Generator car tail end drainage device for monitoring and correcting current distortion and working method of generator car tail end drainage device

Abstract

The invention discloses a generator car tail end drainage device for monitoring and correcting current distortion and a working method of the generator car tail end drainage device, and relates to the technical field of generator car tail end drainage. The device comprises a current sensor, a voltage sensor, a distortion monitoring unit, a current correction unit, a driving unit and an electric contact unit. An electrical load lead is connected with a measuring terminal of the voltage sensor and penetrates through a measuring hole of the current sensor to be connected with the electrical contact unit, and a signal output terminal of the voltage sensor and a signal output terminal of the current sensor are connected with the distortion monitoring unit. And the distortion monitoring unit, the current correction unit, the driving unit and the electric contact unit are connected in sequence. According to the invention, the correction current stripping the unbalanced component, the reactive component and the harmonic component can be output, so that the power supply side current distortion of the generator car is inhibited, the power quality of power supply of the mobile generator car is improved, and the power utilization safety is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of terminal current drainage of a power generation vehicle, and in particular to a terminal current drainage device of a power generation vehicle for monitoring and correcting current distortion and a working method thereof. Background Art

[0002] Mobile power generators serve as emergency power sources, enabling rapid access to the grid during utility outages or faults. They provide temporary power support to critical users and areas, effectively shortening outages and ensuring users' normal production and daily electricity needs. During ongoing grid maintenance, mobile power generators ensure that users in the maintenance area are not affected by the outage, thereby minimizing the economic and social impacts of such outages. However, when connected to the distribution network, the electricity generated by mobile power generators often suffers from power quality issues such as high output current harmonics and severe waveform distortion.

[0003] The current distortion of the power supply from the generator vehicle has multiple hazards: (1) it causes harmonics in the distribution network, reducing the quality of power. Excessive amplitude of high-order harmonics can cause malfunctions of relays, control devices and computers; (2) it affects the image quality of equipment such as X-ray instruments, oscilloscopes and televisions, reducing their effectiveness; (3) it causes measurement errors in metering instruments, resulting in unreasonable electricity charges; (4) the harmonics generated by current distortion can interfere with the communication system, making electromagnetic compatibility issues more prominent and affecting communication quality; (5) current distortion can increase the harmonic current of the power grid, thereby increasing the loss of the power grid and reducing transmission efficiency. The current distortion problem has significant hazards in the power system and seriously threatens the safety of electricity use. Summary of the Invention

[0004] The purpose of the present invention is to provide a terminal current diversion device for a power generation vehicle for monitoring and correcting current distortion and a working method thereof, which can improve the safety of electricity use.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] A power generation vehicle terminal current diversion device for current distortion monitoring and correction includes: a current sensor, a voltage sensor, a distortion monitoring unit, a current correction unit, a drive unit, and an electrical contact unit; an electric load lead is connected to the measuring terminal of the voltage sensor and passed through the measuring hole of the current sensor to connect to the electrical contact unit; a signal output terminal of the voltage sensor and a signal output terminal of the current sensor are connected to the distortion monitoring unit; and the distortion monitoring unit, the current correction unit, the drive unit, and the electrical contact unit are connected in sequence;

[0007] The distortion monitoring unit is used to calculate the voltage signal and current signal measured by the sensor to obtain component data in the current signal, and perform correction calculation based on each component data to obtain a correction current reference value; each component data includes an unbalanced component, a reactive component and a harmonic component;

[0008] The current correction unit is used to predict according to the correction current reference value and a discrete mathematical prediction model to obtain a switch action timing parameter; the discrete mathematical prediction model is constructed based on the topological structure of the electrical contact unit in a set coordinate system;

[0009] The driving unit is used to perform signal conditioning according to the switching action timing parameters to obtain a driving signal and a bias voltage corresponding to the switching action;

[0010] The electrical contact unit is used to control the on and off of the switch element according to the driving signal and the bias voltage.

[0011] Optionally, the current sensor uses three through-hole current sensors, which are used to measure the three-phase currents A, B, and C respectively.

[0012] Optionally, the voltage sensor uses three Hall voltage sensor units, which are used to measure the three-phase voltages A, B, and C respectively.

