Charging control system and control method for direct-current charging pile

Abstract

The invention discloses a DC charging pile charging control system and control method, and the system comprises a charging control module which receives charging demand data and charging electric energy data, and generates a charging control signal based on a preset electric energy control function; the charging monitoring module collects charging electric energy data of the first electric energy processing module and the second electric energy processing module; the electric energy adjusting module is used for controlling and adjusting the electric energy transmitted by the first electric energy processing module and the second electric energy processing module; the first electric energy processing module is used for converting electric energy input by the input power supply into stable direct-current electric energy; the second electric energy processing module optimizes the stable direct-current electric energy and then transmits the stable direct-current electric energy to the charging pile; and the electric energy isolation module isolates the electric connection between the charging main loop and the charging secondary loop. The control signal is generated according to the actual working state of the charging pile, the system is controlled and adjusted based on the control signal, the electric energy utilization rate of the charging pile is effectively improved, the electric energy loss is reduced, and the charging efficiency is optimized.

Description

Technical Field

[0001] The present invention relates to the technical field of charging pile charging control, and in particular to a direct current charging pile charging control system and a control method. Background Art

[0002] At present, my country's new energy industry is in a stage of rapid development, and the new energy vehicles derived from it, which use electricity as a driving energy source, have gradually become the most popular type of vehicles. Compared with the traditional energy vehicle industry, mileage anxiety and charging inconvenience are the main bottlenecks restricting the development of the new energy vehicle industry. Nowadays, with the gradual popularization of fast-charging DC charging piles with high power and high charging current on the market, the problem of charging inconvenience has been effectively alleviated, but new problems have followed one after another. In terms of charging efficiency, fast-charging DC charging piles charge faster and more efficiently than slow-charging charging piles, so fast-charging DC charging piles are used more frequently, but fast-charging DC charging piles have a big problem: because they need to match different new energy vehicles, the charging current is large, and the charging power is also large, so the requirements for charging safety and stability are high. The current DC charging piles are not smart enough to control the charging parameters during charging, and cannot be accurately adjusted according to the real-time charging power parameters, resulting in poor control effect and low charging efficiency. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art. The present invention provides a DC charging pile charging control system and a control method, which generates a control signal according to the actual working state of the charging pile, and controls and adjusts the system based on the control signal, effectively improving the power utilization rate of the charging pile, reducing power loss, and optimizing charging efficiency.

[0004] The present invention provides a DC charging pile charging control system, the system comprises a charging control module, a charging monitoring module, a power regulating module, a switch module, a first power processing module, and a second power processing module, the charging control module is respectively connected to the charging monitoring module, the power regulating module, the switch module, the first power processing module, and the second power processing module, the charging detection module and the power regulating module are both connected to the first power processing module and the second power processing module, the input end of the first power processing module is connected to an input power supply, the output end of the first power processing module and the input end of the second power processing module are connected to the switch module, and the output end of the second power processing module is connected to a charging gun;

[0005] The charging control module is used to receive charging demand data from the vehicle and charging power data collected by the charging monitoring module, generate a charging control signal based on a preset power control function, and transmit the charging control signal to the power regulation module;

[0006] The charging monitoring module is used to collect charging power data when the first power processing module and the second power processing module are working, and transmit the collected charging power data to the charging control module;

[0007] The power regulation module is used to control and regulate the power transmitted by the first power processing module and the second power processing module based on the charging control signal;

[0008] The first power processing module is used to convert the power input from the input power source into stable direct current power that can be used for charging;

[0009] The second power processing module is used to optimize the stable DC power and then transmit it to the charging gun;

[0010] The first power processing module, the second power processing module, and the switch module form a main charging circuit, and the main charging circuit is used to process the power input by the input power supply and transmit the processed power to the charging gun;

[0011] The charging control module, the charging monitoring module, and the power regulation module constitute a charging secondary circuit, and the charging secondary circuit is used to collect the charging power data of the charging main circuit, and control and regulate the charging main circuit based on the charging power data;

[0012] An electric energy isolation module is provided between the main charging circuit and the secondary charging circuit, and the electric energy isolation module is used to isolate the electrical connection between the main charging circuit and the secondary charging circuit.

[0013] Furthermore, the charging control module includes a power control unit, a charging control unit, and a billing and metering control unit, and the power control unit, the charging control unit, and the billing and metering control unit all include a microcontroller and a microprocessor.

[0014] Furthermore, the first power processing module includes a circuit breaker, an AC contactor, and a power charging unit;

[0015] The input end of the circuit breaker is connected to the input power supply, the output end of the circuit breaker is connected to the input end of the AC contactor, the output end of the AC contactor is connected to the input end of the electric energy charging unit, and the output end of the electric energy charging unit is connected to the switch module.

