EA043071B1 - DRIVE SYSTEM - Google Patents

Description

The invention described herein relates to a drive system that controls braking.

Description of the prior art

Regenerative braking and rheostatic braking in mechanized systems allows you to change the direction of the current in electromagnetic devices, such as electric motors, in order to slow down the movement of mechanized systems, such as vehicles. However, when the motorized system enters such a braking mode, the braking process occurs in discrete steps, since contactor switches are used for this, opening and closing to control the passage of electric current. This can lead to sparking and associated wear and tear on various circuit components in a motorized system, such as contactor switches and/or braking resistors. Wear and tear on these components may require additional maintenance, as well as additional costs to replace worn components.

The essence of the invention

In one or more embodiments, the present invention provides a drive system that may include resistive circuit legs connected to and located between a converter that converts electrical current for a motorized system motor and a source of electrical current to power the motor. Each branch of the circuit may contain a braking resistor connected to the converter. Each leg of the circuit may include a contactor connected to a brake resistor such that the brake resistor is located between the converter and the contactor. Each leg of the circuit may include a semiconductor switch connected to a contactor such that the contactor is located between the semiconductor switch and the brake resistor. When operating in the regenerative braking mode of the mechanized system, the energy recovered from the electric motor can be transferred to the braking resistor and dissipated as heat.

In yet another aspect, a drive system is provided that may include a brake resistor connected to a converter that converts electrical current to a motorized system motor, as well as several circuit legs that are connected to the brake resistor in parallel with each other. Each leg of the circuit may include a contactor and a semiconductor switch connected to the contactor such that the contactor is located between the semiconductor switch and the brake resistor. When operating in the regenerative braking mode of a mechanized system, the energy recovered from the electric motor can be transferred to the braking resistor and dissipated as heat, depending on which of the contactors or semiconductor switches are closed.

In one or more embodiments of the present invention, a drive system is provided that may include inductors. Each of the inductors may be configured to be placed on board the mechanized system and selectively connected to a first electrical current source and a converter that converts the electrical current to the motor of the mechanized system. In addition, each inductor may be connected to a circuit node between the drain of the semiconductor switch and the anode of the diode or controlled semiconductor switch. Each anode may be connected to the converter, with contactors connected in parallel to each other between the source of the first electrical current and the converter. Also, each anode can be connected to brake resistors connected in parallel to each other, with each brake resistor connected in series with a separate contactor, between this contactor and the converter. Also, each anode can be connected to a semiconductor switch connected to a contactor such that the contactor is located between the semiconductor switch and the brake resistors. In regenerative braking mode, rheostatic braking mode, or in a motorized system operation mode combined of these two modes of operation, the electric current regenerated from the electric motor can be transferred to the braking resistor and dissipated as heat, depending on which of the contactors or the first semiconductor switches are closed.

Brief description of the figures

The essence of the present invention can be understood in more detail by reading the following description of non-limiting embodiments of its implementation with reference to the attached drawings, where:

fig. 1 is a schematic view of a drive system in motor driven mode;

- 1 043071 fig. 2 is a schematic view of the boost drive system;

fig. 3 is a schematic view of a dynamic braking drive system;

fig. 4 is a schematic view of a drive system in a motor driven mode;

fig. 5 is a schematic view of the boost drive system;

fig. 6 is a schematic view of a dynamic braking drive system; fig. 7 is a schematic view of a dynamic braking drive system;

fig. 8 is a schematic view of a drive system in a motor driven mode; fig. 9 is a schematic view of a drive system in a motor driven mode; fig. 10 is a schematic view of a drive system in a motor driven mode; fig. 11 illustrates an example of a dynamic braking method in a drive system;

fig. 12 illustrates an example of a dynamic braking method in a drive system; and fig. 13 illustrates an example of a dynamic braking method in a drive system.

Detailed description of the invention

Embodiments of the invention described herein relate to a brake controlled drive system. Through the use of a solid-state switch, optionally in combination with a contactor and braking resistor, a controlled deceleration is achieved when the motorized system is braked. For example, switching, or opening and closing, a semiconductor switch may allow smaller discrete amounts of electric current to pass through the braking resistor. If the current is too high to be passed by one semiconductor switch, then another semiconductor switch can be used, capable of passing such a current, at least for a while. For example, one semiconductor switch may carry current a third of the time, a second semiconductor switch another third of the time, and a third semiconductor switch may carry current the remaining third of the time. This transfer of key control allows for continuous braking control of the motorized system. The duty cycles of each semiconductor switch determine how long the current will be allowed to flow through the braking resistor. The longer the operating cycle, the longer the time during which the semiconductor key is closed and passes current. The use of semiconductor switches in combination with brake resistors and contactor switches can reduce or even completely eliminate sparking, wear and damping of discrete components. This makes it possible to obtain a system with relatively fewer moving parts, so that manufacturing complexity and costs can be reduced.

The drive system may include a controller. In one embodiment of the present invention, a suitable semiconductor switch may be an insulated gate bipolar transistor (IGBT). A suitable contactor may be an electrically operated switch used to switch power circuits. The contactor can be driven by a circuit that has a lower voltage level than the switched circuit, such as a 74 volt coiled electromagnet driving a 1000 volt motor switch. In one embodiment of the present invention, the contactor may be a relay. In yet another embodiment, the contactor may have one or more features to control and suppress any sparks that occur when the electrical current is interrupted. A suitable braking resistor can be a resistor box capable of dissipating electrical current in the form of heat. Other suitable resistances may include devices that receive and/or control incoming electrical current. For example, any electrical circuit has an internal electrical resistance and therefore, to some extent, can be used as a resistive circuit. In one embodiment, the resistive circuit may include one or more electrical energy storage devices. In addition to having internal electrical resistance, electrical energy storage devices can act as electrical current storage devices. In yet another embodiment, the resistive circuit can receive and dispose of electrical current by performing work (as an alternative to or in addition to dissipating heat). For example, the resistive circuit may include an air compressor, and when the circuit is turned on, the compressor may operate as an air pump. In yet another embodiment, the resistive circuit is not on board the mechanized system, but is galvanically coupled to the mechanized system, for example by a catenary or a third rail. The operation of the off-board resistive circuit may be based on the internal resistance of the circuit and/or it may contain devices that provide a load and/or may contain energy storage devices. In non-limiting examples, a mechanized system may be a vehicle, wind turbine, or other system incorporating an electric motor. In other non-limiting examples, the motor may be used for propulsion, such as a traction motor, or for other purposes such as rotating the blades of a fan, wind turbine, and the like.