[0013] Optionally, the electrical contact unit is composed of 11 electrical contact switches, including 3 main switches and 8 auxiliary switches; wherein, each main switch is connected to the main circuit of the three-phase circuit, and each auxiliary switch is grouped in pairs to form 4 bridge arms, each bridge arm has two switch electrical contacts, and the lead-out wires of each switch electrical contact are respectively connected to the three-phase line and the neutral line of the main circuit.

[0014] Optionally, the main switch adopts a high-power MOSFET, and the auxiliary switch adopts a fast IGBT switch.

[0015] The present invention discloses a working method of a terminal current diversion device for a power generation vehicle for monitoring and correcting current distortion, which is applied to the device described above and comprises:

[0016] Acquiring voltage and current signals on the electrical load leads;

[0017] Calculating the voltage signal and the current signal to obtain component data of the current signal, and performing correction calculation based on the component data to obtain a corrected current reference value; wherein the component data includes an unbalanced component, a reactive component, and a harmonic component;

[0018] Predicting according to the correction current reference value and a discrete mathematical prediction model to obtain a switch action timing parameter; the discrete mathematical prediction model is constructed based on the topological structure of the electrical contact unit in a set coordinate system;

[0019] Performing signal conditioning according to the switching action timing parameters to obtain a drive signal and a bias voltage corresponding to the switching action;

[0020] The on and off of the switching element is controlled according to the driving signal and the bias voltage.

[0021] Optionally, the calculation process of the correction current reference value is:

[0022] Set current signal i al 、i bl and i cl Based on the symmetrical component method, the three-phase measured current is directly accumulated and multiplied by the coefficient 1 / 3 to obtain the zero-sequence component i0 in the power supply current. The zero-sequence component is subtracted from each phase current to obtain the three-phase current i′ after the zero-sequence component is separated. al , i′ bl and i′ cl After separating the zero-sequence component, according to the principle of symmetrical component method, the three-phase current i′ represented in the abc coordinate system is al (t), i′ bl (t) and i′ cl (t) is converted into the load current i in the α-β coordinate system α (t) and i β (t), load current i α (t) and i β (t) is expressed as the sum of the positive sequence and negative sequence currents, and the load current i is separated by T / 4 delay signal separation method. α (t) and i β (t) represents the current signal delay T / 4, then i α (tT / 4) and i β The positive sequence component i of the current in the expression (tT / 4) α1 (t), i β1 (t) and negative sequence component i α2 (t), i β2 (t) being separated;

[0023] Based on the positive sequence component and negative sequence component of any phase, combined with the real-time phase of the corresponding phase positive sequence voltage e, the instantaneous active power i of the three-phase circuit is calculated. p and instantaneous reactive power i q ; Then we can get the instantaneous active power p and instantaneous reactive power q of the circuit in the α-β coordinate system; the instantaneous active power and instantaneous reactive power are expressed as the fundamental current i in the α-β coordinate systemaj (t) and i βj (t) function, and then calculate the fundamental wave i through p and q αj (t) and i βj (t); finally, i αj (t) and i βj (t) Perform coordinate transformation from the α-β coordinate system to the abc coordinate system to obtain the three-phase fundamental current i in the abc coordinate system aj 、i bj and i cj , the fundamental current and the measured current i al 、i bl and i cl Subtract and get the current unbalance component i az 、i bz and i cz ; Add the separated current unbalanced component, reactive component and harmonic component to obtain the corrected current value i ar 、i br and i cr .

[0024] Optionally, the calculation process of the switching action timing parameters is:

[0025] Firstly, a discrete mathematical model of the electrical contact unit in the α-β-0 coordinate is constructed based on the topological structure of the electrical contact unit. The current value in the specific switch state x at the n+1th moment is expressed as the output equivalent voltage U of the electrical contact unit in the specific switch state x at the n+1th moment. ax 、U βx 、U 0x , three-phase equivalent voltage e on the grid side αs 、e βs 、e 0s , and the corrected current value i at the nth moment αr 、i βr and i 0r function, and construct a discrete mathematical prediction model and a switch state table; the switch state table includes an equivalent output voltage table of all on-off state combinations of the three main switches and eight auxiliary switches of the electrical contact unit;

[0026] Substitute the voltage and current at the n+1 sampling moment in the α-β-0 coordinate system and the switch state table into the discrete mathematical prediction model to predict the output current prediction value at the n+2 sampling moment and all switch states; use the absolute value of the difference between the correction current reference value and the predicted value output by the distortion monitoring unit at the n+2 moment to construct the cost function f gx ; Select the switch state that makes the cost function take the minimum value, determine the switch state quantity corresponding to the output current closest to the reference current, and obtain the switch action timing parameters.