[0016] Furthermore, the second power processing module includes a fuse, a shunt, and a DC contactor;

[0017] The input ends of the fuse and the shunt are connected to the switch module, the output ends of the fuse and the shunt are connected to the input end of the DC contactor, and the output end of the DC contactor is connected to the charging gun.

[0018] Furthermore, the charging monitoring module includes a current detector, a voltage detector, and a temperature probe;

[0019] The current detector is used to monitor the charging current data of the first power processing module and the second power processing module, the voltage detector is used to monitor the charging voltage data of the first power processing module and the second power processing module, and the temperature probe is used to monitor the charging temperature data of the first power processing module and the second power processing module.

[0020] Furthermore, the electric energy regulation module includes a charging current regulation module, a charging voltage regulation module and a charging temperature regulation module;

[0021] The charging current regulating module is used to regulate the current of the electric energy transmitted in the first electric energy processing module and the second electric energy processing module;

[0022] The charging voltage regulating module is used to regulate the voltage of the electric energy transmitted in the first electric energy processing module and the second electric energy processing module;

[0023] The charging temperature regulating module is used to regulate the temperature of the first power processing module and the second power processing module.

[0024] Furthermore, the system also includes an energy storage module, which is connected to the output end of the second power processing module and is used to store the DC power output by the second power processing module.

[0025] The present invention also provides a DC charging pile charging control method, which is implemented based on the above-mentioned DC charging pile charging control system, and the method includes:

[0026] The charging control module receives charging demand data from the vehicle to be charged;

[0027] The charging monitoring module collects charging power data of the first power processing module and the second power processing module, and transmits the charging power data to the charging control module;

[0028] The charging control module generates a power control function, processes the charging demand data and the charging power data based on the power control function, generates a charging control signal, and transmits the charging control signal to the power regulation module;

[0029] The power regulating module regulates the power transmitted between the first power processing module and the second power processing module based on the charging control signal;

[0030] The charging monitoring module collects the adjusted charging power data of the first power processing module and the second power processing module, and the charging control module analyzes the adjustment optimization results of the adjusted charging power data.

[0031] Further, the charging control module generates a power control function, processes the charging demand data and the charging power data based on the power control function, generates a charging control signal, and transmits the charging control signal to the power regulation module, including:

[0032] The charging control module generates a current negative sequence control function, processes the charging demand current data in the charging demand data and the charging current data in the charging electric energy data based on the current negative sequence control function, and generates a charging current control signal;

[0033] The charging control module generates a voltage duty cycle compensation function, processes the charging demand voltage data in the charging demand data and the charging voltage data in the charging electric energy data based on the voltage duty cycle compensation function, and generates a charging voltage control signal;

[0034] The charging control module transmits the charging current control signal and the charging voltage control signal to the power regulation module.

[0035] Furthermore, the power regulating module regulates the power transmitted between the first power processing module and the second power processing module based on the charging control signal, including:

[0036] The charging current regulating module and the charging voltage regulating module in the power regulating module respectively adjust the processing parameters of the AC contactor, the power charging unit in the first power processing module, and the DC contactor in the second power processing module based on the charging current control signal and the charging voltage control signal.

[0037] The present invention provides a DC charging pile charging control system and a control method. The real-time charging power data of the DC charging pile charging system is monitored by a charging monitoring module. The charging control module generates a corresponding charging control signal based on a preset power control function. The power regulation module performs control and regulation according to the charging control signal, thereby effectively improving the power utilization rate of the charging pile, reducing power loss, and optimizing charging efficiency. A current negative sequence control function generated by a charging current regulation module and a voltage duty cycle compensation function generated by a charging voltage regulation module are provided to respectively generate a charging current control signal and a charging voltage control signal, thereby effectively improving the accuracy of charging control and improving the optimization quality of charging control. A power isolation module is provided to electrically isolate a charging main circuit for transmitting power from a charging secondary circuit for transmitting control signals, thereby effectively ensuring the safety and stability of the charging control system. An energy storage module is provided to store excess power, thereby improving energy utilization efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0039] Figure 1 This is a diagram of the DC charging pile charging control system architecture in the first embodiment of the present invention;

[0040] Figure 2 is a flow chart of a DC charging pile charging control method in Embodiment 2 of the present invention;

[0041] Figure 3 This is a flow chart of generating a charging control signal in the second embodiment of the present invention. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] In the present invention, it should be understood that terms such as "include" or "have" are intended to indicate the existence of features, numbers, steps, behaviors, components, parts or a combination thereof disclosed in the specification, and are not intended to exclude the possibility that one or more other features, numbers, steps, behaviors, components, parts or a combination thereof exist or are added.

