CN104494457B - A current source type plug-in hybrid electric vehicle energy transmission drive device and method - Google Patents

Abstract

The invention discloses a current source type plug-in hybrid electric vehicle energy transmission driving device and method. Both the current source type rectifier and the current source type inverter adopt magnetic field oriented control; in the current source type rectifier, according to the engine/generator set Torque reference value, direct axis current reference value, actual speed, voltage, current measurement value to generate rectifier modulation factor and control delay angle; in current source inverter, according to drive motor speed reference value, DC current reference value, actual Speed, voltage, and current measurements generate inverter modulation factors and control delay angles.

Description

A current source type plug-in hybrid electric vehicle energy transmission drive device and method

technical field

The invention relates to a current source type plug-in hybrid electric vehicle energy transmission drive device and method, belonging to the field of plug-in hybrid electric vehicles.

Background technique

With the increasing emission problems of fuel vehicles and the reduction of fossil fuels in the world, electric vehicles and hybrid vehicles have attracted widespread attention. Hybrid vehicles based on engines and motors have become the most potential option for the next generation of new energy vehicles. Hybrids offer better fuel economy, longer operating mileage, and the convenience of refueling the car. Because the structure and control strategy of the traditional two-level voltage source inverter are relatively simple, the voltage source inverter is widely used. Today, the vast majority of electric vehicles and hybrid vehicles use voltage source inverters as electric drives.

Taking a cascaded hybrid electric vehicle based on a voltage source inverter as an example, the engine drives a generator to generate electricity, and the traction motor and battery are connected in parallel through a power converter and connected to the DC bus. This topology has the following disadvantages: 1. If the DC bus uses electrolytic capacitors, its reliability is relatively low. If the DC bus uses film capacitors, the cost is relatively high. 2. The dv/dt of the two-level voltage source inverter is relatively high, which may cause electromagnetic interference, insulation and leakage current problems on the bearing. If a multi-level voltage source inverter is used, the number of switching devices in the system will increase, and the modulation strategy will be more complicated. 3. The voltage source inverter does not allow the upper and lower bridge arms to be turned on at the same time, so it does not have short-circuit fault tolerance. 4. The voltage source inverter only has the ability to step down the voltage, and in order to achieve a wide speed range of the motor system, the motor must be controlled by field weakening.

In order to improve the above problems of the voltage source inverter of hybrid electric vehicles, many new inverter structures have been proposed at home and abroad, mainly focusing on two aspects: soft switching technology and multi-level inverter. In terms of soft switching technology, through the use of auxiliary circuits, the main switching devices of the inverter can achieve zero-voltage or zero-current switching, which can effectively reduce switching losses and electromagnetic interference. Multi-level inverters generate multiple voltage levels through clamping, flying capacitors, and cascading, which improves the harmonic performance of the inverter output voltage and reduces dv/dt. However, the above two technologies both use DC capacitors as energy storage elements on the DC bus, and there are still problems of reliability and cost design of the DC bus capacitor. Moreover, the output voltage amplitude of the voltage source inverter is always lower than the DC bus voltage, and the soft switching and multilevel inverter-fed motor systems still have the problem of field weakening and speed expansion.

Contents of the invention

Purpose of the invention: The present invention proposes a current source type plug-in hybrid electric vehicle energy transmission driving device and method, so that the input side current of the current source type rectifier and the current source type inverter is stable and basically has no fluctuations, and allows the upper and lower bridges The arm device is straight through, and the short-circuit current fault tolerance is improved.

Technical solution: The technical solution adopted in the present invention is a current source type plug-in hybrid electric vehicle energy transmission driving device, including a storage battery, which is connected to the input terminal of the voltage-type full-bridge converter, and the output of the voltage-type full-bridge converter connected to the primary coil of the transformer, and the two secondary coils of the transformer are respectively connected to the input terminals of the first current source full-bridge converter and the second current source full bridge converter, and the current source rectifier passes through the first direct current The flow bus inductance is connected to the output end of the first current source type full-bridge converter, the generator is connected to the output end of the current source type rectifier through the first LC filter, and the current source type inverter is connected to the first current source type inverter through the second DC bus inductance. The output terminals of the second current source type full bridge converter are connected, and the output terminals of the current source type inverter are connected to the motor through the second LC filter.