[0027] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0028] The present invention discloses a terminal diversion device for a power generation vehicle for current distortion monitoring and correction and a working method thereof. The device comprises a current sensor, a voltage sensor, a distortion monitoring unit, a current correction unit, a drive unit and an electrical contact unit. An electric load lead is connected to the measuring terminal of the voltage sensor and is connected to the electrical contact unit through the measuring hole of the current sensor. The signal output terminal of the voltage sensor and the signal output terminal of the current sensor are connected to the distortion monitoring unit. The distortion monitoring unit, the current correction unit, the drive unit and the electrical contact unit are connected in sequence.

[0029] Among them, the distortion monitoring unit is used to calculate the voltage waveform and current waveform measured by the sensor to obtain each component data in the current signal, and perform correction calculation based on each component data to obtain a corrected current reference value; each component data includes an unbalanced component, a reactive component and a harmonic component; the current correction unit is used to perform prediction based on the corrected current reference value and a discrete mathematical prediction model to obtain a switching action timing parameter; the discrete mathematical prediction model is constructed based on the topological structure of the electrical contact unit in a set coordinate system; the driving unit is used to perform signal conditioning according to the switching action timing parameters to obtain a driving signal and a bias voltage corresponding to the switching action; the electrical contact unit is used to control the on and off of the switching element according to the driving signal and the bias voltage.

[0030] Therefore, the present invention can output a correction current that strips off unbalanced components, reactive components, and harmonic components, thereby suppressing current distortion on the power supply side of the power generation vehicle, improving the power quality of the mobile power generation vehicle, and further improving power safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. 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 any creative work.

[0032] Figure 1 This is a schematic structural diagram of the terminal current diversion device for the power generation vehicle for current distortion monitoring and correction according to the present invention;

[0033] Figure 2 Schematic diagram of the structure of the electrical contact unit in this embodiment;

[0034] Figure 3Schematic diagram of the working logic of the current correction unit in this embodiment;

[0035] Figure 4 Schematic diagram of the flow chart of the working method of the terminal current diversion device of the power generation vehicle for current distortion monitoring and correction in this embodiment. DETAILED DESCRIPTION

[0036] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 making creative efforts are within the scope of protection of the present invention.

[0037] The purpose of the present invention is to provide a terminal current diversion device for a power generation vehicle for monitoring and correcting current distortion and a working method thereof, which can improve the safety of electricity use.

[0038] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0039] like Figure 1 As shown, the present invention provides a power generation vehicle end diversion device for current distortion monitoring and correction, comprising: a current sensor, a voltage sensor, a distortion monitoring unit, a current correction unit, a drive unit and an electrical contact unit; an electric load lead is connected to the measuring terminal of the voltage sensor, and is connected to the electrical contact unit through the measuring hole of the current sensor, the signal output terminal of the voltage sensor and the signal output terminal of the current sensor are connected to the distortion monitoring unit, and the distortion monitoring unit, the current correction unit, the drive unit and the electrical contact unit are connected in sequence.

[0040] Among them, the distortion monitoring unit is used to calculate the voltage signal and current signal measured by the sensor to obtain each component data in the current signal, and perform correction calculation based on each component data to obtain a corrected current reference value; each component data includes an unbalanced component, a reactive component and a harmonic component; the current correction unit is used to perform prediction based on the corrected current reference value and a discrete mathematical prediction model to obtain a switching action timing parameter; the discrete mathematical prediction model is constructed based on the topological structure of the electrical contact unit in a set coordinate system; the driving unit is used to perform signal conditioning according to the switching action timing parameters to obtain a driving signal and a bias voltage corresponding to the switching action; the electrical contact unit is used to control the on and off of the switching element according to the driving signal and the bias voltage.