[0044] It should also be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0045] Embodiment 1

[0046] Embodiment 1 of the present invention provides a DC charging pile charging control system, the system comprising a charging control module, a charging monitoring module, a power regulation module, a switch module, a first power processing module, and a second power processing module.

[0047] In an optional implementation of this embodiment, Figure 1 As shown, Figure 1 The architecture diagram of the DC charging pile charging control system in the first embodiment of the present invention is shown, the system includes a charging control module, a charging monitoring module, a power regulation module, a switch module, a first power processing module, and a second power processing module, the charging control module is respectively connected to the charging monitoring module, the power regulation module, the switch module, the first power processing module, and the second power processing module, the charging detection module and the power regulation module are both connected to the first power processing module and the second power processing module, the input end of the first power processing module is connected to the input power supply, the output end of the first power processing module and the input end of the second power processing module are connected to the switch module, and the output end of the second power processing module is connected to the charging gun.

[0048] In an optional implementation of this embodiment, the charging control module is used to receive charging demand data from the vehicle and receive charging power data collected by the charging monitoring module, generate a charging control signal based on a preset power control function, and transmit the charging control signal to the power regulation module.

[0049] Specifically, the charging control module is connected to an input power supply as a working power supply of the charging control module, receives charging demand data from the vehicle to be charged, and receives real-time charging power data of the first power processing module and the second power processing module collected by the charging monitoring module, and processes the charging demand data and the real-time charging power data according to a preset power control function, generates a charging control signal, and finally transmits the generated charging control signal to the power regulation module.

[0050] In an optional implementation of this embodiment, the power control function includes: a current negative sequence control function for controlling current and a voltage duty cycle compensation function for controlling voltage.

[0051] In an optional implementation of this embodiment, the charging control signal includes a charging current control signal, a charging voltage control signal and a charging temperature control signal.

[0052] In an optional implementation of this embodiment, the charging control module includes a charging control unit, a control unit center, and a charging pile terminal control unit, and the charging control unit, the control unit center, and the charging pile terminal control unit all include a microcontroller and a microprocessor.

[0053] Specifically, the charging control module includes a power control unit PCU (Power Control Unit, PCU), a charging control unit CCU (Control Center Unit) and a billing and metering control unit TCU (Thermal Control Unit). The charging control unit, the control unit center and the charging pile terminal control unit cooperate to generate a charging control signal, wherein the charging control unit is used to communicate with other units to complete information exchange and charging process control, the power control unit is used to control the switching elements to realize power distribution, and the billing and metering control unit is used to realize human-computer interaction and cloud communication functions.

[0054] Furthermore, the power control unit, charging control unit and billing and metering control unit are all equipped with a dual processor design of a microcontroller MCU (Microcontroller Unit, MCU) and a microprocessor MPU (Microprocessor Unit, MPU), which can achieve more complex data calculations and more efficient and flexible application design compared to the single MCU or dual MCU solutions commonly used in the industry.

[0055] In an optional implementation of this embodiment, a leakage switch and a switching power supply are provided between the charging control module and the input power supply.

[0056] In an optional implementation of this embodiment, the charging control module transmits the collected charging power data to the cloud based on Ethernet or 4G for storage and backup.

[0057] In an optional implementation of this embodiment, the charging monitoring module is used to collect charging power data when the first power processing module and the second power processing module are working, and transmit the collected charging power data to the charging control module.

[0058] In an optional implementation of this embodiment, the charging monitoring module includes a current detector, a voltage detector, and a temperature probe.

[0059] Specifically, the current detector is used to monitor the charging current data of the first power processing module and the second power processing module, the voltage detector is used to monitor the charging voltage data of the first power processing module and the second power processing module, and the temperature probe is used to monitor the charging temperature data of the first power processing module and the second power processing module.

[0060] Furthermore, the charging monitoring module is connected to the first power processing module, the second power processing module and the power connection line thereof to obtain real-time charging power data of the entire charging pile, and provide data support for the subsequent generation of charging control signals for control and adjustment.

[0061] In an optional implementation of this embodiment, the power regulation module is used to control and regulate the power transmitted by the first power processing module and the second power processing module based on the charging control signal.

[0062] In an optional implementation of this embodiment, the electric energy regulation module includes a charging current regulation module, a charging voltage regulation module and a charging temperature regulation module.

[0063] Specifically, the charging current regulating module is used to regulate the current of the electric energy transmitted between the first electric energy processing module and the second electric energy processing module; the charging voltage regulating module is used to regulate the voltage of the electric energy transmitted between the first electric energy processing module and the second electric energy processing module; and the charging temperature regulating module is used to regulate the temperature of the first electric energy processing module and the second electric energy processing module.