In FIG. 1, 2 and 3 illustrate the operation of the first embodiment of the drive system, respectively, in the driving mode with the help of the engine, in the forced driving mode and in the driving mode.

- 2 043071 dynamic braking. The illustrated diagrams show two electrical current sources, an on-board source and an off-board source. Alternatively, instead of an off-board source, the drive system may have another on-board source, such as a battery. Off-board electrical current source 124 may be a source of electrical power, such as a contact rail or catenary. The onboard source may be an engine and alternator assembly 102, an electrical energy storage device, or a battery. An off-board electrical current source is connected to the positive bus 111 and to the negative bus. The positive rail connects the electrical current source to the switch 122 and the inductor 120. The switch is located between the electrical current source and the inductor.

The inductance is connected to the collector of the semiconductor switch 116 and the anode of the diode 118. The cathode of the diode is connected in parallel with the circuit leg 126, which contains the contactor switch 115 and the brake resistor 114. A corresponding circuit node 128 is located between the contactor switch and the semiconductor switch. In the circuit arm, the contactor and the braking resistor are connected in series with each other. The arm itself is connected in parallel to the diode. The diode cathode and circuit arm containing the braking resistor and contactor are connected to the DC-AC converter 106 via the positive rail. The DC-AC converter is connected to the motor 108 by another positive bus 145 and another negative bus 140. A capacitor 110 is connected in parallel with the diode, circuit leg, and DC-AC converter. Negative Line Connected to Capacitor and DC-AC Converter Rectifier 104 is connected to the DC-AC converter by another positive line and another negative line. In the illustrated embodiment, the motor is a traction motor. Alternatively, the engine may not be a traction engine that generates torque to propel the vehicle. For example, an electric motor may power a pump or perform work other than propulsion.

In the motor driven mode, as shown in FIG. 1, the contactor located between the electric current source and the inductance is open, which does not allow current to flow from the electric current source. The motor-alternator kit supplies electrical power to the rectifier to provide power to the electric motor. Current 130 flows from the motor/alternator assembly to the motor. The rectifier can convert the AC voltage from the motor-alternator set to DC voltage, providing current to charge the capacitor. The current is supplied to the DC-AC converter. The DC-AC converter can convert DC to AC, supplying current to the motor. An electric motor uses alternating current to drive a mechanized system into translational motion.

Fig. 2 shows the drive system in boost mode. In the forced mode of operation, the contactor switch located between the source of electric current and the inductance is closed and passes current from the source of electric current along the positive bus. An electrical current source supplies electrical power to an inductor where the energy can be stored. Current can pass through the diode and power the motor. A capacitor connected to a source of electrical current through a negative bus can be charged, and an electric current can be supplied to the electric motor.

Fig. 3 shows the drive system in dynamic braking mode. The dynamic braking mode may be a regenerative braking mode, a dynamic braking mode, or a combination of the two. In regenerative or rheostatic braking mode, or a combination of the two modes, the contactor switch located between the electrical current source and the inductance is open and does not allow electrical current from the off-board electrical power source to the motor. However, the contactor switch located in the circuit arm is closed and passes the current from the motor through the braking resistor and the semiconductor switch. The regenerated energy from the motor is transferred to the braking resistor and dissipated as heat. Such a configuration with a closed switch, which is located between the source of electric current and the inductance, can be called an open state. The diagram shows the flow of electric current from the motor on the positive bus of the drive system 300 through the semiconductor switch. The current then flows through the negative rail to the capacitor, DC-AC converter, and back to the motor. In this embodiment, the capacitor is discharged and the motor provides voltage. The semiconductor switch can quickly switch open and closed states. Such fast modulation of the semiconductor switch allows smooth braking with controlled deceleration. For example, when a contactor located in a circuit arm is closed, modulation, or opening and closing, of the semiconductor switch allows smaller discrete amounts of electric current to pass through the braking resistor. If the current is too high for one semiconductor switch, then another semiconductor switch can be installed to carry the current at least for some time. TO

- 3 043071 For example, one semiconductor switch can pass current a third of the time, a second semiconductor switch another third of the time, and a third semiconductor switch can pass current the remaining third of the time. Such a change in the activity of the keys allows continuous control of the braking of the mechanized system. The duty cycles of each of the semiconductor switches determine how long the current will be allowed to flow through the braking resistor. The longer the operating cycle, the longer the time during which the semiconductor key is closed and passes current. The use of solid-state switches in combination with brake resistors and contactor switches can reduce sparking, wear and tear of discrete components, as well as reduce the number of moving parts, and therefore reduce production complexity and costs.

In FIG. 4-7 illustrate the operation of one embodiment of the drive system, respectively, in the driving mode with the help of the engine, in the forced driving mode and in the dynamic braking mode. The diagrams show two sources of electrical current, an onboard source and an off-board source of electrical current. Alternatively, the drive system may have another on-board source, such as a battery, instead of an off-board electrical source. The source of electrical current 424 may be a source of electrical power, such as a contact rail or catenary. The on-board power supply 402 may be a combination of an engine and an alternator, an electrical energy storage device (eg, a battery), or the like. An electrical current source is connected to positive bus 411 and negative bus 412. The positive bus connects the electrical current source to switch 422 and inductance 420. The switch is located between the electrical current source and the inductor.

The inductance is connected to the collector of the first semiconductor switch 416 and the emitter of the second semiconductor switch 418. The collector of the second semiconductor switch is connected in parallel with the circuit leg 426, which contains the contactor switch 415 and the brake resistor. The corresponding circuit node 428 is located between the contactor switch and the first semiconductor switch. In the circuit arm, the contactor and the braking resistor are connected in series with each other. The chain arm itself is connected in parallel with the second semiconductor key. The collector of the second solid-state switch and the circuit leg containing the braking resistor and contactor are connected to the DC-AC converter 406 via the positive rail. The DC-AC converter is connected to the motor 408 via another positive line 445 and another negative line 440. Capacitor 410 is connected in parallel with the second semiconductor switch, the circuit leg, and the DC-AC converter. The off-board electric current source is connected to the emitter of the first semiconductor switch by a negative bus. Negative Line Connected to Capacitor and DC-AC Converter Rectifier 404 is connected to the DC-AC converter by another positive line and another negative line. In the illustrated embodiment, the motor is a traction motor.

