Detailed description of the invention
The regenerative braking energy absorption device of rail vehicle is a kind of device being applied on rail vehicle, feeds back to the electric energy of power supply grid during for absorbing car braking.
The structural representation of the regenerative braking energy absorption device of the rail vehicle that Fig. 1 provides for the embodiment of the present invention, as it is shown in figure 1, this absorption plant includes voltage detection unit the 10, first control unit 11, multiple buck-boost converter 12 and super capacitor 13.
Voltage detection unit 10, for gathering the output voltage of power supply grid.
Voltage detection unit can adopt voltage sensor, voltmeter or other hardware circuits that can measure voltage to realize, can voltage detection unit be connected in the outlet line of power supply grid, the output voltage of voltage detection unit meeting Real-time Collection power supply grid, voltage detection unit can pass through wirelessly or non-wirelessly mode and be connected with the first control unit, to send the output voltage of collection to first control unit, such as, the output voltage of collection can be sent to first control unit by the communication network of track traffic.
First control unit 11, it is connected with described voltage detection unit 10, and be connected with the power switch pipe in each buck-boost converter 12 respectively, for when judging to know described output voltage more than the first predetermined threshold value, generating voltage down control signals to each power switch pipe, described each voltage down control signals frequency is identical and the first setting phase angle that mutually staggers.
When car braking, the motor working condition of traction electric machine translates into electromotor operating mode, it is electric energy by the changes mechanical energy of car braking, and by this back electrical energy to power supply grid, if the vehicle now not having adjacent operation absorbs this part electric energy, the output voltage of power supply grid will raise rapidly at short notice, and this first predetermined threshold value is with the output voltage of now power supply grid for reference, it is possible to be equal to or slightly less than output voltage now.
This output voltage and the first predetermined threshold value, after receiving the output voltage that voltage detection unit transmits, are compared by the first control unit, when judging this output voltage more than the first predetermined threshold value, generate the voltage down control signals to each power switch pipe.
Multiple buck-boost converters 12, described each buck-boost converter 12 is in parallel, input after the parallel connection of described each buck-boost converter 12 is for being connected with the outlet line of power supply grid, outfan and a super capacitor 13 after the parallel connection of described each buck-boost converter 12 are connected, in described each buck-boost converter 12, each power switch pipe is respectively when receiving described each voltage down control signals, staggered conducting the first set angle successively, to be converted to the charging voltage to described super capacitor 13 by the voltage of power supply grid.
Buck-boost converter is a kind of regulator, the DC voltage change of a kind of amplitude can be become the DC voltage of another kind of amplitude, it is generally the circuit that the elements such as pipe, inductance, electric capacity and resistance that opened the light by power form, wherein, power switch pipe can be insulated gate bipolar transistor (InsulatedGateBipolarTransistor, be called for short IGBT), gate level turn-off thyristor (GateTurn-OffThyristor, be called for short GTO) or other kinds of power switch pipe.
Open the light the angle of flow of pipe by controlling power in buck-boost converter, it may be achieved boosting or buck functionality, its output voltage can might be less that input voltage more than input voltage.
The voltage down control signals that first control unit generates is for driving the signal of power switch pipe on or off in each buck-boost converter, and this control signal is generally the pulse signal of certain frequency, width and amplitude.
So-called angle of flow refers to the electrical angle at a cycle internal power switching tube ON time, such as, assuming that voltage down control signals is a pulse signal, a cycle of this pulse signal is 180 degree, and the high level of pulse signal is 50 degree, low level is 130 degree, when pulse signal is high level, power switch pipe turns on, when pulse signal is low level, power switch pipe turns off, then the angle of flow of power switch pipe is 50 degree.
When the angle of flow of power switch pipe is in a certain scope, the output voltage of buck-boost converter is smaller than input voltage, namely realizes buck functionality, and the first set angle in the present embodiment is the angle of flow within the scope of this.Further, when the angle of flow of power switch pipe is within the scope of another, the output voltage of buck-boost converter, also greater than input voltage, namely realizes boost function.
Scope for realizing boosting or buck power switching tube angle of flow is determined according to concrete circuit structure.
In the present embodiment, the frequency of each control signal is identical, but stagger the first setting phase angle mutually, namely the arrival moment of the rising edge of the high level in each voltage down control signals is separated by the first setting phase angle, and the rising edge arrival moment of high level is different, the turn-on instant of each power switch pipe is also just different, therefore, each power switch pipe is under the driving of each control signal, mutually stagger and alternate conduction the first set angle, the voltage of power supply grid is converted to the charging voltage to super capacitor, absorbs, by super capacitor, the electric energy that storage car braking produces.
As shown from the above technical solution, this regenerative braking energy absorption device, it is provided with multiple buck-boost converter, when vehicle is in on-position, control power switch pipe in each buck-boost converter by the first control unit mutually to stagger alternate conduction, power supply grid voltage is converted to the charging voltage to super capacitor by each buck-boost converter respectively, for the control mode that a kind of crisscross parallel runs, the peak value of each buck-boost converter output voltage is interlaced, each output voltage be overlapped mutually after the fluctuating margin of voltage little, stable charging voltage can be provided for super capacitor, therefore, the service life of super capacitor can be improved, and, due to the power switch pipe alternate conduction in each buck-boost converter, each power switch pipe current stress and heat effect can be reduced accordingly, improve the reliability of whole plant running.