Preferably, the transformer is a three-port high-frequency transformer.

A control method for an energy transmission drive device of a current source plug-in hybrid electric vehicle. Both the current source rectifier and the current source inverter adopt field-oriented control; in the current source rectifier, according to the engine/generator set torque reference value, direct axis current reference value, actual rotational speed, voltage, and current measurement value to generate rectifier modulation factor _ma1 and control delay angle α ₁ ; in the current source inverter, according to the driving motor speed reference value, DC current reference value, Actual speed, voltage, and current measurements generate inverter modulation factors and control delay angles.

Preferably, the calculation _of the current vector amplitude modulation factor _ma1 of the control current source type rectifier and the control delay angle α1 includes the following steps:

Calculate and obtain the actual torque T of the generator according to the actual a and b phase currents i _a1 and i _b1 of the generator and the a and b phase voltages u _a1 and u _b1 ;

The torque reference value T ^* and the actual torque T pass through the torque controller to generate the generator q-axis current reference value

The current Parker transformation module transforms the actual current of the generator into q-axis current i _q1 and d-axis current i _d1 , and the voltage Parker transformation module transforms the actual generator voltage into q-axis voltage u _q1 and d-axis voltage u _d1 ;

The capacitor compensation current module obtains the q-axis capacitor compensation current i _qc1 and the d-axis capacitor compensation current i _dc1 according to the generator's actual q-axis current i _q1 , d-axis current i _d1 , q-axis voltage u _q1 , and d-axis voltage u _d1 ;

by the generator q-axis current reference value Subtract it from the q-axis capacitor compensation current i _qc1 to obtain the q-axis rectifier current reference value

d-axis current reference value by generator Subtract it from the d-axis capacitor compensation current i _dc1 to obtain the d-axis rectifier current reference value

According to the q-axis inverter current reference value and d-axis inverter current reference The current vector amplitude modulation factor _ma1 and the control delay angle α ₁ for controlling the current source rectifier are obtained by the current vector generation module.

Preferably, the calculation of obtaining the current vector amplitude modulation factor _ma2 of the control current source type inverter and the control delay angle _α2 includes the following steps:

Convert the actual phase a and b currents i _a2 and i _b2 of the motor into q-axis current i _q2 and d-axis current i _d2 , and the voltage parker conversion module converts the actual voltage u _a2 and u _b2 of the motor into q-axis voltage u _q2 and d-axis Voltage u _d2 ;

The capacitor compensation current module obtains the q-axis capacitor compensation current i _qc2 and the d-axis capacitor compensation current i _dc2 according to the motor's actual q-axis current i _q2 , d-axis current i _d2 , q-axis voltage u _q2 , and d-axis voltage u _d2 ;

By the motor q-axis current reference value Subtract it from the q-axis capacitor compensation current i _qc2 to obtain the q-axis inverter current reference value

by motor d-axis current reference Subtract the d-axis inverter current reference value from the q-axis capacitor compensation current i _qc2

According to the q-axis inverter current reference value and d-axis inverter current reference The current vector amplitude modulation factor _ma2 and the control delay angle α ₂ for controlling the current source inverter are obtained by the current vector generation module.

Beneficial effect: compared with the prior art, the present invention has the following advantages:

(1) Current source rectifiers and current source inverters use inductors for energy storage on the DC bus, without the need for DC bus voltage. Therefore, the DC bus storage element has a long service life and low cost. Since the current source rectifier and the current source inverter have inductance on the DC bus, the upper and lower bridge arm devices are allowed to pass through, and the short circuit current fault tolerance is improved.

(2) The increase of the motor speed makes the counter electromotive force and the terminal voltage of the generator also increase. The current source inverter itself has the ability to pump up the voltage, which can expand the constant torque working range of the hybrid electric vehicle.

