Rail vehicle and its heating control system and method

Abstract

The application discloses a rail vehicle and a heating control system and method thereof, the system comprising a temperature sensor, a control module and a variable frequency power supply module, the temperature sensor being electrically connected with an input end of the control module, the input end of the control module being further communicatively connected with an air conditioner controller or a vehicle control unit, and an output end of the control module being electrically connected with an input end of the variable frequency power supply module; the driving voltage output by the variable frequency power supply module is accurately controlled according to the difference between the heating temperature setting instruction and the actual temperature in the vehicle compartment, the heating device outputs the heating capacity in proportion to the driving voltage, the heating capacity output by the heating device is matched with the heating load, the comfort is improved, and the energy is saved; the driving power supply of the heating device adopts the variable frequency power supply module, the soft start of the heating device is realized by using the variable frequency control, and the impact on the vehicle auxiliary power supply or the power grid is avoided.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of vehicle heating design, and particularly relates to a rail vehicle and a heating control system and method thereof. BACKGROUND

[0002] At present, the electric heating heating device of the rail vehicle at home and abroad generally has two gears (two groups of electric heating pipes or other heating elements are adopted), and the opening and closing of the heating elements are controlled by the contactor of the air conditioning control system to change the heating power, so as to realize the semi-warm and full-warm control. However, this control mode has the following disadvantages:

[0003] 1. The heating capacity output by the heating device does not match the heating load, and the comfort is poor. When the output heating capacity is less than the heating load, the temperature in the car is low; when the output heating capacity is greater than the heating load, the temperature in the car is high, the heating device is frequently started and stopped, the temperature in the car fluctuates greatly, and the comfort in the car is poor.

[0004] 2. The heating capacity output by the heating device cannot be linearly adjusted, the device is frequently started and stopped, the switching loss is large, and energy saving is not achieved.

[0005] In order to solve the above problems of the existing electric heating control mode of the rail transit vehicle, and realize energy saving, it is urgent to develop a heating control system to improve the heating comfort of the vehicle while realizing energy saving. SUMMARY

[0006] The purpose of the present application is to provide a rail vehicle and a heating control system and method thereof, so as to solve the problems that the existing heating control mode adopts semi-warm and full-warm control, cannot realize linear regulation of heating capacity, leads to poor comfort, frequent start and stop, large switching loss, and energy saving is not achieved.

[0007] The present application solves the above technical problems through the following technical scheme: a rail vehicle heating control system, comprising:

[0008] At least one temperature sensor, which is arranged in the car and is used to collect the actual temperature in the car;

[0009] A control module is used to obtain a heating temperature setting instruction and an actual temperature in the car, and output different control instructions according to the difference between the heating temperature setting instruction and the actual temperature;

[0010] A variable frequency power supply module, whose output end is electrically connected with the heating device, and the variable frequency power supply module is used to output different driving voltages under the control of different control instructions, so as to realize the control of the heating capacity output by the heating device and the driving voltage in a proportional manner.

[0011] Further, the temperature sensor is multiple, and the multiple temperature sensors are arranged uniformly above the ceiling of the car and / or below the seat, and the actual temperature in the car is equal to the average of the temperatures collected by the multiple temperature sensors.

[0012] Preferably, the temperature sensor is an NTC type temperature sensor.

[0013] Further, the control module is a single microcomputer controller, or the control module is an air conditioner controller.

[0014] Preferably, the power supply end of the control module is electrically connected with an external power supply through a first wiring terminal row.

[0015] Further, the control module is built-in with a network card, and the control module communicates with a vehicle TCMS system through the network card.

[0016] Further, the driving voltage range output by the variable frequency power supply module is AC 152V-AC 380V, and the corresponding frequency range is 20Hz-50Hz.

[0017] Further, the heating device is arranged below the side wall of the railway vehicle and arranged discontinuously or continuously.

[0018] Preferably, the heating device comprises an outer cover plate, an electric heating element arranged in the outer cover plate, and a mounting bracket for mounting the electric heating element.

[0019] Further, when the heating device is arranged discontinuously, the output end of the variable frequency power supply module is electrically connected with different heating devices through a second wiring terminal row.