The structural representation of the regenerative braking energy absorption device of the rail vehicle that Fig. 2 provides for another embodiment of the present invention, on the basis of above-described embodiment, further, as shown in Figure 2, in this regenerative braking energy absorption device, it is also possible to include the second control unit 14.
Second control unit 14, it is connected with described voltage detection unit 10, and be connected with power switch pipe in described each buck-boost converter 12 respectively, for when judging to know described output voltage less than the second predetermined threshold value, generate the voltage up control signal to each power switch pipe, described each voltage up control signal frequency is identical, and the second setting phase angle that mutually staggers;
In described each buck-boost converter 12, each power switch pipe is respectively when receiving described each voltage up control signal, successively staggered conducting the second set angle, so that the voltage at super capacitor 13 two ends to be changed the output voltage of power supply grid.
When vehicle is when just starting, or due to the increase of vehicle load, during the states such as vehicle driving up operation, required traction power is bigger, now, vehicle needs from the properly functioning bigger electric energy of electrical network short time internal absorptance, and the output voltage of power supply grid will reduce rapidly at short notice, this second predetermined threshold value is with the output voltage of now power supply grid for reference, it is possible to be equal to or slightly greater than output voltage now.
In the present embodiment, second control unit is further set, second control unit is after receiving the output voltage that voltage detection unit transmits, this output voltage and the second predetermined threshold value are compared, when judging this output voltage less than the second predetermined threshold value, generate the voltage up control signal to each power switch pipe.
This voltage up control signal is for driving the signal of power switch pipe on or off in buck-boost converter, and each voltage up control signal frequency is identical, stagger the second setting phase angle mutually, each power switch pipe is under the driving of each voltage up control signal, mutually stagger and alternate conduction the second set angle, now, each buck-boost converter can realize boost function, its output voltage is more than input voltage, namely the voltage at super capacitor two ends is converted to the output voltage of power supply grid, electric energy is exported to power supply grid by super capacitor, improve the output voltage of power supply grid, to ensure that vehicle normally starts or high-power operation.
Due to the peak value of the staggered output voltage of each buck-boost converter, after each output voltage is overlapped mutually, the fluctuating margin of the voltage feeding back to power supply grid can be reduced, improve the quality of power supply grid output voltage, reduce the pollution to power supply grid.
Further, as in figure 2 it is shown, in this regenerative braking energy absorption device, a reactor 15 of connecting respectively in the branch road at described each buck-boost converter 12 place.
By current-limiting reactor in the branch road at buck-boost converter place, can the short-circuit impedance of increasing circuit, short circuit current in limiting circuit, and, when being short-circuited, owing to the voltage on reactor lands relatively big, so the effect of the output voltage maintaining supply voltage outlet line can be played, reduce the fluctuating margin of power supply grid output voltage further.
Further, in the present embodiment, owing to each buck-boost converter adopts the control method of crisscross parallel, the current stress that each reactor bears reduces accordingly, therefore, can reduce the inductance value of each reactor, thus reducing size and the volume of required reactor, can effectively reduce the volume and weight of whole device.
In another embodiment, this brake unit also includes chopper.
Described chopper connection is arranged between input and the outlet line of power supply grid after described each buck-boost converter parallel connection, for when the electric current of the input after described each buck-boost converter parallel connection is more than when setting threshold value, disconnecting the connection line between input and the outlet line of power supply grid after described each buck-boost converter parallel connection.
When the circuit of this device is short-circuited fault or during because of other faults, current value when being likely to result in the electric current of the input after flowing through each buck-boost converter parallel connection more than normal operation, if now continuing to run with this device, wherein each buck-boost converter and super capacitor can be damaged, therefore, in the present embodiment, chopper is further set, more than setting threshold value, (this flows through the current value of input as reference to the electric current of the input after flowing through each buck-boost converter parallel connection when setting threshold value with normal operation, after this setting threshold value is determined, select suitable types chopper) time, chopper can disconnect the connection line between input and the outlet line of power supply grid after each buck-boost converter parallel connection automatically, make this device out of service, so that this device is protected.
The embodiment of the present invention additionally provides a kind of rail vehicle, including pantograph, described pantograph is for contacting with the outlet line of power supply grid, being provided with the regenerative braking energy absorption device that the embodiment of the present invention provides on described vehicle, in described regenerative braking energy absorption device, the input after each buck-boost converter parallel connection is connected with the outlet line of power supply grid by described pantograph.
The roof of rail vehicle is provided with pantograph, is contacted with the outlet line of power supply grid by pantograph, the electric energy of power supply grid to be introduced this energy absorption device.
In this rail vehicle, it is provided with the absorption plant that the embodiment of the present invention provides, when vehicle is in on-position, the voltage of power supply grid is converted to the charging voltage to super capacitor, absorb storage car braking by super capacitor and feed back to the electric energy of power supply grid, this absorption plant can provide stable charging voltage for super capacitor, therefore, the service life of super capacitor can be improved, and, due to the power switch pipe alternate conduction in each buck-boost converter, each power switch pipe current stress and heat effect can be reduced accordingly, improve the reliability of whole plant running.
Last it is noted that various embodiments above is only in order to illustrate technical scheme, it is not intended to limit;Although the present invention being described in detail with reference to foregoing embodiments, it will be understood by those within the art that: the technical scheme described in foregoing embodiments still can be modified by it, or wherein some or all of technical characteristic is carried out equivalent replacement;And these amendments or replacement, do not make the essence of appropriate technical solution depart from the scope of various embodiments of the present invention technical scheme.