(3) The output capacitor on the AC side of the current source inverter can not only assist the commutation between the currents of each phase, but also act as a voltage filter, which can provide a better output voltage waveform and reduce the dv/dt value.

(4) The multi-port DC/DC converter adopts a three-port isolated high-frequency transformer, which realizes the electrical isolation of the battery, engine/generator set, and drive motor, and can easily exchange the battery, engine/generator set, and drive motor. Power for energy management.

(5) Compared with the power frequency transformer isolation scheme, the use of an isolated high frequency transformer reduces the weight and size of the system.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is a control block diagram of the present invention;

Fig. 3 is a control block diagram of a current source rectifier control module;

Fig. 4 is a control block diagram of the current source inverter control module;

Fig. 5 is a schematic diagram of the working mode of the control method of the energy transmission driving device of the current source type plug-in hybrid electric vehicle.

detailed description

Below in conjunction with accompanying drawing and specific embodiment, further illustrate the present invention, should be understood that these embodiments are only for illustrating the present invention and are not intended to limit the scope of the present invention, after having read the present invention, those skilled in the art will understand various aspects of the present invention Modifications in equivalent forms all fall within the scope defined by the appended claims of this application.

As shown in Figure 1, the present invention includes a storage battery 1 with a rated input voltage of 24V, the storage battery 1 is connected to the input terminal of a voltage-type full-bridge converter 2, and the output terminal of the voltage-type full-bridge converter 2 is connected to a three-port high-frequency Primary coil of transformer 3. The turn ratio of the three-port high-frequency transformer 3 is set to 1:10:10, and its two secondary coils are respectively connected to the input terminals of the first current source type full-bridge converter 4 and the second current source type full-bridge converter 5 connected. The current source rectifier 6 is connected to the output end of the first current source full bridge converter 4 through the first DC bus inductor 10 , and the generator 8 is connected to the output end of the current source rectifier 6 through the first LC filter 12 . The current source inverter 7 is connected to the output terminal of the second current source full bridge converter 5 through the second DC bus inductor 11, and the output terminal of the current source inverter 7 is connected to the motor 9 through the second LC filter 13 . Both the generator and motor are rated at 240V. The three-port high-frequency transformer 3 implements power conversion between the voltage-type full-bridge converter 2 , the first current-source type full-bridge converter 4 , and the second current-source type full-bridge converter 5 .

The switching devices in the voltage type full bridge converter 2, the first current source type full bridge converter 4, the second current source type full bridge converter 5, the current source type rectifier 6 and the current source type inverter 7 should have reverse Capability to block voltage, can be insulated gate bipolar transistor (IGBT) and diode in series form. The first DC bus inductor 10 and the second DC bus inductor 11 utilize the characteristics of inductance to keep the current at the input side of the current source rectifier 6 and the current source inverter 7 stable and substantially free of fluctuations. The input side of the generator 8 and the motor 9 needs the first LC filter and the second LC filter to filter the low-order harmonic current and voltage, and assist the current source rectifier 6 and the current source inverter 7 to commutate.

As shown in FIG. 2 , the four IGBT switches in the voltage-type full-bridge converter 2 are simultaneously turned on according to the diagonal switches of the bridge arms, and the upper and lower devices of the same bridge arm are complementary to each other. The trigger pulse 2.11 of the voltage-source full-bridge converter controls the IGBT switch in the voltage-source full-bridge converter 2 with a 50% duty cycle trigger pulse, and the phase of the trigger pulse is In the first current source type full bridge converter control module 2.12, through the DC bus current reference value and the closed-loop control of the actual value of the DC bus current i _dc1 to generate the control phase shift angle of the first current source type full-bridge converter 4 Therefore, the phases of the switching devices in the first current source type full-bridge converter 4 are In the second current source type full-bridge converter control module 2.13, through the DC bus current reference value and the closed-loop control of the actual value of the DC bus current i _dc2 to generate the control phase shift angle of the second current source full-bridge converter module 2.5 Therefore, the phase of the switching device in the second current source type full-bridge converter 5 is In the current source rectifier control module 2.14, according to its input torque reference value T ₁ ^* , direct axis current reference value The actual generator speed n ₁ , the actual generator a, b phase voltage v _a1 , v _b1 , the actual generator a, b phase current i _a1 , i _b1 , the current source rectifier control module 2.14 generates the modulation of the current source rectifier 6 Factor _ma1 and control delay angle α ₁ . In the current source inverter control module 2.15, according to its input motor direct axis current reference value Motor speed reference value Motor actual speed n ₂ , actual motor a, b phase voltage u _a2 , u _b2 , actual motor a, b phase current i _a2 , i _b2 , current source inverter control module 2.15 generates current source inverter 7 Modulation factor _ma2 and control delay angle α ₂ .