In the powered driving mode shown in FIG. 4, the motor-alternator kit supplies electrical power to the rectifier to power the electric motor. Current 430 is supplied from the motor-alternator kit to the electric motor. The rectifier can convert the AC voltage from the motor-alternator set to DC voltage, providing current to charge the capacitor. The current is supplied to the DC-AC converter. The DC-AC converter can convert DC to AC, supplying current to the motor. An electric motor uses alternating current to drive a mechanized system.

Fig. 5 shows the drive system in boost mode. In the forced movement mode, the contactor switch, located between the source of electric current and the inductance, is closed and passes current from the source of electric current along the positive bus. An electrical current source supplies electrical power to an inductor where the energy can be stored. Current can be passed through the second semiconductor switch to power the motor. A capacitor connected to a source of electrical current by a negative bus can be charged, and an electric current can be supplied to the electric motor.

Fig. 6 shows the drive system in dynamic braking mode. The dynamic braking mode may be a regenerative braking mode, a dynamic braking mode, or a combination of the two. In regenerative or rheostatic braking mode, or a combination of the two modes, a contactor switch located between the electrical current source and the inductance is closed and passes electrical current to the off-board electrical current source. However, the contactor switch located in the circuit arm is open and does not pass current through the braking resistor. The diagram shows the flow of electric current from the motor (load) through the positive bus of the drive system to the DC-AC converter through another positive bus, and into the capacitor through the semiconductor switches. The first semiconductor key can pass an electric current. The second semiconductor switch can quickly switch between open and closed states. Such a fast modulation of the second semiconductor

- 4 043071 keys allows smooth braking with controlled deceleration. For example, when a contactor located in a circuit arm is closed, modulation, or opening and closing, of the first semiconductor switch allows smaller discrete amounts of electric current to flow through the braking resistor. If the current is too high for the first semiconductor switch, then another semiconductor switch may be installed to pass at least part of the current. For example, the first semiconductor switch may carry current for a third of the time, another semiconductor switch for another third of the time, and the third semiconductor switch may carry current for the remaining third of the time. Such a change in the activity of the keys allows for continuous control of the braking of the mechanized system. The duty cycles of each of the semiconductor switches determine how long the current will be allowed to flow through the braking resistor. The longer the operating cycle, the longer the time during which the semiconductor key is closed and passes current. The use of solid-state switches in combination with brake resistors and contactor switches reduces sparking, wear and tear of discrete components, as well as a reduction in the number of moving parts, and therefore reduces production complexity and costs. The current can continue to flow to the off-board power supply and back to the motor on the positive rail, passing through the semiconductor switch emitter junction, capacitor, DC-AC converter, and back to the motor on another negative rail. In this embodiment, the capacitor is discharged and the motor provides voltage.

Fig. 7 shows the drive system in dynamic braking mode. The dynamic braking mode may be a regenerative braking mode, a dynamic braking mode, or a combination of the two. In regenerative or rheostatic braking mode, or a combination of the two modes, the contactor switch located between the electrical current source and the inductance is open and does not pass electrical current to the off-board electrical source. However, the contactor switch located in the circuit arm is closed and passes current from the electric motor through the braking resistor and the first and second semiconductor switches. The second semiconductor switch may simply pass current, while the first semiconductor switch may quickly switch between open and closed states. The regenerated energy from the motor is transferred to the braking resistor and dissipated as heat. Fast modulation of the first semiconductor switch allows smooth braking with controlled deceleration. For example, when a contactor located in a circuit leg is closed, modulation, or opening and closing, of the first semi-conductor switch can cause smaller discrete amounts of electric current to pass through the braking resistor. If the current that the first semiconductor switch can pass exceeds a predetermined threshold value, then another semiconductor switch can be set to pass at least part of the current. For example, the first semiconductor switch may carry current for a third of the time, another semiconductor switch for another third of the time, and the third semiconductor switch may carry current for the remaining third of the time. Such a change in the activity of the keys allows for continuous control of the braking of the mechanized system. The duty cycles of each semiconductor switch determine how long the current will be allowed to flow through the braking resistor. The longer the operating cycle, the longer the time during which the semiconductor key is closed and passes current. The use of solid-state switches in combination with brake resistors and contactor switches can reduce sparking, wear and tear of discrete components, as well as reduce the number of moving parts, and therefore reduce production complexity and costs. In this circuit, current can flow from the semiconductor switch on the negative rail of the drive system 700, through the capacitor, the DC-AC converter, and on to the motor on another negative rail. In this embodiment, the capacitor is discharged and the motor provides voltage.

In FIG. 8 illustrates the operation of one embodiment of the drive system. The drive system can be operated, respectively, in the drive mode from the engine, in the forced drive mode or in the dynamic braking mode. The diagram shows two sources of electrical current, an on-board source and an off-board source. Alternatively, the drive system may have another on-board source, such as a battery, instead of an off-board source. Off-board electrical current source 824 may be a source of electrical power, such as a conductor rail or catenary.

The onboard source may be an engine and alternator assembly 802, an electrical energy storage device, or a battery. An off-board electrical current source may be connected to positive rail 811 and negative rail 812. The positive rail connects the electrical current source to switch 822 and inductors 820 connected in parallel with each other. The switch is located between the electric current source and the inductors. Each of these inductances is connected to the collector of the semiconductor switch 816, which is one of the semiconductor switches, and to the anode of the diode 818, which is

- 5 043071 is one of the diodes. Diode cathodes are connected in parallel with circuit arms 826 containing contactor switches 812 and brake resistors 814. Corresponding circuit nodes 828 are located between the contactor switches and semiconductor switches. In at least some of the legs of the circuit, the contactor and the braking resistor are connected to each other in series. The legs of the circuit are connected in parallel with the diodes. Diode cathodes and circuit legs containing braking resistors and contactors may be connected to the DC-AC converter 806 via the positive rail. The DC-AC converter may be connected to the motor 808 with another positive rail 845 and another negative rail 840. Capacitor 810 may be connected in parallel with the diodes, legs, and DC-AC converter. The off-board electric current source can be connected to the emitters of semiconductor switches by a negative bus. The negative rail can be connected to a capacitor and to a DC-AC converter. In the illustrated embodiment, the motor is a traction motor.