[0041] As a specific embodiment, the power generation vehicle is connected to the electrical contact unit of the terminal drainage device via a wire, and the output end of the electrical contact unit is connected to the power load via a wire. Therefore, the output lead of the drainage device is the same as the lead of the power load. The output lead of the drainage device is connected to the voltage sensor measurement terminal and passes through the measurement hole of the current sensor. The voltage sensor signal output terminal and the current sensor signal output terminal are connected to the current detection unit, which monitors the output voltage and current waveforms of the power supply side in real time and sends them to the distortion monitoring unit. The distortion monitoring unit analyzes and calculates the measured voltage and current signals, determines the unbalanced component, reactive component, and harmonic component in the current signal, and separates them to obtain a corrected current reference value, which is output from the output port of the current monitoring unit. The input port of the current correction unit is connected to the output port of the distortion monitoring unit through a lead, receives the correction current reference value output by the distortion monitoring unit, performs model predictive control analysis based on the current reference value, calculates the switching action timing parameters of the electrical contact unit, modulates the switching action timing parameters to generate a square wave control signal with adjustable duty cycle, and outputs it from the output port of the current correction unit; the driving unit is connected to the output port of the current correction unit through a wire, receives the switch trigger action signal output by the current correction unit, and outputs the driving signal and bias voltage required for the electrical contact switch action after signal conditioning; the electrical contact unit is composed of 11 electrical contact switches, such as Figure 2 As shown, the system includes three main switches and eight auxiliary switches. The main switches are connected to the three-phase main circuit and serve as the primary switching devices connecting the three-phase power supply of the generator car to the load. The eight auxiliary switches are grouped in pairs to form four bridge arms. Wires extend from the connection point between the two switches on each bridge arm and are connected to the three-phase main circuit and the neutral line. The 11 switches in the electrical contactor unit receive switching signals from the drive unit. By controlling the on and off of the switching elements in the electrical contactor unit, the difference between the output current on the generator car's power supply side and the correction current is maintained below a certain threshold, thereby achieving the purpose of current distortion correction.

[0042] A method for operating the terminal current diversion device of a power generation vehicle based on the above-mentioned current distortion monitoring and correction is further provided, comprising:

[0043] Step 100: Obtain voltage and current signals on the electrical load leads.

[0044] Step 200: Calculate the voltage signal and the current signal to obtain component data in the current signal, and perform correction calculation based on each component data to obtain a corrected current reference value; each component data includes an unbalanced component, a reactive component, and a harmonic component.

[0045] Step 300: performing prediction based on the correction current reference value and a discrete mathematical prediction model to obtain switch action timing parameters; the discrete mathematical prediction model is constructed based on the topological structure of the electrical contact unit in a set coordinate system.

[0046] Step 400: Perform signal conditioning according to the switching action timing parameters to obtain a driving signal and a bias voltage corresponding to the switching action.

[0047] Step 500: Control the on and off of the switching element according to the driving signal and the bias voltage.

[0048] Based on this working method, in this embodiment, three through-hole current sensors are used as current sensors to measure the three-phase currents A, B, and C, respectively. Three Hall voltage sensor units are used as voltage sensors to measure the three-phase voltages A, B, and C, respectively. The output wires of the electrical contact units pass through the measurement holes of the current sensors, and the current direction from the electrical contact units to the load is defined as the positive direction. The current sensors and voltage sensors respectively measure the output current and voltage signals of the generator car through the current diversion device. These measured current and voltage signals are fed into the distortion monitoring unit. The distortion monitoring unit uses a software algorithm to calculate the unbalanced, reactive, and harmonic components in the measured current, ultimately generating a corrected current reference value.