Figure 3 shows the internal structure of the current source rectifier control module 2.14, in which the torque calculation module 3.1 calculates the power generation according to the actual a and b phase currents i _a1 and i _b1 of the generator 8 and the a and b phase voltages u _a1 and u _b1 Machine 8 actual torque T. The torque reference value T ^* and the actual torque T pass through the torque controller 3.5 to generate the generator q-axis current reference value The current Parker transformation module 3.2 transforms the actual current of the generator 8 into q-axis current i _q1 and d-axis current i _d1 , and the voltage Parker transformation module 3.3 transforms the actual voltage of the generator 8 into q-axis voltage u _q1 and d-axis voltage u _d1 . The capacitor compensation current module 3.4 obtains the q-axis capacitor compensation current i _qc1 and the d-axis capacitor compensation current i _dc1 according to the actual q-axis current i _q1 , d-axis current i _d1 , q-axis voltage u _q1 , and d-axis voltage u _d1 of the generator 8 . by the generator q-axis current reference value Subtract it from the q-axis capacitor compensation current i _qc1 to obtain the q-axis rectifier current reference value d-axis current reference value by generator Subtract it from the d-axis capacitor compensation current i _dc1 to obtain the d-axis rectifier current reference value According to the q-axis inverter current reference value and d-axis rectifier current reference The current vector amplitude modulation factor _ma1 and the control delay angle α ₁ are obtained by the current vector generation module 3.6.

As shown in Figure 4, the current Parker transformation module 4.1 converts the actual a and b phase currents i _a2 , i _b2 of the motor into the q-axis current i _q2 and the d-axis current i _d2 , and the voltage parker transformation module 4.2 converts the actual motor voltages u _a2 , U _b2 is converted into q-axis voltage u _q2 and d-axis voltage u _d2 . The capacitor compensation current module 4.4 obtains the q-axis capacitor compensation current i _qc2 and the d-axis capacitor compensation current i _dc2 according to the motor's actual q-axis current i _q2 , d-axis current i _d2 , q-axis voltage u _q2 , and d-axis voltage u _d2 . By the motor q-axis current reference value Subtract it from the q-axis capacitor compensation current i _qc2 to obtain the q-axis inverter current reference value by motor d-axis current reference Subtract the d-axis inverter current reference value from the q-axis capacitor compensation current i _qc2 According to the q-axis inverter current reference value and d-axis inverter current reference The current vector amplitude modulation factor _ma2 and the control delay angle α ₂ are obtained by the current vector generation module 4.5.

As shown in Fig. 5, when the hybrid electric vehicle is in the process of starting or accelerating, the system operates in the working mode 1, the functional module 1, that is, the battery and the generator 8 driven by the engine jointly drive the motor 9 to run. When the hybrid vehicle is in the high-speed cruising process, the system operates in the working mode 2, and the generator 8 driven by the engine not only provides energy for the electric motor 9, but also charges the battery. When the hybrid vehicle is braking or decelerating downhill, the system operates in the working mode 3, and the generator 8 driven by the engine and the electric motor 9 are both in the power generation state to charge the storage battery.

