CN-121984146-A - Energy efficiency optimization system of auxiliary power unit of pure electric vehicle

CN121984146ACN 121984146 ACN121984146 ACN 121984146ACN-121984146-A

Abstract

The invention relates to the technical field of power supply of auxiliary equipment of electric vehicles, and discloses an energy efficiency optimization system of an auxiliary power unit of a pure electric vehicle, which comprises the following components: the invention relates to a power conversion module, an auxiliary load module, a characteristic sampling module and a compensation control module, wherein the characteristic sampling module controls the power conversion module to send pulse disturbance to a direct current bus in a sampling period before the auxiliary load module is started to enable and a power loop is conducted, and obtains bus current response quantity and voltage change rate, the compensation control module determines a bus real-time capacitance value and a load damping coefficient based on bus current response quantity and voltage change rate inversion and is used for counteracting compensation charges for starting voltage drop, and the power conversion module extracts transient preset energy at load power.

Inventors

Xie Longquan
YANG JIE
ZHANG GANG
LI ZHENBING

Assignees

长沙优来电子科技有限公司

Dates

Publication Date: 20260505
Application Date: 20260403

Claims (10)

1. An energy efficiency optimization system of an auxiliary power unit of a pure electric vehicle, which is characterized by comprising: the power conversion module is connected between the direct current bus and the auxiliary load module; The characteristic sampling module is used for controlling the power conversion module to output a pulse voltage signal to the direct current bus in a pre-conduction sampling period before the auxiliary load module receives the starting signal and the power loop is conducted, and obtaining a current response variable quantity and a bus voltage actual variable rate generated by the response of the direct current bus end to the pulse voltage signal; The compensation control module is used for calculating bus supporting capacity characteristics representing the real-time attenuation state of the direct-current bus end supporting capacitor through a parameter inverse algorithm based on the current response variable quantity and the bus voltage actual variable rate, calculating transient damping characteristics representing the starting resistance offset of the auxiliary load module along with the life cycle evolution, and determining a compensation charge quantity for compensating the starting instant bus voltage drop according to the nonlinear coupling relation between the bus supporting capacity characteristics and the transient damping characteristics; And the power conversion module is used for executing transient electric quantity injection to the direct current bus according to the compensation electric quantity in a preset time window before the auxiliary load module formally executes power extraction so as to offset bus voltage nonlinear dip caused by capacitor aging and load damping offset by utilizing the preset electric quantity of the direct current bus.
2. The energy efficiency optimization system of the auxiliary power unit of the pure electric vehicle according to claim 1, wherein the energy efficiency optimization system further comprises an energy recovery module, the energy recovery module is used for monitoring induced electromotive force generated by an internal winding of the auxiliary load module in a shutdown discharging stage and guiding residual magnetic field potential energy generated by the induced electromotive force to a direct current bus to construct a dynamic energy buffer pool, and the compensation control module is further used for reading available charge stock information in the dynamic energy buffer pool in real time when determining a compensation charge amount and controlling the power conversion module to preferentially call charges in the dynamic energy buffer pool as energy sources for executing transient electric quantity injection so as to schedule the whole energy efficiency of the system through residual energy in a cross-load time domain.
3. The energy efficiency optimization system of the auxiliary power unit of the pure electric vehicle according to claim 1, wherein the compensation control module is used for determining the ratio of the amplitude of the pulse voltage signal to the actual change rate of the bus voltage as a real-time bus capacitance value when calculating the bus support capacity characteristic, and is used for determining the current load loss characteristic parameter of the auxiliary load module according to the integral slope of the current response change quantity in a pre-conduction sampling period when calculating the transient damping characteristic.
4. The energy efficiency optimization system of an auxiliary power unit for a pure electric vehicle according to claim 1, wherein the compensation control module determines the compensation charge amount by following a quantization mapping rule when determining the compensation charge amount : , wherein, In order for the amount of current response change, For the real-time bus capacitance value, To characterize the normalized feedback coefficient of the transient damping characteristic, Is a weight factor determined from the load loss characteristic parameter.
5. The energy efficiency optimization system of the auxiliary power unit of the pure electric vehicle according to claim 1, further comprising a carrier phase control module, wherein the carrier phase control module is used for obtaining a power switch carrier phase of the power conversion module and a driving carrier phase of the auxiliary load module, and enabling a switching tube conduction time of the power conversion module to be complementary with a current extraction time of the auxiliary load module in a time domain through adjusting a sampling trigger period so as to reduce a synthesized ripple current of a direct current bus end.
6. The energy efficiency optimization system of the auxiliary power unit of the pure electric vehicle according to claim 1, wherein the characteristic sampling module comprises a current sensing unit and a differential operation unit, the current sensing unit is used for sampling the current response variation in a pre-conduction sampling period at a frequency not lower than 100kHz, and the differential operation unit is used for extracting step response of an analog voltage signal of a direct-current bus to obtain the actual change rate of the bus voltage.
7. The energy efficiency optimization system of the auxiliary power unit of the pure electric vehicle according to claim 1, wherein the compensation control module is connected with an adaptive parameter correction module, and the adaptive parameter correction module is used for monitoring an actual voltage change track of the direct current bus after the auxiliary load module is started, and comparing a deviation value of the actual voltage change track with a preset reference curve so as to update nonlinear coupling relation characteristics in the compensation control module on line according to the deviation value.
8. The energy efficiency optimization system of the auxiliary power unit of the pure electric vehicle according to claim 1, wherein the system further comprises a priority scheduling module, and the priority scheduling module is used for controlling each auxiliary load module to start according to a time sequence gradient and coordinating the power conversion module to execute the injection of the compensation charge quantity in stages according to the load loss characteristic parameters corresponding to each auxiliary load module when the auxiliary load modules are started concurrently.
9. The energy efficiency optimizing system of an auxiliary power unit for a battery electric vehicle of claim 1, wherein the compensation control module initiates transient charge injection at a time earlier than the auxiliary load module power on time 10 S to 50 The duration of the transient charge injection is determined by the amount of compensation charge together with the rated peak power of the power conversion module.
10. The energy efficiency optimization system of the auxiliary power unit of the pure electric vehicle according to claim 1, wherein the system is integrated in a whole vehicle controller, and the compensation control module is realized by adopting a processor with a hardware floating point operation unit to support real-time parameter matrix operation required by a parameter inverse algorithm.