[0049] like Figure 3 As shown, the measured current signal i al 、i bl and i cl Based on the symmetrical component method, the three-phase measured current is directly accumulated and multiplied by the coefficient 1 / 3 to obtain the zero-sequence component i0 in the power supply current. The zero-sequence component is subtracted from each phase current to obtain the three-phase current i′ after the zero-sequence component is separated. al , i′ bl and i′ cl After separating the zero-sequence component, according to the principle of symmetrical component method, the three-phase current i′ represented in the abc coordinate system is al (t), i′ bl (t) and i′ cl (t) is converted into the load current i in the α-β coordinate system α (t) and i β (t), i α (t) and i β (t) can be expressed as the sum of the positive sequence and negative sequence current, and the T / 4 delay signal separation method is used to separate i α (t) and i β (t) represents a current signal delay of T / 4, i.e. π / 2, then i α (tT / 4) and i β The positive sequence component i of the current in the expression (tT / 4) α1(t), i β1 (t) and negative sequence component i α2 (t), i β2 Based on the positive sequence component and negative sequence component of any phase, combined with the real-time phase of the positive sequence voltage e of that phase, the instantaneous active and reactive power i of the three-phase circuit can be calculated. p and i q In this embodiment, the positive and negative sequence components of phase A are used for calculation; the instantaneous active and reactive powers p and q of the circuit in the α-β coordinate system can be obtained; the instantaneous active and reactive powers can be expressed as the fundamental current i in the α-β coordinate system αj (t) and i βj (t) function, and then the fundamental wave i can be calculated by p and q αj (t) and i βj (t); finally, i αj (t) and i βj (t) Perform coordinate transformation from the α-β coordinate system to the abc coordinate system to obtain the three-phase fundamental current i in the abc coordinate system aj 、i bj and i cj , the fundamental current and the measured current i al 、i bl and i cl Subtracting the current unbalance component i az 、i bz and i cz The correction current value i can be obtained by adding the separated current unbalanced component, reactive component and harmonic component. ar 、i br and i cr ; Correct the current value i ar 、i br and i cr By inputting it into the current correction unit, the timing parameters of the power electronic switch action can be calculated.

[0050] like Figure 4 As shown, the current correction unit first constructs a discrete mathematical model of the electric contact unit in the α-β-0 coordinate based on the topological structure of the electric contact unit, and expresses the current value in the specific switch state x at the n+1th time as the output equivalent voltage U of the electric contact unit in the specific switch state x at the n+1th time. αx 、U βx 、U 0x , three-phase equivalent voltage e on the grid side αs 、e βs 、e 0s , and the corrected current value i at the nth moment αr 、i βr and i 0rA discrete mathematical prediction model is constructed based on the function of the current state. A switch state table is constructed, which is an equivalent output voltage table of all on-off state combinations of the three main switches and eight auxiliary switches of the electrical contact unit. The voltage and current at the n+1 sampling moment in the α-β-0 coordinate system, as well as the switch state table, are substituted into the discrete mathematical prediction model to predict the output current prediction value at the n+2 sampling moment and all switch states. The cost function f is constructed using the absolute value of the difference between the reference value of the corrected current output by the distortion monitoring unit at the n+2 moment and the predicted value. gx ; Select the switching state that minimizes the cost function, that is, determine the switching state corresponding to the output current closest to the reference current. The current correction unit sends the calculated switching state quantity, that is, the power electronic switch action timing parameter, to the drive unit through the wire.

[0051] After receiving the power electronic switch action timing parameters, the drive unit amplifies and conditions these parameters to generate 11 drive signals that can directly drive all power electronic switches in the electrical contact unit. The drive signals are sent to the drive electrodes of the power electronic switch devices in the electrical contact unit to drive the switch action, thereby causing the distortion correction unit to output the correction current to correct the power supply current. Figure 2 As shown, the electrical contact unit consists of 11 power electronic switches, including 3 main switches. In this embodiment, the main switches use high-power MOSFETs and are connected in series in the three-phase transmission line; and 8 auxiliary switches. In this embodiment, the auxiliary switches use fast IGBT switches.

[0052] From the specific device structure and working method provided above, it can be seen that:

[0053] The terminal drainage device is the connection link between the mobile power generation vehicle and the distribution lines and power loads. The mobile power generation vehicle must pass through the terminal drainage device to access the distribution lines to supply power to the loads. Therefore, the power generation vehicle drainage device is essentially an electrical switching element. However, the drainage device, as a switching element, is the only connection point between the power generation vehicle (power source) and the lines and power loads. If the power quality of the power supply current of the power generation vehicle is not managed at this link, the distorted current on the power supply side will enter the distribution lines and network, threatening the power safety of users. On the other hand, as a switching element, the drainage device has the characteristics of flexible and adjustable on and off operation, which provides feasibility and great convenience for monitoring and suppressing the current distortion on the power supply side of the power generation vehicle.

[0054] Currently, current distortion monitoring and correction in power systems typically focuses on the load side. Because the power supply also suffers from three-phase imbalance and current distortion, addressing the problem solely on the load side is ineffective. Furthermore, while mobile generator trucks, known for their inductive power supply technology, are a new approach to power supply security in recent years, limited research is currently focused on monitoring and optimizing the power quality of these mobile power sources.