In motor-driven mode, the motor-alternator assembly supplies electrical power to the 804 rectifier to power the motor. The contactors are open so current is supplied from the motor-alternator set to the motor. The rectifier can convert the AC voltage from the motor-alternator set to DC voltage, providing current to charge the capacitor. The current is supplied to the DC-AC converter. The DC-AC converter can convert DC to AC, supplying current to the motor. An electric motor can use alternating current to drive a mechanized system.

Alternatively, the drive system may operate in a forced motion mode. In the forced movement mode, the contactor switch located between the electric current source and the inductances is closed and passes current from the electric current source along the positive bus. The contactors located in the resistive legs of the circuit are open. An electric current source delivers electricity to inductors where energy can be stored. The power source may be an off-board power source, such as a conductor rail or catenary, or an on-board power source, such as a power storage device or battery. Current can pass through the diodes to power the motor. A capacitor connected to an electrical current source by a negative bus can be charged, and an electric current can be supplied to the electric motor.

Alternatively, the drive system may operate in dynamic braking mode. The dynamic braking mode may be a regenerative braking mode, a dynamic braking mode, or a combination of the two. In regenerative or rheostatic braking mode, or a combination of the two modes, the contactor switch located between the electrical current source and the inductors is open and does not pass electrical current from the off-board electrical current source. However, at least one of the contactor switches located in the legs of the circuit is closed and passes the current from the electric motor through the respective braking resistors and the respective semiconductor switches. The recovered energy from the motor can be transferred to at least some of the brake resistors and dissipated as heat. Semiconductor switches can quickly switch open and closed states. Such fast modulation of semiconductor switches allows for smooth braking with controlled deceleration. For example, when the contactor in the legs of the circuit is closed, the modulation, or opening and closing, of the semiconductor switch allows smaller discrete amounts of electric current to pass through the braking resistor. If the current is too high for one semiconductor switch, then another semiconductor switch can be installed to carry the current, at least for some time. For example, one semiconductor switch may pass current a third of the time, a second semiconductor switch another third of the time, and a third semiconductor switch may pass current the remaining third of the time. Such a change in the activity of the keys allows for continuous control of the braking of the mechanized system. The duty cycles of each of the semiconductor switches determine how long the current will be allowed to flow through the braking resistor. The longer the operating cycle, the longer the time during which the semiconductor key is closed and passes current. The use of solid-state switches in combination with brake resistors and contactor switches reduces sparking, wear and tear on discrete components, as well as fewer moving parts and therefore lower manufacturing complexity and costs. Current flows from the semiconductor switches on the negative bus of the drive system 800, through the capacitor, the DC-AC converter, and on to the motor. In this embodiment, the capacitor is discharged and the motor provides voltage.

In FIG. 9 illustrates the operation of one embodiment of the drive system. The drive system can be operated, respectively, in the drive mode from the engine, in the forced drive mode or in the dynamic braking mode. The diagram shows two sources of electrical current, an on-board source and an off-board source. Alternatively, drive system instead of outboard

- 6 043071 of this source may have another on-board source, for example, a battery. Off-board electrical current source 924 may be a source of electrical power, such as a conductor rail or catenary. The onboard source may be an alternator engine kit 902, an electrical energy storage device, or a battery. An off-board electrical current source may be connected to positive bus 911 and negative bus 912. The positive bus connects the electrical current source to switch 922 and to inductors 920 connected in parallel with each other. The switch is located between the electric current source and the inductors. Each inductance of these inductances is connected to the collector of the semiconductor switch 916, which is one of the semiconductor switches, and to the anode of the diode 918, which is one of the diodes. The cathodes of the diodes are connected in parallel with a circuit leg 926 which contains a braking resistor 914 connected in series with the rest of the circuit legs connected in parallel with each other. Each of the other legs of the circuit contains a contactor 915. The circuit leg with the brake resistor and the contactors connected in parallel with each other is connected in parallel with the diodes. The corresponding circuit nodes 928 are located between the contactor switches and the semiconductor switches. Diode cathodes and a circuit arm containing a braking resistor and contactors connected in parallel with each other can be connected to a DC-AC converter 906 via a positive rail. The DC-AC converter may be connected to the motor 908 with another positive rail 945 and another negative rail 940. Capacitor 910 may be connected in parallel with the diodes, legs, and DC-AC converter. The off-board electric current source can be connected to the emitters of semiconductor switches by a negative bus. The negative bus may be connected to a capacitor and to a DC-AC converter. In the illustrated embodiment, the motor is a traction motor.

In motor-driven mode, the motor-alternator assembly supplies electrical power to the 804 rectifier to power the motor. The contactors are open, so current is supplied from the motor-alternator set to the electric motor. The rectifier can convert the AC voltage from the motor-alternator set to DC voltage, providing current to charge the capacitor. The current is supplied to the DC-AC converter. The DC-AC converter can convert DC to AC, supplying current to the motor.

Alternatively, the drive system may operate in a forced motion mode. In the forced movement mode, the contactor switch, located between the electric current source and the inductances, is closed and passes current from the electric current source along the positive bus. The contactors located in the circuit arms are open.

An electric current source delivers electricity to inductors where energy can be stored. The power source may be an off-board power source, such as a conductor rail or catenary, or an on-board power source, such as a power storage device or battery. Current can pass through the diodes to power the motor. A capacitor connected to a source of electrical current by a negative bus can be charged, and an electric current can be supplied to the electric motor.