Description

Energy efficiency optimization system of auxiliary power unit of pure electric vehicle Technical Field The invention belongs to the technical field of power supply of auxiliary equipment of electric vehicles, and particularly relates to an energy efficiency optimization system of an auxiliary power unit of a pure electric vehicle. Background When a heavy-duty truck or a large bus is in a multi-load concurrent starting working condition, transient extraction current generated by an inductive load often exceeds the real-time regulation bandwidth of the converter, and the physical response time required by overcoming static friction force of a motor rotor and the sampling period of a control loop of the converter have time domain mismatch, so that the bus voltage generates instant drop before a feedback mechanism works, and meanwhile, the capacity of a bus distribution capacitor in a long-term service process is attenuated, so that the stabilizing capability of the system on power impact is weakened. The invention discloses a low-voltage ride-through control method, a static var generator and a storage medium, wherein the low-voltage ride-through control method, the static var generator and the storage medium are compensated by an optimized control algorithm, for example, the Chinese patent publication No. CN109560571B distinguishes a power grid voltage drop mode, a corresponding direct-current bus voltage balance control strategy is selected to inhibit unbalance, the regulation belongs to fault triggering type passive feedback, the regulation is highly dependent on a preset control coefficient, the physical vacuum period between an auxiliary load receiving instruction and an actuating mechanism is difficult to sense, and the mode cannot cope with nonlinear characteristic drift generated by the physical abrasion and the viscosity evolution of a lubricating medium of an auxiliary load, so that the preset control model is mismatched with the physical state of the hardware in the later operation period of the vehicle, and energy closed-loop dispatching between the loads is difficult to realize on the premise of not increasing external perception hardware. Therefore, how to build a predictive potential energy management mechanism by using the physical vacuum period before starting the auxiliary load and realize the on-line inversion and calibration of the physical characteristics of the system on the basis of maintaining the existing hardware architecture becomes the technical problem to be solved by the invention. Disclosure of Invention The invention provides an energy efficiency optimization system of an auxiliary power unit of a pure electric vehicle, which comprises: the power conversion module is connected between the direct current bus and the auxiliary load module; The characteristic sampling module is used for controlling the power conversion module to output a pulse voltage signal to the direct current bus in a pre-conduction sampling period before the auxiliary load module receives the starting signal and the power loop is conducted, and obtaining a current response variable quantity and a bus voltage actual variable rate generated by the response of the direct current bus end to the pulse voltage signal; The compensation control module is used for calculating bus supporting capacity characteristics representing the real-time attenuation state of the direct-current bus end supporting capacitor through a parameter inverse algorithm based on the current response variable quantity and the bus voltage actual variable rate, calculating transient damping characteristics representing the starting resistance offset of the auxiliary load module along with the life cycle evolution, and determining a compensation charge quantity for compensating the starting instant bus voltage drop according to the nonlinear coupling relation between the bus supporting capacity characteristics and the transient damping characteristics; And the power conversion module is used for executing transient electric quantity injection to the direct current bus according to the compensation electric quantity in a preset time window before the auxiliary load module formally executes power extraction so as to offset bus voltage nonlinear dip caused by capacitor aging and load damping offset by utilizing the preset electric quantity of the direct current bus. The system comprises an energy storage module, an energy recovery module, a compensation control module and a power conversion module, wherein the energy storage module is used for monitoring induced electromotive force generated by an internal winding of an auxiliary load module in a shutdown discharging stage and guiding residual magnetic field potential energy generated by the induced electromotive force to a direct current bus to construct a dynamic energy buffer pool, and the compensation control module is also used for reading available charge storage information in the dynamic ene