[0064] Furthermore, the charging current regulating module regulates the current of the electric energy transmitted in the first electric energy processing module and the second electric energy processing module based on the charging current control signal generated and transmitted by the charging control module; the charging voltage regulating module regulates the voltage of the electric energy transmitted in the first electric energy processing module and the second electric energy processing module based on the charging voltage control signal generated and transmitted by the charging control module; and the charging temperature regulating module regulates the temperature of the first electric energy processing module and the second electric energy processing module based on the charging temperature control signal generated and transmitted by the charging control module.

[0065] In an optional implementation of this embodiment, the power regulation module is constructed based on a device framework of a front-stage rectifier and a rear-stage resonant converter.

[0066] In an optional implementation of this embodiment, the first power processing module is used to convert the power input by the input power supply into stable direct current power that can be used for charging.

[0067] Specifically, the input power source is a three-phase AC power source or a DC power source.

[0068] In an optional implementation of this embodiment, the first power processing module includes a circuit breaker, an AC contactor, and an electric energy charging unit; the input end of the circuit breaker is connected to the input power supply, the output end of the circuit breaker is connected to the input end of the AC contactor, the output end of the AC contactor is connected to the input end of the electric energy charging unit, and the output end of the electric energy charging unit is connected to the switch module.

[0069] Specifically, the circuit breaker and the AC contactor mainly play the role of emergency switches, and when encountering an emergency situation (such as excessive current or excessive voltage), the circuit is urgently cut off.

[0070] Furthermore, a lightning arrester is provided between the circuit breaker and the input power supply.

[0071] In an optional implementation of the present embodiment, the power charging unit is provided with sub-units such as transformer, rectifier, and filter, and the power charging unit is used to convert the input power processed by the first power processing module into stable direct current that can be accepted by the battery.

[0072] In an optional implementation of this embodiment, the second power processing module is used to optimize the stable DC power and then transmit it to the charging gun.

[0073] In an optional implementation of this embodiment, the second power processing module includes a fuse, a shunt, and a DC contactor; the input ends of the fuse and the shunt are connected to the switch module, the output ends of the fuse and the shunt are connected to the input end of the DC contactor, and the output end of the DC contactor is connected to the charging pile.

[0074] Specifically, the input electric energy passing through the switch module passes through the fuse and the shunt, wherein the current detector of the charging monitoring module collects charging current data in the shunt, and the voltage detector collects charging voltage data in the fuse.

[0075] More importantly, the DC contactor mainly plays the role of a switch. After completing the charging power processing operations of the first power processing module and the second power processing module, as well as the insulation detection operation, the DC contactor closes to complete the final operation of transmitting power to the charging gun.

[0076] In an optional implementation of this embodiment, the switch module is a combination of a copper bus and a power distribution unit PDU (Power Distribution Unit, PDU), and the switch module can reasonably distribute the electric energy output by the first power processing module and transmit it to the second power processing module.

[0077] In an optional implementation of this embodiment, the first power processing module, the second power processing module, and the switch module constitute a main charging circuit, and the main charging circuit is used to process the power input by the input power supply and transmit the processed power to the charging gun;

[0078] The charging control module, the charging monitoring module, and the power regulation module constitute a charging secondary circuit, and the charging secondary circuit is used to collect the charging power data of the charging main circuit, and control and regulate the charging main circuit based on the charging power data.

[0079] Specifically, the charging main circuit is mainly used for transmitting electric energy, and the charging secondary circuit is mainly used for transmitting control signals. An electric energy isolation module is provided between the charging main circuit and the charging secondary circuit, and the electric energy isolation module is used to isolate the electrical connection between the charging main circuit and the charging secondary circuit.

[0080] It should be noted that most of the current charging systems do not achieve electrical isolation between power transmission and control signal transmission. Therefore, the transmission of power back to the control signal causes greater interference and cannot achieve the most ideal control accuracy. At the same time, the transmission of control signals will affect the efficiency of power transmission, resulting in increased losses. In this embodiment, a power isolation module is provided between the charging main circuit for power transmission and the charging secondary circuit for control signal transmission, which can effectively isolate the electrical interference between power transmission and control signal transmission, thereby improving the efficiency and accuracy of charging and reducing power loss.

[0081] In an optional implementation of this embodiment, the system also includes a heat dissipation module, which is included in the charging temperature adjustment module in the charging secondary circuit. The heat dissipation module is provided with a high-power heat dissipation fan. The heat dissipation module performs heat dissipation processing by generating a charging temperature control signal after the charging temperature data collected by the charging control module.

