阅读说明：本技术 基于一体化设计间歇式供电牵引控制器 (Intermittent power supply traction controller based on integrated design ) 是由 单宝钰 刘金晶 宫钰明 于 2021-06-30 设计创作，主要内容包括：本发明公开了一种基于一体化设计间歇式供电牵引控制器,包括：设置于机箱内的CPU板、PWM脉冲板、模拟量输入信号板、数字量输入输出板、故障记录板、网关板和电源板；CPU板用于机箱其他电路板数据采集后处理、牵引系统及DCDC系统算法、逻辑控制功能的实现；模拟量输入信号板用于实时获取采样数据；数字量输入输出板为列车DI/DO信号接收和发送,其还用于控制接触器；故障记录板用于故障信号记录；网关板用于为所述牵引系统/DCDC系统与列车构造通讯网络。本发明解决了牵引控制器两个系统之间配合延时的问题,简化了逻辑的复杂性,提升了系统运行稳定性和系统响应速度,减小了牵引控制器的体积、重量,降低了用户维护成本。(The invention discloses an intermittent power supply traction controller based on integrated design, which comprises: the system comprises a CPU board, a PWM pulse board, an analog input signal board, a digital input/output board, a fault recording board, a gateway board and a power supply board which are arranged in a case; the CPU board is used for data acquisition post-processing of other circuit boards of the case, and realization of algorithms and logic control functions of a traction system and a DCDC system; the analog quantity input signal board is used for acquiring sampling data in real time; the digital quantity input and output board is used for receiving and transmitting DI/DO signals of the train and is also used for controlling the contactor; the fault recording board is used for recording fault signals; the gateway board is used for constructing a communication network for the traction system/DCDC system and the train. The invention solves the problem of the matching delay between two systems of the traction controller, simplifies the logic complexity, improves the system operation stability and the system response speed, reduces the volume and the weight of the traction controller and reduces the user maintenance cost.)

1. An intermittently powered traction controller based on an integrated design, comprising a traction system and a DCDC system, wherein the traction controller comprises: the system comprises a CPU board, a PWM pulse board, an analog input signal board, a digital input/output board, a fault recording board, a gateway board and a power supply board;

the PWM pulse board, the analog input signal board, the digital input/output board, the fault recording board, the gateway board and the power supply board are all connected with the CPU board circuit;

the CPU board is used for realizing the functions of the traction system control algorithm part and the DCDC system algorithm part of the optimization algorithm in the interrupt period of the timer and after data acquisition of other circuit boards in the case;

the PWM pulse board is used for outputting a pulse instruction to an energy storage device/motor load based on the control instruction of the CPU board and feeding back information whether the PWM pulse board is reliably sent to a specified power device to the CPU board;

the analog quantity input signal board is used for acquiring sampling data in real time, and transmitting the sampling data to the CPU board after signal conversion, wherein the sampling data comprises but is not limited to a voltage sensor signal, a motor load speed signal, a motor temperature signal, a brake resistor temperature signal and an energy storage device sensor signal;

the fault recording board is used for recording fault data of the traction controller so as to cooperate with the CPU board to determine whether a fault exists;

the digital quantity input and output board is used for receiving and sending train DI/DO signals and is also used for controlling a contactor and matching with the CPU board to carry out circuit switching of control circuits corresponding to a traction system or a DCDC system respectively;

the gateway board is used for constructing a communication network for the traction system/DCDC system and the train;

the power panel is used for receiving an external power supply and converting the power supply into power supply voltage required by each panel.

2. The intermittently-powered traction controller based on an integrated design according to claim 1, wherein the switching control logic of the traction controller comprises:

s21: and (3) after the train is started, carrying out sampling data processing: the sampling data acquired by the analog input signal board is transmitted to the CPU board after signal conversion, initialization setting is carried out through a main control chip in the CPU board, whether the traction controller has a fault or not is judged by combining fault data recorded in the fault recording board, and self-checking of the system is completed;

s22: if the traction controller is in a normal working state, the CPU board receives a signal that the train is in a power-on area/a power-off area, which is received by the digital quantity input and output board communication interface; when the received signal is that the train is in the electrified area, the CPU board executes the traction system control algorithm part of the optimization algorithm in the interrupt period of the timer; the received signal that the train is in the electrified area is transmitted to the digital quantity input and output board, and then the contactor and the receiving contactor are controlled to be closed and fed back; when the received signal is that the train is in the non-electricity area, the CPU board executes the DCDC control algorithm part of the optimization algorithm in the interrupt period of the timer; transmitting the received signal that the train is in the dead zone to the digital quantity input and output board so as to control the contactor and receive the contactor to close and feed back;

s23: when a train is in a power zone, the traction system is started, the analog quantity signal board processes a sampling signal and transmits the processed sampling signal to the CPU board after receiving an instruction fed back by a contactor, the CPU board executes a traction system control algorithm part of an optimization algorithm in a timer interrupt period, and the PWM pulse board outputs a pulse instruction to an energy storage device/motor load based on the instruction of the CUP board and feeds back information whether the PWM pulse board is reliably sent to a specified power device or not to the CPU board;

s24: when the train is in a neutral area, the DCDC system is started, the digital quantity input and output board receives an instruction fed back by the contactor, the analog quantity signal board processes a sampling signal and then transmits the sampling signal to the CPU board, the CPU board executes a DCDC control algorithm part of an optimization algorithm in a timer interrupt period, and the PWM pulse board outputs a pulse instruction to the energy storage device/motor load based on the instruction of the CUP board and feeds back information whether the PWM pulse is reliably sent to a specified power device or not to the CPU board.

3. The intermittently-powered traction controller based on integrated design according to claim 1, wherein the circuits of the traction controller comprise a main control circuit, a traction control circuit and a DCDC control circuit;

the master control circuit is capable of controlling the traction control circuit and the DCDC control circuit;

one end of the main control circuit is connected with the external power supply, the other end of the main control circuit is connected with the traction control circuit, and the other end of the traction control circuit is respectively connected with a motor load and a brake resistor; the DCDC control circuit is connected with the traction control circuit in parallel, one end of the DCDC control circuit is connected with the main control circuit, and the other end of the DCDC control circuit is connected with the energy storage device.