Claims (5)

1. a current source type plug-in hybrid vehicle energy transmits driving means, it is characterised in that include storing Battery (1), this accumulator (1) is connected to the input of voltage-type full-bridge converter (2), voltage-type full-bridge The outfan of changer (2) accesses the primary coil of transformator (3), two secondary wire of transformator (3) Circle respectively with the first current source type full-bridge converter (4) and the input of the second current source type full-bridge converter (5) End is connected, and current source type commutator (6) is by the first dc bus inductance (10) and the first current source type The outfan of full-bridge converter (4) connects, and electromotor (8) passes through LC wave filter (12) and an electric current Source type commutator (6) outfan is connected, and current source inverter (7) passes through the second dc bus inductance (11) Being connected with the outfan of the second current source type full-bridge converter (5), current source inverter (7) outfan leads to Cross the 2nd LC wave filter (13) and be connected to motor (9).

Current source type plug-in hybrid vehicle energy the most according to claim 1 transmits driving means, its Being characterised by, described transformator (3) is three port high frequency transformers.

3. current source type plug-in hybrid vehicle energy transmits a control method for driving means, and its feature exists In, current source type commutator and current source inverter all use Field orientable control；At current source type commutator In, survey according to electromotor (8) torque reference value, direct-axis current reference value, actual speed, voltage, electric current Value produces rectifier modulation factor (m_a1) and control delay angle (α₁)；In current source inverter, According to motor (9) speed reference, direct-axis current reference value, actual speed, voltage, current measurement value Produce inverter modulation factor (m_a2) and control delay angle (α₂)。

Current source type plug-in hybrid vehicle energy the most according to claim 3 transmits driving means Control method, it is characterised in that comprise the following steps:

According to electromotor (8) actual a, b phase current (i_a1、i_b1) and a, b phase voltage (u_a1、u_b1) Calculate and obtain electromotor (8) actual torque (T)；

Torque reference value (T^*) and actual torque (T) through torque controller (3.5) generate electromotor q Shaft current reference value

Electromotor (8) actual current is transformed to q shaft current (i by electric current Park Transformation module (3.2)_q1) and D shaft current (i_d1), electromotor (8) virtual voltage is transformed to q axle by voltage Park Transformation module (3.3) Voltage (u_q1) and d shaft voltage (u_d1)；

Capacitance compensation current module (3.4) is according to electromotor (8) actual q shaft current (i_q1), d shaft current (i_d1)、 Q shaft voltage (u_q1), d shaft voltage (u_d1) obtain q axle capacitance compensation electric current (i_qc1) and d axle electric capacity benefit Repay electric current (i_dc1)；

By electromotor q shaft current reference valueWith q axle capacitance compensation electric current (i_qc1) subtract each other, obtain q Axle rectifier current reference value

By electromotor d shaft current reference valueWith d axle capacitance compensation electric current (i_dc1) subtract each other, obtain d Axle inverter current reference value

According to q axle inverter current reference valueWith d axle inverter current reference valueBy Current vector generation module (3.6) obtain control current source type commutator (6) current vector amplitude modulation because of Number (m_a1) and control delay angle (α₁)。

Current source type plug-in hybrid vehicle energy the most according to claim 3 transmits driving means Control method, it is characterised in that comprise the following steps:

By motor (9) actual a, b phase current (i_a2、i_b2) be converted to q shaft current (i_q2) and d axle Electric current (i_d2), voltage Park Transformation module (4.2) is by motor (9) virtual voltage (u_a2、u_b2) turn It is changed to q shaft voltage (u_q2) and d shaft voltage (u_d2)；

Capacitance compensation current module (4.4) is according to motor (9) actual q shaft current (i_q2), d shaft current (i_d2)、 Q shaft voltage (u_q2), d shaft voltage (u_d2) obtain q axle capacitance compensation electric current (i_qc2) and d axle electric capacity benefit Repay electric current (i_dc2)；

By motor q shaft current reference valueWith q axle capacitance compensation electric current (i_qc2) subtract each other, obtain q Axle inverter current reference value

By motor d shaft current reference valueWith q axle capacitance compensation electric current (i_qc2) subtract each other, obtain d Axle inverter current reference value

According to q axle inverter current reference valueWith d axle inverter current reference valueBy electricity Flow vector generation module (4.5) obtains the current vector amplitude modulation factor controlling current source inverter (7) (m_a2) and control delay angle (α₂)。