[0082] In an optional implementation of this embodiment, the system also includes a card reader and a display screen. The card reader is used to read the charging card information and provide real-time metering and billing functions of the charging pile such as scanning codes, swiping cards, and charging mode settings. The display screen is used to display real-time control information of the charging system.

[0083] In summary, the first embodiment of the present invention provides a DC charging pile charging control system, which monitors the real-time charging power data of the DC charging pile charging system through a charging monitoring module, and the charging control module generates a corresponding charging control signal based on a preset power control function. The power regulation module performs control and regulation according to the charging control signal, effectively improving the power utilization rate of the charging pile, reducing power loss, and optimizing the charging efficiency; the current negative sequence control function generated by the charging current regulation module and the voltage duty cycle compensation function generated by the charging voltage regulation module are set to generate a charging current control signal and a charging voltage control signal respectively, effectively improving the accuracy of charging control and improving the optimization quality of charging control; an energy isolation module is set to electrically isolate the charging main circuit for transmitting electric energy and the charging secondary circuit for transmitting control signals, effectively ensuring the safety and stability of the charging control system; an energy storage module is set to store excess electric energy to improve energy utilization efficiency.

[0084] Embodiment 2

[0085] Embodiment 2 of the present invention provides a DC charging pile charging control method, which is implemented based on the DC charging pile charging control system described in Embodiment 1, and the method includes: the charging control module receives charging demand data from a vehicle to be charged; the charging monitoring module collects charging power data of the first power processing module and the second power processing module, and transmits the charging power data to the charging control module; the charging control module generates a power control function, processes the charging demand data and the charging power data based on the power control function, generates a charging control signal, and transmits the charging control signal to the power regulation module; the power regulation module regulates the power transmitted in the first power processing module and the second power processing module based on the charging control signal; the charging monitoring module collects the adjusted charging power data of the first power processing module and the second power processing module, and the charging control module performs regulation optimization result analysis on the adjusted charging power data.

[0086] In an optional implementation of this embodiment, Figure 2 As shown, Figure 2 The flow chart of the DC charging pile charging control method in the second embodiment of the present invention is shown, which includes the following steps:

[0087] S201, the charging control module receives charging demand data from a vehicle to be charged;

[0088] In an optional implementation of this embodiment, the charging control module receives charging demand voltage data and charging demand current data sent from the BMS of the vehicle to be charged.

[0089] S202, the charging monitoring module collects charging power data of the first power processing module and the second power processing module, and transmits the charging power data to the charging control module;

[0090] In an optional implementation of the present embodiment, the current detector in the charging monitoring module collects the charging current data of the first power processing module and the second power processing module, the voltage detector in the charging monitoring module collects the charging voltage data of the first power processing module and the second power processing module, and the temperature probe in the charging monitoring module collects the charging temperature data of the first power processing module and the second power processing module.

[0091] Specifically, the current detector is connected to the shunt in the second power processing module to collect charging current data, the voltage detector is connected to the fuse in the second power processing module to collect charging voltage data, and the temperature probe collects charging temperature data.

[0092] In an optional implementation of this embodiment, the charging monitoring module transmits the collected charging power data to the charging control module based on an RS485 communication bus.

[0093] S203, the charging control module generates a power control function, processes the charging demand data and the charging power data based on the power control function, generates a charging control signal, and transmits the charging control signal to the power regulation module;

[0094] In an optional implementation of this embodiment, the charging control module compares the charging current demand data in the charging demand data with the charging current data in the charging power data, and compares the charging voltage demand data in the charging demand data with the charging current data in the charging voltage data.

[0095] Further, when there is a difference between the charging current demand data and the charging current data, or when there is a difference between the charging voltage demand data and the charging voltage data, then

[0096] In an optional implementation of this embodiment, Figure 3 As shown, Figure 3 The flowchart of generating a charging control signal in the second embodiment of the present invention is shown, comprising the following steps:

[0097] S301, generating a charging current control signal;

[0098] In an optional implementation of this embodiment, the charging control module generates a current negative sequence control function, processes the charging current data in the charging electric energy data based on the current negative sequence control function, and generates a charging current control signal.

[0099] Specifically, since there is a certain deviation between the voltage reference value and the actual voltage value of the electric energy output by the electric energy charging unit, its current usually has a positive-sequence component reference value and a negative-sequence component reference value, respectively. The negative-sequence current in the negative-sequence component will have a certain interference with the intensity and stability of the output electric energy. Therefore, it is necessary to set an electric energy negative-sequence control function here to strip off the negative-sequence current component in the output electric energy, improve the efficiency of electric energy output, and reduce electric energy loss.