4. The intermittently-powered traction controller based on integrated design according to claim 3, wherein the main control circuit comprises a filter circuit, a pre-charging loop and a detection circuit;

the filter circuit comprises a direct current reactor L1 and a supporting capacitor FC 1;

the pre-charging loop comprises a main contactor KM11, a charging contactor KM12, a first charging resistor R11 and a second charging resistor R12;

the detection circuit comprises a network voltage sensor ESSV1, a bus current sensor DCSC1 and a bus voltage sensor DCSV 1;

two ends of the network voltage sensor ESSV1 are connected with an external power supply, one end of a direct current FUSE FUSE1 is connected with the external power supply, and the other end of the direct current FUSE FUSE1 is connected with the bus current sensor DCSC1, the main contactor KM11 and the reactor L1 in series; one end of the charging contactor KM12 is connected to the connection position of the bus current sensor DCSC1 and the main contactor KM11, the other end of the charging contactor KM12 is connected to the first charging resistor R11, the second charging resistor R12 is connected in parallel to the first charging resistor R11, and the second charging resistor R12 is connected to the connection position of the main contactor KM11 and the reactor L1; the bus voltage sensor DCSV1 is connected in parallel with a first slow discharge resistor R13 and a second slow discharge resistor R14, one end of the bus voltage sensor DCSV1 is connected with the external power supply, and the other end of the bus voltage sensor DCSV is connected with the reactor L1; the support capacitor FC1 is connected in parallel with the bus voltage sensor DCSV 1.

5. The intermittent power supply traction controller based on integrated design as claimed in claim 3, wherein the traction system control circuit comprises a motor load, a brake resistor, a traction U-phase output current sensor SCU, a traction V-phase output current sensor SCV, a traction W-phase output current sensor SCW, a traction braking chopped-wave phase output current sensor SCB, a first inversion traction bridge arm VT11, a second inversion traction bridge arm VT12, a third inversion traction bridge arm VT13, a fourth inversion traction bridge arm VT14, a first capacitor C11, a second capacitor C12, a third capacitor C13 and a fourth capacitor C14;

the first inverter traction bridge arm VT11, the second inverter traction bridge arm VT12, the third inverter traction bridge arm VT13 and the fourth inverter traction bridge arm VT14 are connected in parallel and are all connected in parallel with the supporting capacitor FC1, and the first capacitor C11 is connected in parallel with the first inverter traction bridge arm VT 11; the second capacitor C12 is connected in parallel with the second inverter traction leg VT 12; the third capacitor C13 is connected in parallel with the third inverter traction leg VT 13; the fourth capacitor C14 is connected in parallel with the fourth inverse traction leg VT 14;

the first inverter traction bridge arm VT11, the second inverter traction bridge arm VT12, the third inverter traction bridge arm VT13 and the traction chopping bridge arm VT14 respectively comprise two first switch tubes S connected in series₁And a second switching tube S₂(ii) a One end of the traction U-phase output current sensor SCU is connected with a U-phase wiring terminal of the motor load, and the other end of the traction U-phase output current sensor SCU is connected with a first switching tube S in the first inversion traction bridge arm VT11₁And a second switching tube S₂A joint; one end of the traction V-phase output current sensor SCV is connected with a V-phase terminal of the motor load, and the other end of the traction V-phase output current sensor SCV is connected with a first switching tube S in the second inversion traction bridge arm VT12₁And a second switching tube S₂A joint; one end of the traction W-phase output current sensor SCW is connected with a W-phase terminal of the motor load, and the other end of the traction W-phase output current sensor SCW is connected with a first switching tube S in the third inverter traction bridge arm VT13₁And a second switching tube S₂The joint of (a); one end of the traction braking chopped-wave phase output current sensor SCB is connected with the BCH terminal of the braking resistor, and the other end of the traction braking chopped-wave phase output current sensor SCB is connected with the second switching tube S in the fourth inverse traction bridge arm VT14₁And a second switching tube S₂The joint of (1).

6. The intermittently-powered traction controller based on integrated design as claimed in claim 4, wherein the DCDC control circuit comprises an energy storage device, a DCDC fuse FU15, a DCDC filter capacitor C16, a DCDC bus voltage sensor SV15, a DCDC output reactor L15, a super capacitor side current sensor SCD1, a DCDC control circuit switch tube VT16, a fifth electric power supplyC15; the DCDC control circuit switch tube VT16 comprises a first switch tube S connected in series₁And a second switching tube S₂；

One end of the fifth capacitor C15 is connected to the supporting capacitor FC1, and the other end is connected to the energy storage device via the supporting capacitor FC1 and the external power supply; the other end of the energy storage device is connected with a DCDC fuse FU 15; the DCDC fuse FU15, the DCDC output reactor L15 and the super capacitor side current sensor SCD1 are connected in series; the DCDC control circuit switch tube VT16 is connected in parallel with the supporting capacitor FC1, and the other end of the super capacitor side current sensor SCD1 is connected to the switch tube S₁And a switching tube S₂The joint of (a); one end of the DCDC filter capacitor C16 is connected with the energy storage device, and the other end of the DCDC filter capacitor C16 is connected with the connection position of the DCDC fuse FU15 and the DCDC output reactor L15; the DCDC bus voltage sensor SV15 is connected in parallel with the DCDC filter capacitor C16.

7. The intermittently-powered traction controller based on integrated design according to claim 2, wherein the DCDC control algorithm part of the timer interrupt period optimization algorithm is:

when the switch S₁When conducting, there is a formula:

in the formula: i.e. i_L(t) is the inductor current; i.e. i_s(t) is a first switching tube S₁The tube is conducting current; r_sonIs a first switch tube S₁Or a second switching tube S₂A resistance when on; l is the value of the stored energy inductance, R_LIs an inductance equivalent resistance; v₁Is the network side voltage, V₂Is the energy storage device voltage; u. of_ceqFor the voltage value, R, of the energy storage means_csConnecting an equivalent resistor in series with the energy storage device; c_eqIs the capacity value of the energy storage device; r_cpConnecting an equivalent resistor in parallel for the energy storage device;

when switching tube S₁When turned off, has the formula

The state average equation in one switching period is obtained by the formulas (1) and (2):

in the formula:<x(t)>_TSthe form represents the average value of the variable x (t) over one switching period; d is a switch tube S₁On duty cycle, Ts is the switching period;

reduce equation (3) to:

according to the volt-second balance of the inductor and the ampere-second balance of the capacitor, the second-order disturbance quantity is neglected, and the method is simplified to obtain:

in the formulaRepresenting that the variable makes small disturbance near the x (t) direct current working point;

subjecting (5) to Laplace transform, such thatObtaining the disturbance of the voltage of the inductive current and the super capacitor end to the duty ratioThe transfer function of (a) is:

wherein R is_m＝R_son+R_LIn the super capacitor of the invention, the equivalent parallel resistance R_cpIf considered large, the above equation is simplified to:

the transfer function of the output voltage to the inductor current is as follows:

in the formula: g_vdIs a transfer function of voltage; g_idAs a transfer function of the current, G_vi(s) is a transfer function of the micro-disturbance, and s is an operator after Laplace transform;

therefore, an inductance current and capacitance voltage double closed-loop control model is established, and closed-loop control of output voltage and current is achieved when the DCDC system supplies power to and charges a traction system.