Alternatively, the drive system may operate in dynamic braking mode. The dynamic braking mode may be a regenerative braking mode, a dynamic braking mode, or a combination of the two. In regenerative or rheostatic braking mode, or a combination of the two modes, the contactor switch located between the electrical current source and the inductors is open and does not pass electrical current from the off-board power source. The regenerated electrical current from the motor is transferred to the braking resistor and dissipated as heat. However, at least one of the contactor switches located in the legs of the circuit is closed and passes current from the electric motor through the braking resistor and the corresponding semiconductor switches. Semiconductor switches can quickly switch open and closed states. This fast modulation of the semiconductor switches enables smooth braking with controlled deceleration. For example, when the contactor in the legs of the circuit is closed, modulation, or opening and closing of the semiconductor switch, allows smaller discrete amounts of electric current to pass through the braking resistor. If the current is too high for one semiconductor switch, then another semiconductor switch can be installed to carry the current, at least for some time. For example, one semiconductor switch may carry current a third of the time, a second semiconductor switch another third of the time, and a third semiconductor switch may carry current the remaining third of the time. Such a change in the activity of the keys allows for continuous control of the braking of the mechanized system. The duty cycles of each semiconductor switch determine how long the current will be allowed to flow through the braking resistor. The longer the operating cycle, the longer the time during which the semiconductor key is closed and passes current. The use of semiconductor switches in combination with

- 7 043071 brake resistors and contactor switches allows to reduce sparking, wear and tear of discrete components, as well as to reduce the number of moving parts, and therefore reduce production complexity and costs. Current flows from the semiconductor switches through the negative bus of the drive system 900 to the capacitor, the DC-AC converter, and on to the motor. In this embodiment, the capacitor is discharged and the motor provides voltage.

In FIG. 10 illustrates the operation of one embodiment of the drive system. The drive system can operate in engine driven mode, forced drive mode, or dynamic braking mode. The diagram shows two sources of electrical current, an on-board source and an off-board source. Alternatively, the drive system may have another on-board source, such as a battery, instead of an off-board source. Off-board electrical current source 1024 may be a source of electrical power, such as a conductor rail or catenary. The onboard source may be an alternator engine kit 1002, an electrical energy storage device, or a battery. An off-board electrical current source may be connected to a positive bus 1011 and a negative bus 1012. The positive bus connects the electrical current source to the switch 1022. The positive bus connects the electrical current source to a circuit leg connected in series with the remaining circuit legs 1026 connected to each other in series. In each of the legs of the circuit, the contactor 1015 and the braking resistor 1014 are connected to each other in series. The positive rail connects the inductors 1020 connected in parallel to each other. The switch is located between the electric current source and the inductors. Each inductor is connected to the commutator of the semiconductor switch 1016, which is one of the semiconductor switches, and to the anode of the diode 1018, which is one of the diodes. Diode cathodes are connected in parallel with circuit arms containing contactor switches and braking resistors.

The corresponding circuit nodes 1028 are located between the contactor switches and the semiconductor switches. The legs of the circuit are connected in parallel with the diodes. Diode cathodes and circuit legs containing braking resistors and contactors may be connected to the DC-AC converter 1006 via the positive rail. The DC-AC converter may be connected to the motor 1008 with another positive rail and another negative rail. The capacitor 1010 may be connected in parallel with the diodes and with the DC-AC converter. The off-board electric current source can be connected to the emitters of semiconductor switches by a negative bus. Negative Line May Be Connected to Capacitor and to DC-AC Converter Rectifier 404 may be connected to DC-AC converter by another positive line 1045 and another negative line 1040. In the illustrated embodiment, the motor is a traction motor.

In engine-driven mode, the engine-alternator package supplies power to the rectifier to power the electric motor. The contactors are open, so current is supplied from the motor-alternator set to the electric motor. The engine-alternator set can run on a fuel such as diesel fuel. The motor-alternator set can produce alternating current for ancillary purposes such as lighting. The rectifier can convert the AC voltage from the motor-alternator set to DC voltage, providing current to charge the capacitor. Current is supplied to the DC-AC converter. The DC-AC converter can convert DC to AC, supplying current to the motor.

Alternatively, the drive system may operate in a forced motion mode. In the forced movement mode, the contactor switch located between the electric current source and the inductances is closed and passes current from the electric current source along the positive bus. All contactors are open. An electric current source supplies electric power to inductors located in the legs of the circuit, where energy can be stored. The power source may be an off-board power source, such as a conductor rail or catenary, or an on-board power source, such as a power storage device or battery. Current can pass through the diodes to power the motor. A capacitor connected to an electrical current source by a negative bus can be charged, and an electric current can be supplied to the electric motor.

Alternatively, the drive system may operate in dynamic braking mode. The dynamic braking mode may be a regenerative braking mode, a dynamic braking mode, or a combination of the two. In regenerative or rheostatic braking mode, or a combination of the two modes, the contactor switch located between the electrical current source and the inductors is open and does not pass electrical current from the off-board electrical current source. However, at least one of the contactor switches located in the legs of the circuit is closed and passes the current from the electric motor through the corresponding braking resistor, the corresponding inductances and the corresponding semiconductor switches. The regenerated energy from the electric motor is transferred to the braking resistor and

- 8 043071 is dissipated as heat. Semiconductor switches can quickly switch open and closed states. Such fast modulation of semiconductor switches allows for smooth braking with controlled deceleration. For example, when a contactor in the legs of the circuit is closed, modulation, or opening and closing, of the semiconductor switch allows smaller discrete amounts of electric current to flow through the braking resistor. If the current is too high for one semiconductor switch, then another semiconductor switch can be installed to carry the current, at least for some time. For example, one semiconductor switch may carry current a third of the time, a second semiconductor switch another third of the time, and a third semiconductor switch may carry current the remaining third of the time. Such a change in the activity of the keys allows for continuous control of the braking of the mechanized system. The duty cycles of each semiconductor switch determine how long the current will be allowed to flow through the braking resistor. Alternatively, the semiconductor switches can close and open at the same time. The longer the operating cycle, the longer the time during which the semiconductor key is closed and passes current. The use of solid-state switches in combination with brake resistors and contactor switches reduces sparking, wear and tear of discrete components, as well as a reduction in the number of moving parts, and therefore reduces production complexity and costs. Current flows from the semiconductor switches on the negative bus of the drive system 1000, through the capacitor, the DC-AC converter, and on to the motor. In this embodiment, the capacitor is discharged and the motor provides voltage.