[0100] Specifically, the current reference value of the electric energy output by the electric energy charging unit is expressed as:

[0101]

[0102] In the formula, I o ′ is the current reference value, K p is the high frequency gain parameter, K i is the low frequency gain parameter, U′ R is the voltage reference value, U R is the actual value of voltage.

[0103] Furthermore, in order to suppress the negative sequence component of the current, the reference values ​​of the negative sequence components of the current in the active state and the reactive state need to be set to 0 in the dq coordinate system, and the negative sequence components of the current in the active state and the reactive state are obtained as follows:

[0104]

[0105] p′ 0 =U R I o '

[0106] q′ 0 =0

[0107] In the formula, i′ d is the negative sequence component of current in active state, i′ q is the negative sequence component of current in reactive state, p′ 0 is the active power reference value, q′ 0 is the reactive power reference value, U R is the actual value of voltage, I o ′ is the current reference value.

[0108] In an optional implementation of this embodiment, a current loop sliding mode objective function is set, and a stable condition function of a sliding mode parameter is obtained by substituting the current negative sequence component into the stable condition function of the sliding mode parameter, and a charging current control signal is generated based on the stable condition function of the sliding mode parameter.

[0109] Specifically, here, according to the basic conditions of three-phase balance and the three-phase synchronous rotating coordinate system benchmark, a preliminary standard expression is obtained, including:

[0110]

[0111] In the formula, u q is the control parameter on the q axis, u d is the control parameter on the d-axis, K p is the proportionality coefficient, K i is the integration coefficient, K d is the differential coefficient, s is the empirical constant, i q is the initial component of the current on the q axis, i′ q is the final component of the current in the q axis, i d is the initial component of the current on the d axis, i′ d is the final component of the current on the d-axis, e q is the voltage vector on the q axis, e d is the voltage vector on the d-axis.

[0112] Furthermore, the closed-loop line length, as well as the equivalent gain values ​​of current sampling, voltage sampling and power delay are set to obtain the closed-loop dynamic function of the power grid. According to the optimal operating time and overshoot parameters of the charging pile, the damping adjustment proportional coefficient that meets the optimal response coefficient, the most stable voltage, current and power three-phase changes is derived. The expression includes:

[0113]

[0114] In the formula, K p is the proportionality coefficient, K p is the proportionality coefficient, K i is the integration coefficient, K d is the differential coefficient, L is the closed-loop line length, ξ is the damping coefficient ratio, N is the optimal response coefficient, T k is the current sampling equivalent gain value, T S is the voltage sampling equivalent gain value, and R is the equivalent resistance.

[0115] S302, generating a charging voltage control signal;

[0116] In an optional implementation of this embodiment, the charging control module generates a voltage duty cycle compensation function, processes the charging voltage data in the charging power data based on the voltage duty cycle compensation function, and generates a charging voltage control signal.

[0117] Specifically, in the transformer unit in the electric energy charging unit, there is bidirectional transmission of energy, which is used to balance the power demand caused by the distributed power supply and load changes. Therefore, the optimized control thereof can improve the efficiency and stability of the charging conversion. Since the multi-phase interleaved parallel bidirectional conversion method often causes phase uneven current due to the difference in parasitic parameters during the conversion process, it is specifically manifested as the instability of the voltage duty cycle value. Therefore, it is necessary to set a voltage duty cycle compensation function to compensate for it, so as to improve the efficiency and stability of the charging conversion.

[0118] In an optional implementation of this embodiment, the average inductor current corresponding to the corresponding voltage duty cycle in multiple control cycles is obtained by analysis, and the expression includes:

[0119]

[0120] In the formula, I l (k) is the average inductor current sampled during the kth control cycle, I l (k+1) is the average inductor current sampled in the k+1th control cycle, U i (k) is the input voltage value sampled in the kth control cycle, U i (k+1) is the input voltage value sampled in the k+1th control cycle, U o (k) is the output voltage value sampled in the kth control cycle, D(k) is the voltage duty cycle of the kth control cycle, T is the period, L 1 is the inductance value, C 1 is the capacitance value, and R is the resistance value.

[0121] Furthermore, the current loop sliding mode objective function in step S301 is extracted, a prediction model is established, the average inductor current value is input, and the optimal voltage duty cycle of the current control cycle is output. When the average inductor current of each phase is equal and the current deviation of each phase is zero under the optimal voltage duty cycle, the voltage duty cycle of each phase output by the prediction control reaches the optimal value, and the voltage duty cycle compensation is realized, and the charging voltage control signal is generated in summary.