8. The intermittently-powered traction controller based on integrated design according to claim 2, wherein the traction system control algorithm part of the optimization algorithm in the timer interrupt period is as follows:

s81: the analog quantity signal board detects a three-phase output current value of the traction inverter through a U-phase current sensor SCU, a V-phase electric motor rotating speed sensor stream sensor SCV and a W-phase current sensor SCW, and when the current motor rotating speed is detected, a sampling signal is processed and then transmitted to the CPU board for operation to obtain an actual current value and a rotating speed value;

s82: the traction system control algorithm carries out directional transformation of a rotor magnetic field through three-phase current values and rotating speed signals:

in the formula i_αThe alpha axis current value of the two-phase static coordinate system; i.e. i_βThe beta axis current value of the two-phase static coordinate system; i.e. i_uOutputting a current value for a traction U-phase output current sensor SCU; i.e. i_vThe output current value of a traction V-phase output current sensor SCV; i.e. i_wA traction W-phase output current sensor SCW outputs a current value; i.e. i_dD-axis current value i of two-phase rotating coordinate system_qThe q-axis current value of the two-phase rotating coordinate system is obtained; omega₁The dq axis current value frequency is a two-phase rotating coordinate system;

s83: calculating the voltage value of the current value under the converted two-phase rotating coordinate;

in the formula (I), the compound is shown in the specification,a given value of d-axis voltage of a two-phase rotating coordinate system is obtained;a given value of q-axis voltage of a two-phase rotating coordinate system is obtained;a given value of d-axis current of a two-phase rotating coordinate system is obtained;setting a q-axis current given value of a two-phase rotating coordinate system; k is a motor load coefficient; u. of_dIs the d-axis voltage actual output value u of the two-phase rotating coordinate system_qThe actual output value of the q-axis voltage of the two-phase rotating coordinate system is obtained; delta u_dFor d-axis voltage regulation value, [ delta ] u, of two-phase rotating coordinate system_qA q-axis voltage regulating value of a two-phase rotating coordinate system;

s84: substituting the calculated d-axis voltage value and q-axis voltage value in the rotating coordinate system into an SVPWM space vector modulation algorithm to calculate a duty ratio value required by three-phase output:

wherein, t₁The adjacent action time of the space voltage vector is 1; t is t₂The adjacent action time of the space voltage vector is 2; t is t₀Is the zero vector time; ts is a switching period;the voltage per unit value is a three-phase coordinate system;

s85: and according to the calculated SVPWM modulation space voltage vector action time, the duty ratio of switching tubes of inverter bridge arms VT 1-VT 4 of the traction system is obtained, and a deviation decoupling slip type vector control algorithm is realized to control the motor load to reach the given torque requirement.

Technical Field

The invention relates to the field of rail train traction control, in particular to an intermittent power supply traction controller based on integrated design.

Background

At present, urban rail transit trains operate by external power supplies (such as a contact network, a third rail and ground power supply) according to different line conditions, and are also called as electrified areas to supply power; or an energy storage device (a super capacitor, a super battery and the like) is adopted for supplying power for operation, which is also called as non-electric-area power supply operation; or a hybrid power supply operation mode, also called intermittent power supply, is adopted. Therefore, in order to adapt to the intermittent power supply operation mode, the traction controller internally comprises a pre-charging loop, a filtering loop, a traction system and a DCDC system. When the train runs in an electrified area, the traction system runs through an external power supply device, and the DCDC system is charged at the moment; when the train runs in a dead zone, the traction system converts the super capacitor voltage into power supply to run through the DCDC system.

However, the main circuits and the control circuits of the traction system and the DCDC system of the existing intermittent traction controller respectively and independently operate. The traction controller in this way has large volume and weight, the main circuit is complicated, and the traction system and the DCDC system need independent control systems, which increases the production cost of the traction controller. And when the train operates, the traction system and the DCDC system need to carry out logical coordination of a main circuit contactor and a control algorithm so as to realize operations such as operation in a power supply area, operation in a non-power supply area, switching operation between the power supply area and the non-power supply area, and the like.

Disclosure of Invention

The invention provides an intermittent power supply traction controller based on integrated design, which aims to overcome the defects that the existing intermittent traction controller has larger weight and volume and more complex main circuit, and a traction system and a DCDC system need independent control systems, thereby increasing the production cost of the traction controller; and when the train runs, the traction system and the DCDC system need to be logically matched with a main circuit contactor and a control algorithm, and if the matching is not proper, faults are easily caused, and the stable running of the train is influenced.

In order to achieve the purpose, the technical scheme of the invention is as follows:

an intermittently powered traction controller based on an integrated design, comprising a traction system and a DCDC system, the traction controller comprising: the system comprises a CPU board, a PWM pulse board, an analog input signal board, a digital input/output board, a fault recording board, a gateway board and a power supply board;

the PWM pulse board, the analog input signal board, the digital input/output board, the fault recording board, the gateway board and the power supply board are all connected with the CPU board circuit;

the CPU board is used for realizing the functions of the traction system control algorithm part and the DCDC system algorithm part of the optimization algorithm in the interrupt period of the timer and after data acquisition of other circuit boards in the case;

the PWM pulse board is used for outputting a pulse instruction to an energy storage device/motor load based on the control instruction of the CPU board and feeding back information whether the PWM pulse board is reliably sent to a specified power device to the CPU board;

the analog quantity input signal board is used for acquiring sampling data in real time, and transmitting the sampling data to the CPU board after signal conversion, wherein the sampling data comprises but is not limited to a voltage sensor signal, a motor load speed signal, a motor temperature signal, a brake resistor temperature signal and an energy storage device sensor signal;

the fault recording board is used for recording fault data of the traction controller so as to cooperate with the CPU board to determine whether a fault exists;

the digital quantity input and output board is used for receiving and sending train DI/DO signals and is also used for controlling a contactor and matching with the CPU board to carry out circuit switching of control circuits corresponding to a traction system or a DCDC system respectively;

the gateway board is used for constructing a communication network for the traction system/DCDC system and the train;

the power panel is used for receiving an external power supply and converting the power supply into power supply voltage required by each panel.