In FIG. 11 shows an example of a method for regenerative braking, dynamic braking, or a combination thereof in the drive system illustrated in FIG. 8. In step 1102, the regenerated energy comes from the motor. For example, an electric motor can act as a power source for a drive system. The electric motor can work as a generator, supplying energy previously taken from other sources of electricity, such as batteries. The current from the electric motor is supplied to the DC-AC converter. The current can be alternating (AC). Current can flow to the DC-AC converter through the positive rail located between the motor and the DC-AC converter. The DC-AC converter can convert alternating current to direct current (DC).

At 1104, current flows from the DC-AC converter through another positive rail to the capacitor. For example, the current may flow between the DC-AC converter and the capacitor on a different positive bus than the bus between the motor and the DCAC. Alternatively, current can flow from the DC-AC converter on the same busbar between the motor and the DC-AC converter.

In step 1106, the capacitor is discharged. For example, in regenerative braking mode, rheostatic braking mode, or a combination of the two modes, the energy stored in the battery can drain to the positive rail. The current can then be fed to the braking resistors.

At 1108, since the contactor is closed, current flows to the brake resistors and is dissipated as heat. For example, at least one of the contactor switches may be closed and current flow through the respective braking resistors to the positive rail. Current may not be allowed to flow through the positive rail through the diodes due to the forward bias voltage in them. In this embodiment, the diodes can be oriented so as to prevent the flow of current in a given branch of the circuit. Alternatively, another semiconductor switch can be used, such as an IGBT transistor, which allows current to pass through the component in both directions.

At 1110, current flows through the semiconductor switches. For example, modulating, or opening and closing, semiconductor switches allow smaller discrete amounts of electric current to pass through the braking resistance. If the current is too high for one semiconductor switch, then another semiconductor switch can be installed to carry the current, at least for some time. For example, one semiconductor switch may carry current a third of the time, a second semiconductor switch another third of the time, and a third semiconductor switch may carry current the remaining third of the time. Such a change in the activity of the keys allows for continuous control of the braking of the mechanized system. The duty cycles of each semiconductor switch determine how long the current will be allowed to pass through the braking resistor. The longer the operating cycle, the longer the time during which the semiconductor key is closed and passes current. The use of solid-state switches in combination with brake resistors and contactor switches reduces sparking, wear and tear of discrete components, as well as a reduction in the number of moving parts, and therefore reduces production complexity and costs. In regenerative braking mode, since the contactors are closed, other power sources can be bypassed. Accordingly, the current flows through the negative bus of the drive system to the capacitor.

At 1112, current is supplied to the capacitor. For example, current can flow in a negative

- 9 043071 tire. The negative rail is connected to the capacitor pole that is not connected to the positive rail. Current is supplied on the negative bus through the connection point of the capacitor to the converter

DC-AC.

At 1114, current flows to the DC-AC converter on the negative rail. For example, the negative terminal of a DC-AC converter can be connected to the negative rail. The DC-AC converter can convert the DC to AC needed by the motor in regenerative braking, dynamic braking, or a combination of the two. Current flows from the DC-AC converter to the motor.

At 1116, current is supplied to the motor. For example, current can be drawn from the DC-AC converter through another negative rail. Alternatively, the current can flow through the same negative rail that the rest of the circuit is connected to. In regenerative braking mode, the electric motor is the power source for the drive system. In this mode, the system can work as required, providing controlled braking and smooth deceleration.

In FIG. 12 shows an example of a method for regenerative braking, dynamic braking, or a combination thereof in the drive system illustrated in FIG. 9. In step 1202, the regenerated energy comes from the motor. For example, an electric motor can act as a power source for a drive system. The electric motor can work as a generator, giving off energy previously taken from other sources of electricity, such as batteries. The current from the electric motor is supplied to the DC-AC converter. The incoming current can be alternating (AC). Current can flow to the DC-AC converter through the positive rail located between the motor and the DC-AC converter. The DC-AC converter can convert alternating current to direct current (DC).

At 1204, current flows from the DC-AC converter through another positive rail to the capacitor. For example, the current may flow between the DC-AC converter and the capacitor on a different positive bus than the bus between the motor and the DCAC. Alternatively, current can flow from the DC-AC converter on the same busbar between the motor and the DC-AC converter.

At step 1206, the capacitor is discharged. For example, in regenerative braking mode, rheostatic braking mode, or a combination of the two modes, the energy stored in the battery can drain to the positive rail. The current can then be fed to the braking resistor.

At 1208, since the contactor is closed, current flows into the braking resistor and is dissipated as heat. For example, a braking resistor can be connected in series with contactors connected in parallel with each other. At least one of the contactors is closed and passes electric current through the braking resistor to the positive rail. Current from the positive rail does not pass through the diodes due to the forward bias voltage in them. In this embodiment, the diodes can be oriented so as to prevent the flow of current in a given leg of the circuit. Alternatively, another type of semiconductor switch can be used, such as an IGBT, which allows current to pass through the component in both directions.

At 1210, current flows through the semiconductor switches. For example, modulating, or opening and closing, semiconductor switches allow smaller discrete amounts of electric current to pass through the braking resistance. If the current is too high for one semiconductor switch, then another semiconductor switch can be installed to carry the current, at least for some time. For example, one semiconductor switch may carry current a third of the time, a second semiconductor switch another third of the time, and a third semiconductor switch may carry current the remaining third of the time. Such a change in the activity of the keys allows for continuous control of the braking of the mechanized system. The duty cycles of each semiconductor switch determine how long the current will be allowed to flow through the braking resistor. The longer the operating cycle, the longer the time during which the semiconductor key is closed and passes current. The use of solid-state switches in combination with brake resistors and contactor switches reduces sparking, wear and tear of discrete components, as well as a reduction in the number of moving parts, and therefore reduces production complexity and costs. In regenerative braking, dynamic braking, or a combination of the two, since the contactors are closed, other power sources can be bypassed. Accordingly, the current flows through the negative bus of the drive system to the capacitor.

At 1212, current is applied to the capacitor. For example, current can flow through the negative bus. The negative rail is connected to the capacitor pole that is not connected to the positive rail. The current is supplied on the negative bus through the connection point of the capacitor to the DC-AC converter.