[0122] S303, generating a charging temperature control signal;

[0123] In an optional implementation of this embodiment, the charging control module generates a temperature adjustment function, processes the charging temperature requirement data in the charging requirement function and the charging temperature data in the charging power data based on the temperature adjustment function, and generates a charging temperature control signal.

[0124] Specifically, the difference between the charging temperature requirement data and the charging temperature data is calculated, the difference is processed based on the temperature adjustment function, and the charging temperature control signal is generated.

[0125] S304: Transmit the charging current control signal, the charging voltage control signal and the charging temperature control signal to the power regulation module.

[0126] In an optional implementation of this embodiment, the charging control module transmits the charging current control signal, the charging voltage control signal and the charging temperature control signal to the power regulation module.

[0127] Specifically, the charging control module transmits the charging current control signal to the charging current regulating module of the power regulating module, transmits the charging voltage control signal to the charging voltage regulating module of the power regulating module, and transmits the charging temperature control signal to the charging temperature regulating module of the power regulating module.

[0128] S204, the power regulation module regulates the power transmitted between the first power processing module and the second power processing module based on the charging control signal;

[0129] In an optional implementation of this embodiment, the charging current regulation module, the charging voltage regulation module and the charging temperature regulation module in the power regulation module respectively adjust the processing parameters of the AC contactor, the power charging unit in the first power processing module, and the DC contactor in the second power processing module based on the charging current control signal, the charging voltage control signal and the charging temperature control signal.

[0130] Specifically, the charging temperature adjustment module is mainly adjusted through the heat dissipation module.

[0131] S205, the charging monitoring module collects the adjusted charging power data of the first power processing module and the second power processing module, and the charging control module analyzes the adjustment optimization results of the adjusted charging power data.

[0132] In an optional implementation of this embodiment, after the adjustment is completed, the charging monitoring module collects the charging power data of the first power processing module and the second power processing module after adjustment, including charging current data, charging voltage data, and charging temperature data, and compares them with the charging power data before adjustment to obtain an adjustment optimization result analysis report.

[0133] Specifically, it is determined according to the adjustment optimization result analysis report whether the charging power data of the first power processing module and the second power processing module have been optimized and adjusted according to the charging demand data of the vehicle to be charged.

[0134] In summary, the second embodiment of the present invention provides a DC charging pile charging control method, which is implemented based on the DC charging pile charging control system described in the first embodiment. The real-time charging power data of the DC charging pile charging system is monitored by the charging monitoring module. The charging control module generates a corresponding charging control signal based on a preset power control function. The power regulation module performs control and regulation according to the charging control signal, effectively improving the power utilization rate of the charging pile, reducing power loss, and optimizing the charging efficiency; the current negative sequence control function generated by the charging current regulation module and the voltage duty cycle compensation function generated by the charging voltage regulation module are set to generate the charging current control signal and the charging voltage control signal respectively, effectively improving the accuracy of the charging control and improving the optimization quality of the charging control; an energy isolation module is set to electrically isolate the charging main circuit for transmitting electric energy and the charging secondary circuit for transmitting the control signal, effectively ensuring the safety and stability of the charging control system; an energy storage module is set to store excess electric energy to improve energy utilization efficiency.

[0135] The above is a detailed introduction to a DC charging pile charging control system and control method provided by the present invention. A person skilled in the art can understand that all or part of the steps in the various methods of the above embodiments can be completed by instructing the relevant hardware through a program, and the program can be stored in a computer-readable storage medium. The storage medium may include: a read-only memory (ROM), a random access memory (RAM), a disk or an optical disk, etc.

[0136] In addition, the embodiments of the present invention are described in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A DC charging pile charging control system, characterized in that: The system includes a charging control module, a charging monitoring module, a power regulation module, a switch module, a first power processing module, and a second power processing module. The charging control module is respectively connected to the charging monitoring module, the power regulation module, the switch module, the first power processing module, and the second power processing module. The charging detection module and the power regulation module are both connected to the first power processing module and the second power processing module. The input end of the first power processing module is connected to an input power supply, the output end of the first power processing module and the input end of the second power processing module are connected to the switch module, and the output end of the second power processing module is connected to a charging gun. The charging control module is used to receive charging demand data from the vehicle and charging power data collected by the charging monitoring module, generate a charging control signal based on a preset power control function, and transmit the charging control signal to the power regulation module; The charging monitoring module is used to collect charging power data when the first power processing module and the second power processing module are working, and transmit the collected charging power data to the charging control module; The power regulation module is used to control and regulate the power transmitted by the first power processing module and the second power processing module based on the charging control signal; The first power processing module is used to convert the power input from the input power source into stable direct current power that can be used for charging; The second power processing module is used to optimize the stable DC power and then transmit it to the charging gun; The first power processing module, the second power processing module, and the switch module form a main charging circuit, and the main charging circuit is used to process the power input by the input power supply and transmit the processed power to the charging gun; The charging control module, the charging monitoring module, and the power regulation module constitute a charging secondary circuit, and the charging secondary circuit is used to collect the charging power data of the charging main circuit, and control and regulate the charging main circuit based on the charging power data; An electric energy isolation module is provided between the main charging circuit and the secondary charging circuit, and the electric energy isolation module is used to isolate the electrical connection between the main charging circuit and the secondary charging circuit.