Further, the switching control logic of the traction controller comprises:

s21: and (3) after the train is started, carrying out sampling data processing: the sampling data acquired by the analog input signal board is transmitted to the CPU board after signal conversion, initialization setting is carried out through a main control chip in the CPU board, whether the traction controller has a fault or not is judged by combining fault data recorded in the fault recording board, and self-checking of the system is completed;

s22: if the traction controller is in a normal working state, the CPU board receives a signal that the train is in a power-on area/a power-off area, which is received by the digital quantity input and output board communication interface; when the received signal is that the train is in the electrified area, the CPU board executes the traction system control algorithm part of the optimization algorithm in the interrupt period of the timer; the received signal that the train is in the electrified area is transmitted to the digital quantity input and output board, and then the contactor and the receiving contactor are controlled to be closed and fed back; when the received signal is that the train is in the non-electricity area, the CPU board executes the DCDC control algorithm part of the optimization algorithm in the interrupt period of the timer; transmitting the received signal that the train is in the dead zone to the digital quantity input and output board so as to control the contactor and receive the contactor to close and feed back;

s23: when a train is in a power zone, the traction system is started, the analog quantity signal board processes a sampling signal and transmits the processed sampling signal to the CPU board after receiving an instruction fed back by a contactor, the CPU board executes a traction system control algorithm part of an optimization algorithm in a timer interrupt period, and the PWM pulse board outputs a pulse instruction to an energy storage device/motor load based on the instruction of the CUP board and feeds back information whether the PWM pulse board is reliably sent to a specified power device or not to the CPU board;

s24: when the train is in a neutral area, the DCDC system is started, the digital quantity input and output board receives an instruction fed back by the contactor, the analog quantity signal board processes a sampling signal and then transmits the sampling signal to the CPU board, the CPU board executes a DCDC control algorithm part of an optimization algorithm in a timer interrupt period, and the PWM pulse board outputs a pulse instruction to the energy storage device/motor load based on the instruction of the CUP board and feeds back information whether the PWM pulse is reliably sent to a specified power device or not to the CPU board.

Furthermore, the circuit of the traction controller comprises a main control circuit, a traction control circuit and a DCDC control circuit;

the master control circuit is capable of controlling the traction control circuit and the DCDC control circuit;

one end of the main control circuit is connected with the external power supply, the other end of the main control circuit is connected with the traction control circuit, and the other end of the traction control circuit is respectively connected with a motor load and a brake resistor; the DCDC control circuit is connected with the traction control circuit in parallel, one end of the DCDC control circuit is connected with the main control circuit, and the other end of the DCDC control circuit is connected with the energy storage device.

Further, the main control circuit comprises a filter circuit, a pre-charging loop and a detection circuit;

the filter circuit comprises a direct current reactor L1 and a supporting capacitor FC 1;

the pre-charging loop comprises a main contactor KM11, a charging contactor KM12, a first charging resistor R11 and a second charging resistor R12;

the detection circuit comprises a network voltage sensor ESSV1, a bus current sensor DCSC1 and a bus voltage sensor DCSV 1;

two ends of the network voltage sensor ESSV1 are connected with an external power supply, one end of a direct current FUSE FUSE1 is connected with the external power supply, and the other end of the direct current FUSE FUSE1 is connected with the bus current sensor DCSC1, the main contactor KM11 and the reactor L1 in series; one end of the charging contactor KM12 is connected to the connection position of the bus current sensor DCSC1 and the main contactor KM11, the other end of the charging contactor KM12 is connected to the first charging resistor R11, the second charging resistor R12 is connected in parallel to the first charging resistor R11, and the second charging resistor R12 is connected to the connection position of the main contactor KM11 and the reactor L1; the bus voltage sensor DCSV1 is connected in parallel with a first slow discharge resistor R13 and a second slow discharge resistor R14, one end of the bus voltage sensor DCSV1 is connected with the external power supply, and the other end of the bus voltage sensor DCSV is connected with the reactor L1; the support capacitor FC1 is connected in parallel with the bus voltage sensor DCSV 1.

Further, the traction system control circuit comprises a motor load, a brake resistor, a traction U-phase output current sensor SCU, a traction V-phase output current sensor SCV, a traction W-phase output current sensor SCW, a traction braking chopped-phase output current sensor SCB, a first inversion traction bridge arm VT11, a second inversion traction bridge arm VT12, a third inversion traction bridge arm VT13, a fourth inversion traction bridge arm VT14, a first capacitor C11, a second capacitor C12, a third capacitor C13 and a fourth capacitor C14;

the first inverter traction bridge arm VT11, the second inverter traction bridge arm VT12, the third inverter traction bridge arm VT13 and the fourth inverter traction bridge arm VT14 are connected in parallel and are all connected in parallel with the supporting capacitor FC1, and the first capacitor C11 is connected in parallel with the first inverter traction bridge arm VT 11; the second capacitor C12 is connected in parallel with the second inverter traction leg VT 12; the third capacitor C13 is connected in parallel with the third inverter traction leg VT 13; the fourth capacitor C14 is connected in parallel with the fourth inverse traction leg VT 14;

the first inverter traction bridge arm VT11, the second inverter traction bridge arm VT12, the third inverter traction bridge arm VT13 and the traction chopping bridge arm VT14 respectively comprise two first switch tubes S connected in series₁And a second switching tube S₂(ii) a One end of the traction U-phase output current sensor SCU is connected with a U-phase wiring terminal of the motor load, and the other end of the traction U-phase output current sensor SCU is connected with a first switching tube S in the first inversion traction bridge arm VT11₁And a second switching tube S₂A joint; one end of the traction V-phase output current sensor SCV is connected with a V-phase terminal of the motor load, and the other end of the traction V-phase output current sensor SCV is connected with a first switching tube S in the second inversion traction bridge arm VT12₁And a second switching tube S₂A joint; one end of the traction W-phase output current sensor SCW is connected with the W-phase wiring end of the motor load, and the other end of the traction W-phase output current sensor SCW is connected with the third inverterFirst switch tube S in variable traction bridge arm VT13₁And a second switching tube S₂The joint of (a); one end of the traction braking chopped-wave phase output current sensor SCB is connected with the BCH terminal of the braking resistor, and the other end of the traction braking chopped-wave phase output current sensor SCB is connected with the second switching tube S in the fourth inverse traction bridge arm VT14₁And a second switching tube S₂The joint of (1).