[0020] Based on the same inventive concept, the application further provides a railway vehicle heating control method applied to a control module, wherein the input end of the control module is electrically connected with a temperature sensor arranged in a car, the output end of the control module is electrically connected with the input end of a variable frequency power supply module, and the output end of the variable frequency power supply module is electrically connected with the input end of a heating device, and the method comprises the following steps:

[0021] Obtaining the actual temperature in the car and a heating temperature setting instruction;

[0022] Calculating the difference between the heating temperature setting instruction and the actual temperature in the car;

[0023] Controlling the driving voltage output by the variable frequency power supply module according to the difference;

[0024] Controlling the heating device to output a heating capacity proportional to the driving voltage according to the driving voltage.

[0025] Further, when Tic-Tim≥4℃, the driving voltage output by the variable frequency power module is the rated voltage, and the heating output by the heating device is the nominal heating output; wherein Tic is a heating temperature setting instruction, and Tim is an actual temperature in the vehicle compartment;

[0026] When 2℃≤Tic-Tim<4℃, the driving voltage output by the variable frequency power module is 0.9*the rated voltage, and the heating output by the heating device is 0.9*the nominal heating output;

[0027] When 1.5℃≤Tic-Tim<2℃, the driving voltage output by the variable frequency power module is 0.8*the rated voltage, and the heating output by the heating device is 0.8*the nominal heating output;

[0028] When 1℃≤Tic-Tim<1.5℃, the driving voltage output by the variable frequency power module is 0.7*the rated voltage, and the heating output by the heating device is 0.7*the nominal heating output;

[0029] When 0.5℃≤Tic-Tim<1℃, the driving voltage output by the variable frequency power module is 0.6*the rated voltage, and the heating output by the heating device is 0.6*the nominal heating output;

[0030] When 0℃≤Tic-Tim<0.5℃, the driving voltage output by the variable frequency power module is 0.5*the rated voltage, and the heating output by the heating device is 0.5*the nominal heating output;

[0031] When -0.5℃≤Tic-Tim<0℃, the driving voltage output by the variable frequency power module is 0.4*the rated voltage, and the heating output by the heating device is 0.4*the nominal heating output;

[0032] When -1℃≤Tic-Tim<-0.5℃, the driving voltage output by the variable frequency power module is 0, and the heating device is closed.

[0033] Based on the same inventive concept, the application further provides a rail vehicle comprising the rail vehicle heating control system as described above.

[0034] Advantages

[0035] Compared with the prior art, the application has the following advantages:

[0036] The rail vehicle and the heating control system and method thereof provided by the application can accurately control the driving voltage outputted by the variable frequency power module according to the difference between the heating temperature setting instruction and the actual temperature in the carriage, and the heating device outputs the heating capacity in proportion to the driving voltage, so that the heating capacity outputted by the heating device is matched with the heating load, the comfort is improved, and the energy is saved; the driving power source of the heating device adopts the variable frequency power module, and the soft start of the heating device is realized by using the variable frequency control, so that the impact on the vehicle auxiliary power source or the power grid is avoided.

[0037] The application can steplessly adjust the driving voltage and frequency outputted by the variable frequency power module, so that the stepless adjustment of the heating capacity outputted by the heating device is realized, when a single heating device works, the heating capacity thereof can be steplessly adjusted in the range of 40% to 100% of the nominal heating capacity, when multiple heating devices work together, the heating capacity adjustment range of a single section of the vehicle is wider (adjustable in the range of 4% to 100%), and the comfort of the vehicle heating is greatly improved. BRIEF DESCRIPTION OF DRAWINGS

[0038] In order to more clearly illustrate the technical solutions of the application, the drawings needed in the following embodiment description will be briefly introduced. Obviously, the drawings in the following description are only one embodiment of the application, and other drawings can be obtained by those skilled in the art without creative effort.

[0039] Figure 1 is the structure block diagram of the rail vehicle heating control system in the embodiment of the application;

[0040] Figure 2 is the arrangement diagram of the heating device, the temperature sensor and the control module in the embodiment of the application;

[0041] Figure 3 is the A-A sectional view of Figure 2 in the embodiment of the application;

[0042] Figure 4 is the B-B sectional view of Figure 2 in the embodiment of the application;

[0043] Figure 5 is the C-C sectional view of Figure 2 in the embodiment of the application;

[0044] Figure 6 is the arrangement diagram of the rail vehicle heating control system in the embodiment of the application;

[0045] Figure 7 is the composition diagram of the heating device in the embodiment of the application;

[0046] Figure 8is a flow chart of a heating control method of a rail vehicle in the embodiment of the present application.