2. The DC charging pile charging control system according to claim 1, characterized in that: The charging control module includes a power control unit, a charging control unit, and a charging and metering control unit. The power control unit, the charging control unit, and the charging and metering control unit all include a microcontroller and a microprocessor.

3. The DC charging pile charging control system according to claim 1, characterized in that: The first power processing module includes a circuit breaker, an AC contactor, and a power charging unit; The input end of the circuit breaker is connected to the input power supply, the output end of the circuit breaker is connected to the input end of the AC contactor, the output end of the AC contactor is connected to the input end of the electric energy charging unit, and the output end of the electric energy charging unit is connected to the switch module.

4. The DC charging pile charging control system according to claim 1, characterized in that: The second power processing module includes a fuse, a shunt, and a DC contactor; The input ends of the fuse and the shunt are connected to the switch module, the output ends of the fuse and the shunt are connected to the input end of the DC contactor, and the output end of the DC contactor is connected to the charging gun.

5. The DC charging pile charging control system according to claim 1, characterized in that: The charging monitoring module includes a current detector, a voltage detector, and a temperature probe; The current detector is used to monitor the charging current data of the first power processing module and the second power processing module, the voltage detector is used to monitor the charging voltage data of the first power processing module and the second power processing module, and the temperature probe is used to monitor the charging temperature data of the first power processing module and the second power processing module.

6. The DC charging pile charging control system according to claim 1, characterized in that: The electric energy regulation module includes a charging current regulation module, a charging voltage regulation module and a charging temperature regulation module; The charging current regulating module is used to regulate the current of the electric energy transmitted in the first electric energy processing module and the second electric energy processing module; The charging voltage regulating module is used to regulate the voltage of the electric energy transmitted in the first electric energy processing module and the second electric energy processing module; The charging temperature regulating module is used to regulate the temperature of the first power processing module and the second power processing module.

7. The DC charging pile charging control system according to claim 1, characterized in that: The system further includes an energy storage module, which is connected to the output end of the second power processing module and is used to store the DC power output by the second power processing module.

8. A DC charging pile charging control method, characterized in that: The DC charging pile charging control method is implemented based on the DC charging pile charging control system according to any one of claims 1 to 7, and the method comprises: The charging control module receives charging demand data from the vehicle to be charged; The charging monitoring module collects charging power data of the first power processing module and the second power processing module, and transmits the charging power data to the charging control module; The charging control module generates a power control function, processes the charging demand data and the charging power data based on the power control function, generates a charging control signal, and transmits the charging control signal to the power regulation module; The power regulating module regulates the power transmitted between the first power processing module and the second power processing module based on the charging control signal; The charging monitoring module collects the adjusted charging power data of the first power processing module and the second power processing module, and the charging control module analyzes the adjustment optimization results of the adjusted charging power data.

9. The DC charging pile charging control method according to claim 8, characterized in that: The charging control module generates a power control function, processes the charging demand data and the charging power data based on the power control function, generates a charging control signal, and transmits the charging control signal to the power regulation module, including: The charging control module generates a current negative sequence control function, processes the charging demand current data in the charging demand data and the charging current data in the charging electric energy data based on the current negative sequence control function, and generates a charging current control signal; The charging control module generates a voltage duty cycle compensation function, processes the charging demand voltage data in the charging demand data and the charging voltage data in the charging electric energy data based on the voltage duty cycle compensation function, and generates a charging voltage control signal; The charging control module generates a temperature adjustment function, processes the charging requirement temperature data in the charging requirement data and the charging temperature data in the charging electric energy data based on the temperature adjustment function, and generates a charging temperature control signal; The charging control module transmits the charging current control signal, the charging voltage control signal and the charging temperature control signal to the power regulation module.

10. The DC charging pile charging control method according to claim 9, characterized in that: The power regulating module regulating the power transmitted between the first power processing module and the second power processing module based on the charging control signal includes: The charging current regulating module and the charging voltage regulating module in the power regulating module respectively adjust the processing parameters of the AC contactor, the power charging unit in the first power processing module, and the DC contactor in the second power processing module based on the charging current control signal and the charging voltage control signal.

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