Further, the DCDC control circuit comprises an energy storage device, a DCDC fuse FU15, a DCDC filter capacitor C16, a DCDC bus voltage sensor SV15, a DCDC output reactor L15, a super capacitor side current sensor SCD1, a DCDC control circuit switch tube VT16 and a fifth capacitor C15; the DCDC control circuit switch tube VT16 comprises a first switch tube S connected in series₁And a second switching tube S₂；

One end of the fifth capacitor C15 is connected to the supporting capacitor FC1, and the other end is connected to the energy storage device via the supporting capacitor FC1 and the external power supply; the other end of the energy storage device is connected with a DCDC fuse FU 15; the DCDC fuse FU15, the DCDC output reactor L15 and the super capacitor side current sensor SCD1 are connected in series; the DCDC control circuit switch tube VT16 is connected in parallel with the supporting capacitor FC1, and the other end of the super capacitor side current sensor SCD1 is connected to the switch tube S₁And a switching tube S₂The joint of (a); one end of the DCDC filter capacitor C16 is connected with the energy storage device, and the other end of the DCDC filter capacitor C16 is connected with the connection position of the DCDC fuse FU15 and the DCDC output reactor L15; the DCDC bus voltage sensor SV15 is connected in parallel with the DCDC filter capacitor C16.

Further, the DCDC control algorithm part of the optimization algorithm in the timer interrupt period is:

when the switch S₁When conducting, there is a formula:

in the formula: i.e. i_L(t) is the inductor current; i.e. i_s(t) is a first switching tube S₁The tube is conducting current; r_sonIs a first switch tube S₁Or a second switching tube S₂A resistance when on; l is the value of the stored energy inductance, R_LIs an inductance equivalent resistance; v₁Is the network side voltage, V₂Is the energy storage device voltage; u. of_ceqFor the voltage value, R, of the energy storage means_csConnecting an equivalent resistor in series with the energy storage device; c_eqIs the capacity value of the energy storage device; r_cpConnecting an equivalent resistor in parallel for the energy storage device;

when switching tube S₁When turned off, has the formula

The state average equation in one switching period is obtained by the formulas (1) and (2):

in the formula:<x(t)>_TSthe form represents the average value of the variable x (t) over one switching period; d is a switch tube S₁On duty cycle, Ts is the switching period;

reduce equation (3) to:

according to the volt-second balance of the inductor and the ampere-second balance of the capacitor, the second-order disturbance quantity is neglected, and the method is simplified to obtain:

in the formulaRepresenting that the variable makes small disturbance near the x (t) direct current working point;

subjecting (5) to Laplace transform, such thatObtaining the disturbance of the voltage of the inductive current and the super capacitor end to the duty ratioThe transfer function of (a) is:

wherein R is_m＝R_son+R_LIn the super capacitor of the invention, the equivalent parallel resistance R_cpIf considered large, the above equation is simplified to:

the transfer function of the output voltage to the inductor current is as follows:

in the formula: g_vdIs a transfer function of voltage; g_idAs a transfer function of the current, G_vi(s) is a transfer function of the micro-disturbance, and s is an operator after Laplace transform; therefore, an inductance current and capacitance voltage double closed-loop control model is established, and closed-loop control of output voltage and current is achieved when the DCDC system supplies power to and charges a traction system.

Further, the traction system control algorithm part of the optimization algorithm in the timer interrupt period is as follows:

s81: the analog quantity signal board detects a three-phase output current value of the traction inverter through a U-phase current sensor SCU, a V-phase electric motor rotating speed sensor stream sensor SCV and a W-phase current sensor SCW, and when the current motor rotating speed is detected, a sampling signal is processed and then transmitted to the CPU board for operation to obtain an actual current value and a rotating speed value;

s82: the traction system control algorithm carries out directional transformation of a rotor magnetic field through three-phase current values and rotating speed signals:

in the formula i_αThe alpha axis current value of the two-phase static coordinate system; i.e. i_βThe beta axis current value of the two-phase static coordinate system; i.e. i_uOutputting a current value for a traction U-phase output current sensor SCU; i.e. i_vThe output current value of a traction V-phase output current sensor SCV; i.e. i_wA traction W-phase output current sensor SCW outputs a current value; i.e. i_dD-axis current value i of two-phase rotating coordinate system_qThe q-axis current value of the two-phase rotating coordinate system is obtained; omega₁The dq axis current value frequency is a two-phase rotating coordinate system;

s83: calculating the voltage value of the current value under the converted two-phase rotating coordinate;

in the formula (I), the compound is shown in the specification,a given value of d-axis voltage of a two-phase rotating coordinate system is obtained;a given value of q-axis voltage of a two-phase rotating coordinate system is obtained;as two-phase rotation coordinatesIs a d-axis current set value;setting a q-axis current given value of a two-phase rotating coordinate system; k is a motor load coefficient; u. of_dIs the d-axis voltage actual output value u of the two-phase rotating coordinate system_qThe actual output value of the q-axis voltage of the two-phase rotating coordinate system is obtained; delta u_dFor d-axis voltage regulation value, [ delta ] u, of two-phase rotating coordinate system_qA q-axis voltage regulating value of a two-phase rotating coordinate system;

s84: substituting the calculated d-axis voltage value and q-axis voltage value in the rotating coordinate system into an SVPWM space vector modulation algorithm to calculate a duty ratio value required by three-phase output:

wherein, t₁The adjacent action time of the space voltage vector is 1; t is t₂The adjacent action time of the space voltage vector is 2; t is t₀Is the zero vector time; ts is a switching period;the voltage per unit value is a three-phase coordinate system;

s85: and according to the calculated SVPWM modulation space voltage vector action time, the duty ratio of switching tubes of inverter bridge arms VT 1-VT 4 of the traction system is obtained, and a deviation decoupling slip type vector control algorithm is realized to control the motor load to reach the given torque requirement.

Has the advantages that: the invention solves the problem of the matching delay between two systems of the traditional intermittent traction controller by the integrated design mode of the main control circuit of the traction controller, so that the traction system and the DCDC system are not controlled independently, the complexity of logic is simplified, the running stability and the system response speed of the system are improved, the volume, the weight and the purchasing cost of the traction controller are reduced, the number and the types of spare parts of a train are reduced, and the maintenance cost of a user is reduced.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic diagram of a main circuit of an intermittent power supply traction controller based on an integrated design according to the invention;

FIG. 2 is a logic diagram of an intermittent power supply traction controller control algorithm based on an integrated design according to the invention;

FIG. 3 is an equivalent circuit diagram of the DCDC system of the present invention;

FIG. 4 shows a switching tube S according to the present invention₁An equivalent circuit diagram when conducting;

FIG. 5 is a block diagram of a dual closed-loop control model for inductor current and capacitor voltage according to the present invention;

FIG. 6 is a schematic diagram of the positions of VT 11-VT 14 and VT16 in the traction system and the DCDC system of the present invention;

fig. 7 is a schematic diagram of a main circuit of another embodiment of the intermittently powered traction controller based on an integrated design according to the present invention.