[0047] Wherein, 1-first wiring terminal row, 2-control module, 3-variable frequency power supply module, 4-second wiring terminal row, 5-metal framework, 6-heating device, 61-outer cover plate, 62-electric heating element, 63-mounting bracket, 7-heating control system (pointing to Figure 1 each module in the dashed box), 8-temperature sensor. DETAILED DESCRIPTION

[0048] The technical solutions in the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0049] The technical solutions of the present application will be described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and some embodiments may not be described again for the same or similar concepts or processes.

[0050] As shown in the figure, the heating control system of the rail vehicle provided in the present embodiment comprises a temperature sensor, a control module and a variable frequency power supply module. The temperature sensor is electrically connected with the input end of the control module. The input end of the control module is also communicatively connected with an air conditioner controller or a vehicle control unit. The output end of the control module is electrically connected with the input end of the variable frequency power supply module. Figure 1 The temperature sensor is arranged in the vehicle compartment and is used to collect the actual temperature in the vehicle compartment. In the present embodiment, the temperature sensor is selected to be an NTC type temperature sensor, and there are multiple temperature sensors. The multiple temperature sensors are uniformly arranged above the ceiling of the vehicle compartment and / or in the seat arrangement area. For example, as shown in the figure, seven temperature sensors 8 are arranged in each vehicle, which are uniformly arranged in the length direction, width direction and height direction of the seat arrangement area of the vehicle. The temperature sampling points are representative and have redundancy. When a temperature sensor corresponding to a certain temperature sampling point fails, the control module takes the temperature value of a similar sampling point. If there is no failure, the average value of multiple temperature sampling points is taken. When there are multiple temperature sensors 8, the actual temperature in a single vehicle compartment is equal to the average value of the temperatures collected by the multiple temperature sensors 8 in the vehicle compartment.

[0051] Figures 2 to 5

[0052] ​​The control module receives the actual temperature inside the passenger compartment from the temperature sensor according to the sampling period, as well as the heating temperature setting command sent by the air conditioning controller or vehicle control unit. It calculates the difference between the heating temperature setting command and the actual temperature inside the passenger compartment, and outputs different control commands based on the difference and different setting thresholds. The control module can be a standalone microcomputer controller or shared with other controllers (such as the air conditioning controller).

[0053] Under the different control commands of the control module, the frequency converter power supply module outputs different drive voltages to the heating devices in the corresponding carriages. The heating devices output heat output proportional to the drive voltage according to the different drive voltages, thus realizing the matching control of the heat output of the heating devices with the heating load.

[0054] The variable frequency power supply module can adopt various power input standards, such as AC380V, DC1500V, or DC750V, or other power standards. The output drive voltage range of the variable frequency power supply module is AC152V to AC380V, corresponding to a frequency range of 20Hz to 50Hz. In this embodiment, the variable frequency power supply module includes a high-precision microcontroller and a variable frequency IPM module to realize DC-AC variable frequency output control. The variable frequency power supply module controls the output of the variable frequency IPM module according to the heating demand, thus realizing variable frequency output control. The variable frequency IPM module has output phase loss protection, overvoltage and undervoltage protection, as well as IPM overcurrent and overheat protection.

[0055] The heating control system also includes a first terminal block 1 and a second terminal block 4. The power supply terminal of the control module 2 is electrically connected to an external power source through the first terminal block 1, and the output terminal of the frequency converter module 3 is electrically connected to the heating device 6 through the second terminal block 4. The heating control system can be installed inside the vehicle's control cabinet or in a roof-mounted equipment box (e.g., for air conditioning). Figure 6 The diagram shows the layout of the components of the heating control system. The control module 2 and the variable frequency power supply module 3 are arranged on the metal frame 5. A first terminal block 1 is provided on one side of the control module 2, and a second terminal block 4 is provided on one side of the variable frequency power supply module 3, which facilitates the connection of the control system with external power supply and heating device.