[0055] The present embodiment provides a current distortion monitoring and correction power vehicle terminal drainage device. By adopting a current monitoring method based on the theory of instantaneous reactive power compensation, it monitors and separates the unbalanced current component, reactive component, and harmonic component during the inductive connection of the power vehicle. By adopting an algorithm strategy based on model predictive control, the drainage device is able to output a corrected current that strips out the unbalanced component, reactive component, and harmonic component, thereby suppressing the current distortion on the power supply side of the power vehicle and improving the power quality of the mobile power vehicle. That is, the drainage device is used to monitor and track the power supply waveform of the power vehicle, thereby achieving targeted elimination of abnormal components in the power supply current, effectively suppressing the distortion of the output current waveform of the power vehicle, and improving the power quality of the power vehicle.

[0056] Therefore, the advantages of the current distortion monitoring and correction terminal diversion device of the power generation vehicle of this embodiment are: (1) it can carry out current distortion monitoring and correction on the power supply side, and the power supply quality management effect of the power generation vehicle is good; (2) it uses a current waveform real-time monitoring strategy based on instantaneous reactive power theory, and only needs the phase of any phase voltage in the three-phase circuit to obtain the three-phase instantaneous active and reactive power, so that the adverse effects of voltage distortion can be minimized, the calculation complexity is greatly reduced, and the precision and accuracy of current waveform distortion monitoring are improved; (3) it uses a current distortion correction strategy based on model prediction-correction, which improves the effect of current waveform distortion correction and optimizes the correction effect; (4) it uses multiple high-power fast power electronic switching devices to form an electrical contact unit, and through the flexible opening and closing actions of the power electronic switch, it can achieve high-precision current waveform distortion correction.

[0057] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0058] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A current distortion monitoring and correction device for a power generation vehicle, characterized in that: include: Current sensor, voltage sensor, distortion monitoring unit, current correction unit, drive unit and electrical contact unit; An electric load lead is connected to the measuring terminal of the voltage sensor and passed through the measuring hole of the current sensor to be connected to the electrical contact unit. The signal output terminal of the voltage sensor and the signal output terminal of the current sensor are connected to the distortion monitoring unit. The distortion monitoring unit, the current correction unit, the drive unit and the electrical contact unit are connected in sequence. The distortion monitoring unit is used to calculate the voltage signal and current signal measured by the sensor to obtain component data in the current signal, and perform correction calculation based on each component data to obtain a correction current reference value; Each of the component data includes an unbalanced component, a reactive component and a harmonic component; The current correction unit is used to predict according to the correction current reference value and a discrete mathematical prediction model to obtain a switch action timing parameter; the discrete mathematical prediction model is constructed based on the topological structure of the electrical contact unit in a set coordinate system; The driving unit is used to perform signal conditioning according to the switching action timing parameters to obtain a driving signal and a bias voltage corresponding to the switching action; The electrical contact unit is used to control the on and off of the switch element according to the driving signal and the bias voltage.

2. The terminal current drainage device for current distortion monitoring and correction of a power generation vehicle according to claim 1 is characterized in that: The current sensor uses three through-hole current sensors, which are used to measure the three-phase currents A, B, and C respectively.

3. The terminal current drainage device for current distortion monitoring and correction of a power generation vehicle according to claim 1, characterized in that: The voltage sensor uses three Hall voltage sensor units, which are used to measure the three-phase voltages A, B, and C respectively.

4. The terminal current drainage device for current distortion monitoring and correction of a power generation vehicle according to claim 1, characterized in that: The electrical contact unit consists of 11 electrical contact switches, including 3 main switches and 8 auxiliary switches; wherein, each main switch is connected to the main circuit of the three-phase circuit, and each auxiliary switch is grouped in pairs to form 4 bridge arms, each bridge arm has two switch electrical contacts, and the lead-out wires of each switch electrical contact are respectively connected to the three-phase line and the neutral line of the main circuit.

5. The terminal current drainage device for current distortion monitoring and correction of a power generation vehicle according to claim 4, characterized in that: The main switch adopts a high-power MOSFET, and the auxiliary switch adopts a fast IGBT switch.