Wherein: g_i(s) a current PI controller; g_u(s) a voltage PI controller; d(s), controller delay; 1/K₁Sampling a proportional coefficient of the inductive current, and taking 1/150; 1/K₂And the output voltage sampling proportionality coefficient is 1/200.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The embodiment provides an intermittent power supply traction controller based on integrated design, which comprises a traction system and a DCDC system, and is characterized in that the traction controller comprises: the system comprises a CPU board, a PWM pulse board, an analog input signal board, a digital input/output board, a fault recording board, a gateway board and a power supply board which are arranged in a case; the PWM pulse board, the analog input signal board, the digital input/output board, the fault recording board, the gateway board and the power supply board are all connected with the CPU board through circuits.

The CPU board is used for realizing the functions of the traction system control algorithm part and the DCDC system algorithm part of the optimization algorithm in the interrupt period of the timer and after data acquisition of other circuit boards in the case;

the PWM pulse board is used for outputting a pulse instruction to an energy storage device/motor load based on the control instruction of the CPU board and feeding back information whether the PWM pulse board is reliably sent to a specified power device to the CPU board;

the analog quantity input signal board is used for acquiring sampling data in real time, and transmitting the sampling data to the CPU board after signal conversion, wherein the sampling data comprises but is not limited to a voltage sensor signal, a motor load speed signal, a motor temperature signal, a brake resistor temperature signal and an energy storage device sensor signal; specifically, the analog input signal board is used for receiving a voltage sensor signal, a motor load speed signal, a motor temperature signal, a brake resistor temperature signal, an energy storage device voltage \ current \ temperature \ smoke and fire and other sensor signals;

the digital quantity input and output board is used for receiving and sending train DI/DO signals and is also used for controlling a contactor and matching with the CPU board to carry out circuit switching of control circuits corresponding to a traction system or a DCDC system respectively; the contactors used in this embodiment include a main contactor KM11 and a charging contactor KM 12;

the fault recording board is used for recording fault data of the traction controller so as to cooperate with the CPU board to determine whether a fault exists; recording signals such as voltage \ current and the like at the moment of failure; the gateway board is used for constructing a communication network for the traction system/DCDC system and the train; the power panel is used for receiving an external power supply and converting the external power supply into power supply voltage required by each panel; specifically, the power panel receives an external power supply to convert the external power supply into the power supply voltages of the CPU board, the PWM pulse board, the analog input signal board, the digital input/output board, the fault recording board, the gateway board, and the power panel in the chassis.

Specifically, the traction system algorithm and the DCDC system algorithm are integrated into the same algorithm and stored in a CPU board for operation and control; because the execution control is carried out in the same algorithm, the matching logic of external communication and hardware circuits is reduced, and the integrated control algorithm logic is shown as the attached figure 2 and comprises the following steps: processing data in the same sampling function, performing the same calculation for the sampled data, controlling logic, protecting fault, recording after calculation and executing pulse function output in the same PWM interruption period. The invention integrates a set of control algorithms under the same CPU, and processes sampling, pulse and fault protection operation functions in the same way;

the CPU board, the PWM pulse board, the analog input signal board, the digital input/output board, the fault recording board, the gateway board and the power supply board are all inserted into a back board slot of the same case, and circuit connection and communication are carried out through a back board hardware circuit and a data bus. The system hardware of the embodiment is integrated, so that the size of the chassis is reduced from 84TE to 48 TE.

As shown in fig. 1, the circuit of the traction controller includes a main control circuit, a traction control circuit and a DCDC control circuit; the master control circuit is capable of controlling the traction control circuit and the DCDC control circuit;

one end of the main control circuit is connected with the external power supply, the other end of the main control circuit is connected with the traction control circuit, and the other end of the traction control circuit is respectively connected with a motor load and a brake resistor; the DCDC control circuit is connected with the traction control circuit in parallel, one end of the DCDC control circuit is connected with the main control circuit, and the other end of the DCDC control circuit is connected with the energy storage device.

Specifically, the main control circuit comprises a filter circuit, a pre-charging loop and a detection circuit; the filter circuit comprises a direct current reactor L1 and a supporting capacitor FC 1; the pre-charging loop comprises a main contactor KM11, a charging contactor KM12, a first charging resistor R11 and a second charging resistor R12; the detection circuit comprises a network voltage sensor ESSV1, a bus current sensor DCSC1 and a bus voltage sensor DCSV 1;

two ends of the network voltage sensor ESSV1 are connected with an external power supply, one end of a direct current FUSE FUSE1 is connected with the external power supply, and the other end of the direct current FUSE FUSE1 is connected with the bus current sensor DCSC1, the main contactor KM11 and the reactor L1 in series; one end of the charging contactor KM12 is connected to the connection position of the bus current sensor DCSC1 and the main contactor KM11, the other end of the charging contactor KM12 is connected to the first charging resistor R11, the second charging resistor R12 is connected in parallel to the first charging resistor R11, and the second charging resistor R12 is connected to the connection position of the main contactor KM11 and the reactor L1; the bus voltage sensor DCSV1 is connected in parallel with a first slow discharge resistor R13 and a second slow discharge resistor R14, one end of the bus voltage sensor DCSV1 is connected with the external power supply, and the other end of the bus voltage sensor DCSV is connected with the reactor L1; the support capacitor FC1 is connected in parallel with the bus voltage sensor DCSV 1.

The traction system control circuit comprises a motor load, a brake resistor and a traction U-phase output current sensor SCU; a traction V-phase output current sensor SCV; a traction W-phase output current sensor SCW; a traction braking chopping phase output current sensor SCB; the traction control circuit comprises a first inverter traction bridge arm VT11, a second inverter traction bridge arm VT12, a third inverter traction bridge arm VT13, a fourth inverter traction bridge arm VT14, a first capacitor C11, a second capacitor C12, a third capacitor C13 and a fourth capacitor C14;

the first inverter traction bridge arm VT11, the second inverter traction bridge arm VT12, the third inverter traction bridge arm VT13 and the fourth inverter traction bridge arm VT14 are connected in parallel and are all connected in parallel with the supporting capacitor FC1, and the first capacitor C11 is connected in parallel with the first inverter traction bridge arm VT 11; the second capacitor C12 is connected in parallel with the second inverter traction leg VT 12; the third capacitor C13 is connected in parallel with the third inverter traction leg VT 13; the fourth capacitor C14 is connected in parallel with the fourth inverse traction leg VT 14;