[0056] like Figure 7 As shown, the heating device includes an outer cover plate 61, an electric heating element 62 disposed within the outer cover plate 61, and a mounting bracket 63 for mounting the electric heating element 62. The rated input voltage (or supply voltage) of a single heating device is three-phase AC380V, and its input voltage adaptability range is wide, allowing it to operate normally within the range of AC150V to AC380V.

[0057] like Figure 2As shown, the heating device 6 is arranged below the side wall of the rail vehicle, and can be arranged flexibly according to the arrangement of seats and equipment inside the vehicle, and can be arranged discontinuously or continuously, and can be applied to various vehicle types. When the heating device 6 is arranged discontinuously, multiple heating devices 6 are arranged in each vehicle compartment, and the multiple heating devices 6 are electrically connected to the output end of the frequency conversion power module respectively. For example, as shown in the figure, Figures 2 to 5 As shown, 7 heating devices 6 are arranged in each vehicle compartment, and the 7 heating devices 6 are arranged in the seat area and are matched with the seat structure of the vehicle, so as to ensure the comfort of passengers in winter heating.

[0058] The temperature sensor is used for monitoring the temperature in the vehicle compartment; the control module adjusts the heating amount output by the heating device according to the temperature in the vehicle compartment, so as to realize temperature control; the circuit breaker is used for realizing short circuit protection; the heating control system performs self-checking each time it is started, and feeds back the self-checking result to the control module. The heating control system of the present application takes the control module as the core, cooperates with the circuit breaker, the contactor, the temperature sensor and other elements, the circuit breaker and the contactor are both provided with feedback contacts, and the temperature control, fault diagnosis and protection and other functions of the heating device can be completed. The MVB network card or the Ethernet card is installed in the control system, and is used for communication between the control module and the TCMS system of the vehicle.

[0059] As shown in the figure, Figure 8 The present embodiment also provides a rail vehicle heating control method, which is applied to the control module, the input end of the control module is electrically connected to the temperature sensor arranged in the vehicle compartment, the output end of the control module is electrically connected to the input end of the frequency conversion power module, and the output end of the frequency conversion power module is electrically connected to the input end of the heating device, and the method comprises the following steps:

[0060] Step 1: The control module acquires the actual temperature in the vehicle compartment collected by the temperature sensor and the heating temperature setting instruction sent by the vehicle control unit or the air conditioner controller.

[0061] The temperature sensor is arranged in the vehicle compartment and is used for collecting the actual temperature in the vehicle compartment. In the present embodiment, the temperature sensor is selected from NTC type temperature sensors, and the temperature sensor comprises multiple temperature sensors, and the multiple temperature sensors are arranged uniformly above the ceiling of the vehicle compartment and / or below the seats. When the temperature sensor has multiple temperature sensors, the actual temperature in a single vehicle compartment is equal to the average value of the temperatures collected by the multiple temperature sensors in the vehicle compartment.

[0062] The heating temperature setting instruction is the target heating temperature.

[0063] Step 2: The control module calculates the difference between the heating temperature setting instruction and the actual temperature in the vehicle compartment.

[0064] Step 3: The control module controls the driving voltage output by the frequency conversion power module according to the difference and different setting threshold values.

[0065] Step 4: According to the driving voltage, the heating device outputs the heating capacity proportional to the driving voltage.

[0066] In this embodiment, let Tic be the heating temperature setting instruction, Tim be the actual temperature in the vehicle cabin, the rated voltage of the variable frequency power module be 380V, and the specific control strategy be:

[0067] When Tic-Tim≥4℃, the driving voltage output by the variable frequency power module is 380V, and the heating capacity output by the heating device is the nominal heating capacity, i.e., full warm operation;

[0068] When 2℃≤Tic-Tim<4℃, the driving voltage output by the variable frequency power module is 0.9*380V, and the heating capacity output by the heating device is 0.9*the nominal heating capacity;

[0069] When 1.5℃≤Tic-Tim<2℃, the driving voltage output by the variable frequency power module is 0.8*380V, and the heating capacity output by the heating device is 0.8*the nominal heating capacity;