6. A method for operating a terminal current diversion device for a power generation vehicle for current distortion monitoring and correction, applied to a device as claimed in any one of claims 1 to 5, characterized in that: include: Acquiring voltage and current signals on the electrical load leads; Calculating the voltage signal and the current signal to obtain component data of the current signal, and performing correction calculation based on the component data to obtain a correction current reference value; Each of the component data includes an unbalanced component, a reactive component and a harmonic component; Predicting according to the correction current reference value and a discrete mathematical prediction model to obtain a switch action timing parameter; the discrete mathematical prediction model is constructed based on the topological structure of the electrical contact unit in a set coordinate system; Performing signal conditioning according to the switching action timing parameters to obtain a drive signal and a bias voltage corresponding to the switching action; The on and off of the switching element is controlled according to the driving signal and the bias voltage.

7. The operating method of the power generation vehicle terminal drainage device for current distortion monitoring and correction according to claim 6 is characterized in that: The calculation process of the correction current reference value is: Set current signal i al 、i bl and i cl Based on the symmetrical component method, the three-phase measured current is directly accumulated and multiplied by the coefficient 1 / 3 to obtain the zero-sequence component i0 in the power supply current. The zero-sequence component is subtracted from each phase current to obtain the three-phase current i′ after the zero-sequence component is separated. al , i′ bl and i′ cl After separating the zero-sequence component, according to the principle of symmetrical component method, the three-phase current i′ represented in the abc coordinate system is al (t), i′ bl (t) and i′ cl (t) is converted into the load current i in the α-β coordinate system α (t) and i β (t), load current i α (t) and i β (t) is expressed as the sum of the positive sequence and negative sequence currents, and the load current i is separated by T / 4 delay signal separation method. α (t) and i β (t) represents the current signal delay T / 4, then i α (tT / 4) and i β The positive sequence component i of the current in the expression (tT / 4) α1 (t), i β1 (t) and negative sequence component i α2 (t), i β2 (t) being separated; Based on the positive sequence component and negative sequence component of any phase, combined with the real-time phase of the corresponding phase positive sequence voltage e, the instantaneous active power i of the three-phase circuit is calculated. p and instantaneous reactive power i q ; Then we can get the instantaneous active power p and instantaneous reactive power q of the circuit in the α-β coordinate system; the instantaneous active power and instantaneous reactive power are expressed as the fundamental current i in the α-β coordinate system αj (t) and i βj (t) function, and then calculate the fundamental wave i through p and q αj (t) and i βj (t); finally, i ɑj (t) and i βj (t) Perform coordinate transformation from the α-β coordinate system to the abc coordinate system to obtain the three-phase fundamental current i in the abc coordinate system aj 、i bj and i cj , the fundamental current and the measured current i al 、i bl and i cl Subtract and get the current unbalance component i az 、i bz and i cz ; Add the separated current unbalanced components, reactive components and harmonic components to obtain the corrected current value i ar 、i br and i cr .

8. The operating method of the power generation vehicle terminal drainage device for current distortion monitoring and correction according to claim 6 is characterized in that: The calculation process of the switching action timing parameters is as follows: Firstly, a discrete mathematical model of the electrical contact unit in the α-β-0 coordinate is constructed based on the topological structure of the electrical contact unit. The current value in the specific switch state x at the n+1th moment is expressed as the output equivalent voltage U of the electrical contact unit in the specific switch state x at the n+1th moment. ɑx 、U βx 、U 0x , three-phase equivalent voltage e on the grid side αs 、e βs 、e 0s , and the corrected current value i at the nth moment αr 、i βr and i 0r function, and construct a discrete mathematical prediction model and a switch state table; the switch state table includes an equivalent output voltage table of all on-off state combinations of the three main switches and eight auxiliary switches of the electrical contact unit; Substitute the voltage and current at the n+1 sampling moment in the α-β-0 coordinate system and the switch state table into the discrete mathematical prediction model to predict the output current prediction value at the n+2 sampling moment and all switch states; use the absolute value of the difference between the correction current reference value and the predicted value output by the distortion monitoring unit at the n+2 moment to construct the cost function f gx ; Select the switch state that makes the cost function take the minimum value, determine the switch state quantity corresponding to the output current closest to the reference current, and obtain the switch action timing parameters.

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