the first inversion traction bridge arm VT11 and the second inversion traction bridge armThe approach bridge arm VT12, the third inverter traction bridge arm VT13 and the traction chopper bridge arm VT14 all comprise a first switch tube S connected in series₁And a second switching tube S₂(ii) a One end of the traction U-phase output current sensor SCU is connected with a U-phase wiring terminal of the motor load, and the other end of the traction U-phase output current sensor SCU is connected with a first switching tube S in the first inversion traction bridge arm VT11₁And a second switching tube S₂A joint; one end of the traction V-phase output current sensor SCV is connected with a V-phase terminal of the motor load, and the other end of the traction V-phase output current sensor SCV is connected with a first switching tube S in the second inversion traction bridge arm VT12₁And a second switching tube S₂A joint; one end of the traction W-phase output current sensor SCW is connected with a W-phase terminal of the motor load, and the other end of the traction W-phase output current sensor SCW is connected with a first switching tube S in the third inverter traction bridge arm VT13₁And a second switching tube S₂The joint of (a); one end of the traction braking chopped-wave phase output current sensor SCB is connected with the BCH terminal of the braking resistor, and the other end of the traction braking chopped-wave phase output current sensor SCB is connected with the second switching tube S in the fourth inverse traction bridge arm VT14₁And a second switching tube S₂The joint of (1). First switch tube S in the present embodiment₁And a second switching tube S₂Insulated Gate Bipolar Transistors (IGBT) are adopted.

In an embodiment of the present invention, the motor load includes a device sharing an external power supply (DC750V) with the DCDC system of the traction controller, taking the existing urban rail project as an example, and includes 3 train-receiving marshalling, two traction cabinets and 2 auxiliary cabinets, wherein the energy storage device in 1 traction cabinet supplies power to other traction cabinet and auxiliary cabinet devices through the DCDC system and the main contactor. FIG. 6 shows the position diagrams of VT 11-VT 14 and VT16 in the traction system and the DCDC system of the present invention.

The DCDC control circuit comprises an energy storage device, a DCDC fuse FU15, a DCDC filter capacitor C16, a DCDC bus voltage sensor SV15, a DCDC output reactor L15, a super capacitor side current sensor SCD1, a DCDC control circuit switch tube VT16 and a fifth capacitor C15;

one end of the fifth capacitor C15 is connected to the supporting capacitor FC1, and the other end is connected to the energy storage device via the supporting capacitor FC1 and the external power supply; the other end of the energy storage device is connected with a DCDC fuse FU 15; the DCDC fuse FU15, the DCDC output reactor L15 and the super capacitor side current sensor SCD1 are connected in series; the DCDC control circuit switching tube VT16 is connected in parallel with the support capacitor FC1 and comprises two Insulated Gate Bipolar Transistors (IGBT) connected in series, and the other end of the super-capacitor side current sensor SCD1 is connected to the connection position of the two Insulated Gate Bipolar Transistors (IGBT); one end of the DCDC filter capacitor C16 is connected with the energy storage device, and the other end of the DCDC filter capacitor C16 is connected with the connection position of the DCDC fuse FU15 and the DCDC output reactor L15; the DCDC bus voltage sensor SV15 is connected in parallel with the DCDC filter capacitor C16.

Specifically, S21: the integrally designed intermittent power supply traction controller is powered on by an external low-voltage direct-current power supply to start a rail train; the sampling data acquired by the analog input signal board is transmitted to the CPU board after signal conversion, initialization setting is carried out through a main control chip in the CPU board, whether the traction controller has a fault or not is judged by combining fault data recorded in the fault recording board, and self-checking of the system is completed;

s22: if the traction controller is in a normal working state, the CPU board receives a signal that the train is in a power-on area/a power-off area, which is received by the digital quantity input and output board communication interface; when the received signal that the train is in the electrified region is received, executing the traction system control algorithm to transmit the received signal that the train is in the electrified region to the digital quantity input and output board so as to control the contactor and the receiving contactor to be closed for feedback; when a signal that the train is in a dead zone is received, executing the DCDC control algorithm to transmit the received signal that the train is in the dead zone to the digital quantity input and output board so as to control a contactor and receive contactor closing feedback; thereby completing the switching between the traction system and the DCDC system;

s23: when a train is in a power zone, the traction system is started, after the digital input and output board receives an instruction fed back by a contactor, the analog signal board processes a sampling signal and transmits the sampling signal to the CPU board, the CPU board sends an instruction for executing a traction system control algorithm, and the PWM pulse board outputs a pulse instruction to an energy storage device/motor load based on the instruction of the CPU board and feeds back information whether the PWM pulse board is reliably sent to a specified power device or not to the CPU board;

1) when the network pressure value monitored by the network pressure sensor ESSV1 is collected by the CPU board through the analog quantity signal board SGN, the closed charging contact KM12 is controlled through the digital quantity input and output board (DI/DO); the supporting capacitor FC1 is charged by the current limiting of the electrons R11/R12; 2) the CPU board detects that the bus voltage reaches a preset value through an analog quantity signal board SGN acquisition bus voltage sensor DCSV1, and controls to close a main contactor KM11 and open a charging contactor KM12 through a digital quantity input/output board (DI/DO); 3) after the CPU board detects the closing feedback of the main contactor through a digital input/output (DI/DO) board, a program executes a charging instruction, and a pulse instruction is sent to VT16 through a PWM pulse board to charge the energy storage device; meanwhile, a program executes traction three-phase output and braking chopping instructions, and pulse instructions are sent to VT 11-VT 14 through a PWM pulse plate; three phases are output to a motor load, and braking chopping is output to a braking resistor.

S24: when a train is in a neutral area, the DCDC system is started, after the digital input and output board receives an instruction fed back by a contactor, the analog signal board processes a sampling signal and transmits the sampling signal to the CPU board, the CPU board sends an instruction for executing a DCDC control algorithm, and the PWM pulse board outputs a pulse instruction to an energy storage device/motor load based on the instruction of the CPU board and feeds back information whether the PWM pulse board is reliably sent to a specified power device or not to the CPU board; the power device comprises a traction system, a DCDC system power switch tube, a driving plate, VT 11-VT 14 and VT 16.

When 1) the CPU board receives a no-cell instruction through a digital input/output (DI/DO) board, the program executes a power supply instruction, and sends a pulse instruction to VT16 through a PWM pulse board; 2) the CPU acquires a bus voltage sensor DCSV1 through an analog quantity signal board (SGN) to detect that the bus voltage reaches a preset value, and controls to close a main contactor KM11 through a digital quantity input/output board (DI/DO); 3) the program executes traction three-phase output and braking chopping instructions, and pulse instructions are sent to VT 11-VT 14 through a PWM pulse plate; the energy storage device supplies power to the outside, and outputs to the motor load through the inverter three-phase, and the brake chopper outputs to the brake resistor.