[0070] When 1℃≤Tic-Tim<1.5℃, the driving voltage output by the variable frequency power module is 0.7*380V, and the heating capacity output by the heating device is 0.7*the nominal heating capacity;

[0071] When 0.5℃≤Tic-Tim<1℃, the driving voltage output by the variable frequency power module is 0.6*380V, and the heating capacity output by the heating device is 0.6*the nominal heating capacity;

[0072] When 0℃≤Tic-Tim<0.5℃, the driving voltage output by the variable frequency power module is 0.5*380V, and the heating capacity output by the heating device is 0.5*the nominal heating capacity, i.e., half warm operation;

[0073] When -0.5℃≤Tic-Tim<0℃, the driving voltage output by the variable frequency power module is 0.4*380V, and the heating capacity output by the heating device is 0.4*the nominal heating capacity;

[0074] When -1℃≤Tic-Tim<-0.5℃, the driving voltage output by the variable frequency power module is 0, and the heating device is closed.

[0075] According to the control strategy as above, the heating capacity of a single heating device can be steplessly adjusted in the range of 40% to 100% of the nominal heating capacity. The coefficients 0.9, 0.8, 0.7, 0.6, 0.5, 0.4 and the set threshold values 4℃, 2℃, 1.5℃, 1℃, 0.5℃, 0℃, -0.5℃, -1℃ can be adjusted according to the actual situation, the more precise the coefficients and the set threshold values are set, the more accurate the driving voltage and the output heating capacity control are, and the linear adjustment of the heating capacity can be realized. The nominal heating capacity is the heating capacity marked on the product nameplate, which is measured under a certain fixed working condition.

[0076] The above only discloses specific embodiments of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of changes or modifications within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A rail vehicle heating control system, characterized in that, The system comprises: at least one temperature sensor arranged in the vehicle cabin and used for collecting the actual temperature in the vehicle cabin; a control module used for obtaining the heating temperature setting instruction and the actual temperature in the vehicle cabin, and outputting different control instructions according to the difference between the heating temperature setting instruction and the actual temperature; a variable frequency power supply module, the input end of which is connected with the auxiliary power supply of the vehicle, and the output end of which is electrically connected with the heating device, the variable frequency power supply module comprising a high-precision single-chip microcomputer and a variable frequency IPM module, and being used for converting the input voltage of the auxiliary power supply of the vehicle into a driving voltage of AC 152V-AC 380V, 20Hz-50Hz under the control of different control instructions; wherein, the system is configured to adjust the driving voltage by the variable frequency power supply module, so that the heating capacity output by the heating device is in a proportional relationship with the driving voltage, and stepless adjustment can be realized in the range of 40% to 100% of the nominal heating capacity of a single heating device, thereby realizing the matching control of the heating capacity and the heating load; when Tic-Tim≥4℃, the driving voltage output by the variable frequency power supply module is the rated voltage, and the heating capacity output by the heating device is the nominal heating capacity; wherein, Tic is the heating temperature setting instruction, and Tim is the actual temperature in the vehicle cabin; when 2℃≤Tic-Tim<4℃, the driving voltage output by the variable frequency power supply module is 0.9*the rated voltage, and the heating capacity output by the heating device is 0.9*the nominal heating capacity; when 1.5℃≤Tic-Tim<2℃, the driving voltage output by the variable frequency power supply module is 0.8*the rated voltage, and the heating capacity output by the heating device is 0.8*the nominal heating capacity; when 1℃≤Tic-Tim<1.5℃, the driving voltage output by the variable frequency power supply module is 0.7*the rated voltage, and the heating capacity output by the heating device is 0.7*the nominal heating capacity; when 0.5℃≤Tic-Tim<1℃, the driving voltage output by the variable frequency power supply module is 0.6*the rated voltage, and the heating capacity output by the heating device is 0.6*the nominal heating capacity; when 0℃≤Tic-Tim<0.5℃, the driving voltage output by the variable frequency power supply module is 0.5*the rated voltage, and the heating capacity output by the heating device is 0.5*the nominal heating capacity; when -0.5℃≤Tic-Tim<0℃, the driving voltage output by the variable frequency power supply module is 0.4*the rated voltage, and the heating capacity output by the heating device is 0.4*the nominal heating capacity; when -1℃≤Tic-Tim<-0.5℃, the driving voltage output by the variable frequency power supply module is 0, and the heating device is closed.