At 1214, current flows to the DC-AC converter on the negative rail. For example, the negative terminal of a DC-AC converter can be connected to the negative rail. 10 043071 The DC-AC converter can convert the direct current into the alternating current required by the electric motor in regenerative braking, dynamic braking or a combination of the two.

Current flows from the DC-AC converter to the motor.

At 1216, current is supplied to the motor. For example, current can be drawn from the DC-AC converter through another negative rail. Alternatively, the current can flow through the same negative rail that the rest of the circuit is connected to. In regenerative braking, dynamic braking, or a combination of the two, the electric motor is the source of power for the drive system. In this mode, the system can work as required, providing controlled braking and smooth deceleration.

In FIG. 13 shows an example of a method for regenerative braking, dynamic braking, or a combination thereof in the drive system illustrated in FIG. 9. In step 1302, the regenerated electrical power comes from the motor. For example, an electric motor can act as a power source for a drive system. The electric motor can work as a generator, giving off energy previously taken from other sources of electricity, such as batteries. The current from the electric motor is supplied to the DC-AC converter. The incoming current can be alternating (AC). Current can flow to the DC-AC converter through the positive rail located between the motor and the DC-AC converter. The DC-AC converter can convert alternating current to direct current (DC).

At 1304, current flows from the DC-AC converter through another positive rail to the capacitor. For example, the current may flow between the DC-AC converter and the capacitor on a different positive bus than the bus between the motor and the DCAC. Alternatively, current can flow from the DC-AC converter on the same busbar between the motor and the DC-AC converter.

At step 1306, the capacitor is discharged. For example, in regenerative braking mode, rheostatic braking mode, or a combination of the two modes, the energy stored in the battery can drain to the positive rail. The current can then be fed to the braking resistors.

At 1308, since the contactor is closed, current flows into the brake resistors and is dissipated as heat. For example, braking resistors can be connected in series with contactors connected in parallel with each other. At least one of the contactors is closed and passes electric current through the braking resistor to the positive rail. Current may not be allowed to flow in the positive rail through the diodes due to the forward bias voltage in them. In this embodiment, the diodes can be oriented so as to prevent the flow of current in a given leg of the circuit. Alternatively, another type of semiconductor switch can be used, such as an IGBT, which allows current to flow in both directions. The current passes through the resistive arms of the circuit, connected in parallel with each other, in an inductor.

At 1310, current flows through the inductors. For example, inductors can be connected in parallel to each other and connected in series to the resistive arms. The energy stored in the inductors can be released in regenerative braking, dynamic braking or a combination of the two. Current can also flow along the positive rail from inductors to semiconductor switches.

At 1312, current flows through the semiconductor switches. For example, modulating, or opening and closing, semiconductor switches allow smaller discrete amounts of electric current to pass through the braking resistance. If the current is too high for one semiconductor switch, then another semiconductor switch can be installed to carry the current, at least for some time. For example, one semiconductor switch may carry current a third of the time, a second semiconductor switch another third of the time, and a third semiconductor switch may carry current the remaining third of the time. Such a change in the activity of the keys allows for continuous control of the braking of the mechanized system. The duty cycles of each semiconductor switch determine how long the current will be allowed to flow through the braking resistor. The longer the operating cycle, the longer the time during which the semiconductor switch is closed and withstands current. The use of solid-state switches in combination with brake resistors and contactor switches reduces sparking, wear and tear of discrete components, as well as a reduction in the number of moving parts, and therefore reduces production complexity and costs. In regenerative braking, dynamic braking, or a combination of the two, since the contactors are closed, other power sources can be bypassed. Accordingly, the current flows through the negative bus of the drive system to the capacitor.

At 1314, current is supplied to the capacitor. Current flows through the negative bus. For example, the negative rail may be connected to a capacitor pole that is not connected to the positive rail. The current is supplied on the negative bus through the connection point of the capacitor to the DC-AC converter.

At 1316, current flows to the DC-AC converter on the negative rail. For example, the negative terminal of a DC-AC converter can be connected to the negative rail. The DC-AC converter can convert the DC to AC needed by the motor in regenerative braking, dynamic braking, or a combination of the two.

Current flows from the DC-AC converter to the motor.

At 1318, current is supplied to the motor. For example, current can be drawn from the DC-AC converter through another negative rail. Alternatively, the current can flow through the same negative rail that the rest of the circuit is connected to. In regenerative braking, dynamic braking, or a combination of the two, the electric motor is the source of power for the drive system. In this mode, the system can work as required, providing controlled braking and smooth deceleration.

In one or more embodiments, a drive system is provided that may include resistive circuit legs connected to and between (a) a converter that converts electrical current for a motorized system motor and (b) a source of electrical current to power the motor.

Each branch of the circuit may contain a braking resistor connected to the converter. Each leg of the circuit may include a contactor connected to a braking resistor such that the braking resistor is located between the converter and the contactor and a first semiconductor switch connected to the contactor such that the contactor is located between the first semiconductor switch and the braking resistor. In regenerative braking mode, dynamic braking mode, or a combination of these two modes, regenerative braking mode and dynamic braking mode, the regenerative electric current from the motor can be transferred to the braking resistor and dissipated as heat.

Alternatively, each contactor may be configured to be individually controlled to switch between (a) an open state, in which the corresponding braking resistor connected to the contactor is disconnected from the corresponding circuit node, and (b) a closed state, in which the braking resistance corresponding to this contactor and connected to it is connected to the corresponding contactor assembly.

Alternatively, each braking resistor may be configured to dissipate at least a portion of the regenerated electric current from the motor as heat when the respective contactor is in the closed state. Alternatively, each braking resistor may be configured to dissipate at least a portion of the regenerated electric current from the motor as heat when the respective first semiconductor switch is in the closed state. Alternatively, each contactor may be configured to allow at least a portion of the regenerated current from the motor to flow through the capacitor when the contactor is in the open state. Alternatively, (a) one or more diodes or (b) a second semiconductor switch may be connected in parallel to each other, as well as contactors and braking resistors, between the electric current source and the converter.