When the train is in a neutral area, a digital input/output (DI/DO) board is controlled to receive an external operation instruction, an external logic control function is executed in the period of a timer in a DSP chip, and the timer interrupts execution of a DCDC control algorithm; the bus voltage sensor DCSV1 detects the bus voltage U_dcAfter the processed analog input Signal (SGN) board of the control unit is sent to a DSP chip to reach a system set threshold value, a KM11 closing instruction is sent out through a digital input/output (DI/DO) board, and when a bus voltage sensor DCSV1 detects a bus voltage U_dcAfter reaching the set threshold in the algorithm, the timer interrupts the execution of the traction system control algorithm; the train normally runs in the dead zone.

The DCDC control algorithm part of the optimization algorithm in the timer interrupt period comprises the following steps:

DCDC system control scheme adopts S₁、S₂Mode of individual control, S₁、S₂Respectively a switch tube S in a switch tube VT16 of a DCDC system control circuit₁And a switching tube S₂. The running state of the circuit is manually input and controlled by a cab switch. In Buck mode, the control signal controls S₁On-off, S₂Is always off, only D_s2Acting on freewheeling. Similarly, in Boost mode, S₁Is always turned off to control the switch S₂And switching on and off to realize the electric energy output of the super capacitor. The model establishment and analysis methods of the circuit working in Buck and Boost modes are the same, so that the small signal model establishment is only carried out by taking the circuit in Buck mode as an example.

The equivalent circuit of the DCDC system is shown in FIG. 3, where R_LFor equivalent internal resistance, R, of the energy-storing inductor_cs、R_cpRespectively a super capacitor equivalent series resistance and a parallel resistance.

Switch tube S₁Circuit equivalent models at turn-on and turn-off respectivelyAs shown in fig. 4 and 5, it is assumed that the on-resistances of the switching devices are all R_son。

Switch S₁When conducting, there is a formula:

in the formula: i.e. i_L(t) is the inductor current; i.e. i_s(t) is a switching tube S₁The tube is conducting current; r_sonIs a switch tube S₁Or a switching tube S₂A resistance when on; l is the value of the stored energy inductance, R_LIs an inductance equivalent resistance; v₁Is the network side voltage, V₂Is the energy storage device voltage; u. of_ceqFor the voltage value, R, of the energy storage means_csConnecting an equivalent resistor in series with the energy storage device; c_eqIs the capacity value of the energy storage device; r_cpConnecting an equivalent resistor in parallel for the energy storage device;

when switching tube S₁When turned off, has the formula

The state average equation in one switching period is obtained by the formulas (1) and (2):

in the formula:<x(t)>_TSthe form represents the average value of the variable x (t) over one switching period; d is a switch tube S₁On duty cycle, Ts is the switching period;

reduce equation (3) to:

according to the volt-second balance of the inductor and the ampere-second balance of the capacitor, the second-order disturbance quantity is neglected, and the method is simplified to obtain:

in the formulaIndicating that the variable does small perturbation near the x (t) DC operating point.

Subjecting (5) to Laplace transform, such thatObtaining the disturbance of the voltage of the inductive current and the super capacitor end to the duty ratioThe transfer function of (a) is:

wherein R is_m＝R_son+R_LIn the super capacitor of the invention, the equivalent parallel resistance R_cpIf considered large, the above equation is simplified to:

the transfer function of the output voltage to the inductor current is as follows:

in the formula: g_vdIs a transfer function of voltage; g_idAs a transfer function of the current, G_vi(s) is a transfer function of the small perturbation, and s is an operator after Laplace transform.

According to the small signal model analysis, an inductive current and capacitor voltage double closed-loop control model shown in fig. 5 is established to realize closed-loop control of output voltage and current when the DCDC system supplies power to and charges the traction system.

The traction system control algorithm part of the optimization algorithm in the timer interrupt period comprises the following steps:

the algorithm program comprises a vector control algorithm and an SVPWM space vector modulation algorithm. The vector control algorithm adopts an offset-based decoupling slip type vector control algorithm. The specific implementation procedure is as follows.

(1) The analog quantity signal board detects a three-phase output current value of the traction inverter through a U-phase current sensor SCU, a V-phase electric motor rotating speed sensor stream sensor SCV and a W-phase current sensor SCW, and after the current motor rotating speed is detected, a sampling signal is subjected to A/D processing and then sent to a CPU board for operation. And the sampling calculation function in the timer period interruption is used for carrying out operation processing on the digital quantity signal to obtain an actual current value and a rotating speed value.

(2) The traction control algorithm carries out directional transformation of the rotor magnetic field through three-phase current values and rotation speed signals.

Wherein i_αThe alpha axis current value of the two-phase static coordinate system; i.e. i_βThe beta axis current value of the two-phase static coordinate system; i.e. i_uOutputting a current value for a traction U-phase output current sensor SCU; i.e. i_vThe output current value of a traction V-phase output current sensor SCV; i.e. i_wA traction W-phase output current sensor SCW outputs a current value; i.e. i_dD-axis current value i of two-phase rotating coordinate system_qThe q-axis current value of the two-phase rotating coordinate system is obtained; omega₁The dq axis current value frequency is a two-phase rotating coordinate system;

(3) and calculating the voltage value of the current value under the converted two-phase rotation coordinate.

Wherein the content of the first and second substances,a given value of d-axis voltage of a two-phase rotating coordinate system,A given value of q-axis voltage of a two-phase rotating coordinate system is obtained;a given value of d-axis current of a two-phase rotating coordinate system,Setting a q-axis current given value of a two-phase rotating coordinate system; k is a motor load coefficient; u. of_dIs the d-axis voltage actual output value u of the two-phase rotating coordinate system_qThe actual output value of the q-axis voltage of the two-phase rotating coordinate system is obtained; delta u_dFor d-axis voltage regulation value, [ delta ] u, of two-phase rotating coordinate system_qAnd the voltage regulating value is a q-axis voltage regulating value of the two-phase rotating coordinate system.

(4) Substituting the calculated d-axis voltage value and the q-axis voltage value in the rotating coordinate system into an SVPWM space vector modulation algorithm to calculate a duty ratio value required by three-phase output.

Wherein, t₁The adjacent action time of the space voltage vector is 1; t is t₂The adjacent action time of the space voltage vector is 2; t is t₀Is the zero vector time; ts is a switching period;the voltage per unit value is a three-phase coordinate system;

(5) according to the calculated SVPWM modulation space voltage vector action time, the duty ratio of switching tubes of inverter bridge arms VT 1-VT 4 of the traction system can be obtained, a required pulse signal is output, a deviation decoupling slip type vector control algorithm is realized, and the motor load is controlled to meet the requirement of given torque.

In another embodiment of the present invention, the motor load connected to the traction inverter can be expanded to more than two loads by increasing the number of traction inverter legs, and the schematic diagram is shown in fig. 7.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.