which can be used as a basis for a starting circuit for the voltage supply of a control device for a converter. In order not to unduly expand the description, reference is made to the corresponding fig. 3 for a specific circuit configuration, and furthermore only some relevant components or circuit assemblies are explained in more detail. A voltage V _ IC for supplying a voltage supply circuit of the inverter 2, for example, for a suitable control IC or the like, may be generated from the direct-current voltage V _ in from the direct-current voltage source 3 via the semiconductor switch TI and the diode D1. The magnitude of the output voltage V _ IC can be set during the first operating mode, for example, by means of R1. Alternatively, the voltage V _ IC for the voltage supply circuit of the inverter 2 is provided via the diode D4 if the voltage of the output voltage V _ out of the inverter 2 is sufficiently high.

After the voltage V _ in from the dc voltage source 3 rises, the transistor TI starts to be turned on first. Immediately thereafter, the voltage at the resistor R4 begins to rise. The activation threshold can be set here via the chains R2-R3-R4 and R5-R6-D2. After the activation threshold is exceeded, T2 begins to conduct, whereby the activation signal EN _ IC is activated. Here, the voltage is limited by the base-emitter voltages of diodes D3 and T3. After the transistor T3 turns on, the hysteresis cancels due to the voltage drop across R4. Simultaneously activating the branch T4-R9-R10-T5.

At shutdown, the voltage V _ in of the dc voltage source is reduced below the zener voltage of diode D2, for example, by separating the high voltage battery from the electric drive system, and thus the base current of T2 is reduced below the switching condition. Thus, after a desired base current below T2, the circuit returns to the initial state.

In the case of an electric drive system for an electric vehicle, the dc voltage source 3 may, for example, comprise a high-voltage battery of the electric vehicle, which in turn may, for example, be 300 to 400V, if appropriate also higher, for example 800V or higher. The first threshold value SW1 for switching into the second operating state II may be, for example, of the order of magnitude of 14V. The second threshold value SW2 for switching into the first operating state may be, for example, of the order of 13V. Furthermore, the voltage generated by the starter circuit for the voltage supply of the inverter 2 in the first operating state can also be of the order of 13 volts. Of course, other threshold or voltage magnitudes are possible depending on the application.

Fig. 4 shows a schematic diagram of a flow chart on which a method for controlling the voltage supply of a device, in particular a control device for a converter, is based. In step S1, a voltage V _ IC for supplying the control device is generated. The voltage may in particular be generated from a voltage of the electrical energy source 2 which is provided at the first input terminal 11. The generated voltage may be provided at the control device 20 of the electrical converter 2. In particular, step S1 may be performed in the first operation mode when the voltage at the second input terminal 12 is lower than a preset first threshold value SW 1. The second input terminal 12 may be coupled with a voltage supply V _ out of the control device 20.

In the second operating mode, a second voltage V _ out applied at the second input terminal 12 can be provided at the control device 20 in step S2. In particular, the second voltage vout is provided in the second operating mode when the voltage vout at the second input terminal 12 exceeds a preset second threshold value SW 2. Here, the second threshold SW2 may be greater than the first threshold SW 1. In particular, the difference between the second threshold value SW2 and the first threshold value SW1 may include a preset hysteresis.

Furthermore, the voltage supply of the control device 20 can be activated in both the first operating mode and the second operating mode if the voltage V _ in at the first input terminal 11 exceeds a preset third threshold value SW 3.

In a third step S3, the voltage supply of the control device 20 may be deactivated in the third operating mode if the voltage V _ in at the first input terminal 11 is below a preset third threshold value SW 3.

In summary, the invention relates to a voltage supply for a control device of a converter. In particular, a reliable and stable voltage supply is achieved for the control of the converter, which enables stable operation, wherein switching can be performed between a self-sufficient voltage supply by the inverter itself and a redundant voltage supply by an external source.