2. The rail vehicle heating control system of claim 1, wherein: The temperature sensor has multiple temperature sensors, and the multiple temperature sensors are arranged uniformly above the ceiling and / or below the seat in the vehicle cabin, and the actual temperature in the vehicle cabin is equal to the average of the temperatures collected by the multiple temperature sensors.

3. The rail vehicle heating control system of claim 1, wherein: The control module is a separate microcomputer controller, or the control module is an air conditioner controller. The power supply end of the control module is electrically connected with the external power supply through the first wiring terminal block.

4. A rail vehicle heating control system according to claim 1 or 3, characterised in that: The control module is internally provided with a network card, and the control module communicates with the TCMS system of the vehicle through the network card.

5. The rail vehicle heating control system of claim 1, wherein: The heating device is arranged below the side wall of the railway vehicle and is arranged in a discontinuous or continuous manner.

6. The railcar heating control system of claim 1, wherein: The heating device comprises an outer cover plate, an electric heating element arranged in the outer cover plate, and a mounting bracket for mounting the electric heating element.

7. A rail vehicle heating control system according to claim 1 or 5, characterised in that: When the heating device is arranged in a discontinuous manner, the output end of the variable frequency power module is electrically connected to different heating devices through a second wiring terminal block.

8. A rail vehicle heating control method applied to a control module, characterized in that, The input end of the control module is electrically connected to a temperature sensor arranged in the vehicle compartment, the output end of the control module is electrically connected to the input end of the variable frequency power module, the input end of the variable frequency power module is connected to the auxiliary power supply of the vehicle, the output end of the variable frequency power module is electrically connected to the input end of the heating device, the variable frequency power module comprises a high-precision single-chip microcomputer and a variable frequency IPM module, and the method comprises the following steps: acquiring an actual temperature in the vehicle compartment and a heating temperature setting instruction; calculating a difference between the heating temperature setting instruction and the actual temperature in the vehicle compartment; controlling the variable frequency power module to convert the input voltage of the auxiliary power supply of the vehicle into a driving voltage of AC 152 V-AC 380 V, 20 Hz-50 Hz according to the difference; controlling the heating device to output a heating capacity proportional to the driving voltage according to the driving voltage, and enabling stepless linear regulation within 40% to 100% of the nominal heating capacity of a single heating device, thereby realizing matching control of the heating capacity output by the heating device and the heating load and soft start of the heating device; when Tic-Tim is greater than or equal to 4℃, the driving voltage output by the variable frequency power module is a rated voltage, and the heating capacity output by the heating device is a nominal heating capacity; wherein Tic is the heating temperature setting instruction, and Tim is the actual temperature in the vehicle compartment; when 2℃≤Tic-Tim<4℃, the driving voltage output by the variable frequency power module is 0.9*the rated voltage, and the heating capacity output by the heating device is 0.9*the nominal heating capacity; when 1.5℃≤Tic-Tim<2℃, the driving voltage output by the variable frequency power module is 0.8*the rated voltage, and the heating capacity output by the heating device is 0.8*the nominal heating capacity; when 1℃≤Tic-Tim<1.5℃, the driving voltage output by the variable frequency power module is 0.7*the rated voltage, and the heating capacity output by the heating device is 0.7*the nominal heating capacity; when 0.5℃≤Tic-Tim<1℃, the driving voltage output by the variable frequency power module is 0.6*the rated voltage, and the heating capacity output by the heating device is 0.6*the nominal heating capacity; when 0℃≤Tic-Tim<0.5℃, the driving voltage output by the variable frequency power module is 0.5*the rated voltage, and the heating capacity output by the heating device is 0.5*the nominal heating capacity; when -0.5℃≤Tic-Tim<0℃, the driving voltage output by the variable frequency power module is 0.4*the rated voltage, and the heating capacity output by the heating device is 0.4*the nominal heating capacity; When -1℃≤Tic-Tim< -0.5℃, the driving voltage output by the variable frequency power module is 0, and the heating device is closed.

9. A rail vehicle, characterized by: The rail vehicle heating control system according to any one of claims 1-7.

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