Alternatively, the electrical current source may be one or more of the following: a conductor rail, a catenary, or an electrical energy storage device. Alternatively, (a) one or more inductors, (b) one or more diodes or second semiconductor switches, (c) contactors, and (d) braking resistors may be connected to the converter in parallel with the alternator and rectifier.

In yet another aspect of the present invention, a drive system is provided that may include a brake resistor connected to a converter that converts electrical current to a motor of a mechanized system, as well as several circuit legs that are connected to the brake resistor in parallel with each other. Each leg of the circuit may include a first semiconductor switch connected to a contactor such that the contactor is located between the first semiconductor switch and the braking resistor. In the regenerative or rheostatic braking mode of the motorized system, the regenerative energy from the motor of the motorized system can be transferred to the brake resistor and dissipated as heat, depending on whether (a) the contactor or (b) the first semiconductor switch is closed.

Alternatively, contactors may be connected in parallel to each other between an off-board electrical current source and a braking resistor. Alternatively, one or more inductors can be connected in parallel with each other, as well as with contactors and braking resistors, between the electric current source and the converter. As an option,

- 12 043071 (a) one or more diodes or (b) a second semiconductor switch are connected in parallel with each other, as well as with contactors and braking resistors, between the electric current source and the converter.

Alternatively, the electrical current source may be one or more of the following: a conductor rail, a catenary, or an electrical energy storage device. Alternatively, (a) inductors, (b) one or more diodes or second semiconductor switches, (c) contactors, and (d) braking resistors may be connected to the converter in parallel with the alternator and rectifier.

Alternatively, a capacitor can be connected to the converter in parallel with the alternator and the rectifier.

In one or more embodiments, a system is provided that may include two or more inductors, one or more first semiconductor switches, and one or more second semiconductor switches. Each inductor may be located on board the mechanized system and optionally connected to an off-board power source as well as a converter that converts the electrical current to the motor of the mechanized system. In addition, each inductor may be connected to a circuit node located between the cathode of the first semiconductor switch of one or more first semiconductor switches and (a) the anode of a diode or (b) the emitter of the second semiconductor switch of one or more second semiconductor switches. Both the anode and the emitter can be connected to the converter, with contactors connected in parallel to each other between the source of the first electric current and the converter. Also, the anode or emitter can be connected to brake resistors connected in parallel to each other, with each brake resistor connected in series with a separate contactor between this contactor and the converter. Also, each anode may be connected to a first semiconductor switch connected to a contactor such that the contactor is located between the first semiconductor switch and the brake resistors. In the regenerative braking mode of the mechanized system, the energy recovered from the electric motor can be transferred to the braking resistor and dissipated as heat, depending on which of the contactors or the first semiconductor switches are closed.

Alternatively, two or more inductors and (a) diodes or (b) a second semiconductor switch may be connected in parallel with contactors and braking resistors between the electrical current source and the converter. Alternatively, the electrical current source may be one or more of the following: a contact rail, a catenary, or an electrical energy storage device. Alternatively, (a) two or more inductors, (b) diodes or a second semiconductor switch, (c) contactors, and (d) braking resistors may be connected to the converter in parallel with the alternator and rectifier.

Alternatively, a capacitor can be connected to the converter in parallel with the alternator and the rectifier.

Expressions in the singular and expressions such as one, one of, or the like also include plural meanings unless the context clearly indicates otherwise. Optional or Optional means that the event or circumstance described below may or may not occur, and that the description includes cases in which the event occurs as well as cases in which it does not occur. Terms indicating approximate values in the present description and in the claims can be used as modifiers of quantitative expressions, the meaning of which can be changed without changing the main function associated with them. Accordingly, the meaning modified by such a term, or terms such as about, approximately, and substantially, is not limited to the exact meaning given. In at least some cases, terms indicating approximate values may correspond to the accuracy of instruments for measuring these values. As used herein, in the specification and in the claims, range restrictions may be combined and/or used interchangeably, and such ranges may be definable and include all subranges contained therein, unless the context or wording indicates otherwise.

This document uses specific examples. They are used to describe options for implementation, including the best (in the opinion of the authors) option for its implementation, as well as to enable its practical application by specialists in this field of technology, including the creation and use of any devices or systems, or the implementation of any methods included in this inventions. The scope of the present invention is defined by the claims and may include other examples as may be found by those skilled in the art. All such additional examples fall within the scope of the claims if they have structural elements that do not differ from the literal description in the claims, or if they include equivalent structural elements with minor differences from the literal description in the claims.

Claims (5)

1. A drive system comprising: at least one resistive circuit arm connected to (a) a converter that converts the first electrical current for the electric motor, and (b) a source of the first electric current for powering the electric motor and located between them, while the specified at least one resistive circuit arm contains: a brake resistor connected to the converter and a contactor connected in series with the brake resistor so that the brake resistor is located between the converter and the contactor; the first semiconductor switch connected to the specified at least one resistive circuit arm, and the diode and/or the second semiconductor switch connected in parallel with the specified at least one resistive circuit arm and electrically connected to the specified converter, while in the mode of regenerative braking, rheostatic braking or a combination of the two modes, the contactor, the first semiconductor switch and the diode and/or the second semiconductor switch are controlled to supply at least a portion of the regenerated electric current from the motor to the braking resistor to control braking by the motor. 2. The system of claim 1, wherein the contactor is individually controllable to switch between (a) an open state, in which the corresponding braking resistor connected to the contactor is disconnected from the corresponding circuit node, and (b) a closed state, in which a braking resistor corresponding to and connected to this contactor is connected to the corresponding circuit node, while said corresponding circuit node is located between the contactor and the first semiconductor switch. 3. The system of claim 2, wherein the braking resistor is configured to dissipate at least a portion of the regenerated electric current from the motor as heat when the respective contactor is in the closed state. 4. The system of claim 2, wherein the contactor is configured to allow at least a portion of regenerated electric current from the motor to pass through the capacitor when the contactor is in the open state, the capacitor being located between said at least one resistive circuit leg and the converter and connected in parallel with the specified at least one resistive arm of the circuit, the specified diode and/or the second semiconductor switch and the specified converter. 5. The system of claim 1, wherein the braking resistor is configured to dissipate at least a portion of the regenerated electric current from the motor as heat when the corresponding first semiconductor switch is in the closed state.