Method for controlling sewage recycling or discharging of new energy pure electric cleaning and sweeping vehicle

Abstract

The invention belongs to the technical field of environmental sanitation vehicle control, and particularly relates to a new energy pure electric cleaning and sweeping vehicle sewage recycling or discharging control method which aims at solving the problems that an existing cleaning and sweeping vehicle is high in water adding and sewage discharging frequency and large in power consumption due to ineffective load, and the weight is monitored in real time through weight sensors of a clear water tank and a sewage tank; and in combination with a water level signal of the sewage tank, the sewage purification and waterway transmission controller and the vehicle control unit make a decision collaboratively. When the water in the clear water tank is insufficient and the sewage tank meets the condition, the purification device is automatically started to supplement the treated clear water into the clear water tank; and when the clear water tank is full and the sewage tank still has residual liquid, the drainage mode is automatically switched to. According to the system, intelligent cyclic utilization and discharge of sewage are achieved, the external source water supplementing frequency and the invalid bearing weight are remarkably reduced, and therefore the operation efficiency is improved, the vehicle energy consumption is reduced, and the endurance mileage is prolonged.

Description

Technical Field

[0001] This invention relates to the field of sanitation vehicle control technology, and in particular to a control method for the recycling or discharge of sewage from a new energy pure electric sweeper. Background Technology

[0002] With the popularization of new energy technologies in the field of special vehicles, pure electric sweeper trucks have been widely used in urban sanitation operations due to their advantages such as zero emissions and low noise. A typical pure electric sweeper truck is usually equipped with a clean water tank and a sewage tank. Its traditional working mode is as follows: after the clean water tank is filled with clean water, the sweeping operation begins. After the clean water is exhausted, it needs to return to a fixed water station to replenish the water. At the same time, the sewage collected during the operation is stored in the sewage tank. After the sewage tank is full, it needs to drive to a designated sewage discharge point or find a suitable location for discharge.

[0003] This traditional operating model has significant drawbacks: First, the frequent water filling and sewage discharge processes consume a significant amount of effective working time. For vehicles with a load capacity of 18 tons, the daily water filling time may account for a quarter of the total working time, severely reducing the continuity and overall efficiency of sanitation operations.

[0004] Secondly, vehicles often operate under suboptimal load conditions. For example, when refilling the fresh water tank, the vehicle may still be carrying a fully loaded wastewater tank; or when heading to a sewage discharge point with a full wastewater tank, the vehicle may be carrying the remaining fresh water. This "ineffective load" significantly increases the drive load on the motor, leading to unnecessary energy consumption, shortening the vehicle's range per charge, and potentially increasing the number of daily charging sessions or requiring a larger capacity battery pack, thus driving up operating and manufacturing costs.

[0005] Therefore, there is an urgent need for a control method that can intelligently manage the water tank system of sweeper trucks, realize the recycling of sewage, dynamically adjust the weight of the vehicle, and thus improve operating efficiency and energy utilization. Summary of the Invention

[0006] Based on the technical problems existing in the prior art, this invention proposes a control method for the recycling or discharge of sewage from a new energy pure electric sweeper.

[0007] This invention proposes a control method for the recycling or discharge of wastewater from a new energy pure electric sweeper truck. The sweeper truck includes at least a clean water tank, a wastewater tank, a wastewater purification device and pipeline system connecting the wastewater tank and the clean water tank, a high-voltage power supply system for powering the purification device, a clean water tank weight sensor, a wastewater tank weight sensor, a wastewater tank water level sensor, a wastewater purification and water transmission controller, and a vehicle controller.

[0008] The control method includes the following steps: Step S1: System Initialization The initial weight M1 of the clean water tank when fully loaded with clean water and the initial weight M2 of the sewage tank when unloaded are calibrated, and M1 and M2 are stored in the system of the sewage purification and water transmission controller.

[0009] Step S2: Monitoring and triggering judgment of the status of the clean water tank The current weight of the clean water tank is collected in real time by a weight sensor and sent to the wastewater purification and water transmission controller. The controller compares the received real-time weight with a first threshold (0.8*M1). If the real-time weight is less than or equal to the first threshold for a first preset duration (e.g., 5 seconds), a low water level trigger signal for the clean water tank is generated.

[0010] If the real-time weight exceeds the first preset time for a continuous period of time, a high water level standby signal for the clean water tank will be generated.

[0011] Step S3: Wastewater tank status monitoring and trigger judgment The current weight of the sewage tank is collected in real time by a sewage tank weight sensor and sent to the sewage purification and water transmission controller. The controller compares the received real-time weight with a second threshold (1.2*M2) and simultaneously monitors the signal from the sewage tank water level sensor. If the real-time weight is greater than or equal to the second threshold for a second preset duration (e.g., 5 seconds) and a water level sensor signal is received, a wastewater tank purification trigger signal is generated.

[0012] If the real-time weight is continuously greater than or equal to the second threshold for a second preset duration, but no water level sensor signal is received, a sewage tank purification prohibition signal is generated.

[0013] If the real-time weight is less than the second threshold for a second consecutive preset time and a water level sensor signal is received, a wastewater tank purification trigger signal is generated.

[0014] If the real-time weight is less than the second threshold for a second consecutive preset time and no water level sensor signal is received, a sewage tank purification prohibition signal will be generated.

[0015] Step S4: Integrated Decision-Making and Execution Control The judgment results of steps S2 and S3 of the wastewater purification and water transmission controller are communicated with the vehicle controller via the CAN bus to coordinate decision-making and control the actions of the high-voltage power supply system and the wastewater purification and pipeline system. When both the "low water level trigger" and "purification trigger" conditions are met simultaneously, the vehicle controller instructs the high-voltage power supply system to power the sewage purification device, start the sewage purification process, and fill the clean water tank with water until the real-time weight of the clean water tank reaches or approaches M1.

[0016] If the status of the wastewater tank changes to "purification prohibited" during the filling process of the clean water tank, the purification and filling process will stop.

[0017] When the conditions of "high water level standby in the clean water tank" (i.e., weight > 0.8 * M1) and "purification trigger in the wastewater tank" are met, the vehicle controller can also instruct the wastewater purification device to start filling the clean water tank with water until the clean water tank is full (weight ≥ M1). If the wastewater tank is still in the "purification trigger" state at this time, the controller controls the pipeline system to switch to the sewage discharge mode through a hard-wired signal to discharge the residual liquid in the wastewater tank (which may be purified water or unpurified bottom sludge liquid) until the water level sensor outputs no signal.

[0018] When the clean water tank is at a low water level but the wastewater tank is in a "purification prohibited" state, the system will not start the purification process and will prompt the operator to perform routine water replenishment or check the status of the wastewater tank.

[0019] The system remains in standby mode when the clean water tank is in a high water level standby state and the wastewater tank is in a "purification prohibited" state.

[0020] Preferably, the wastewater purification device includes at least one of a multi-stage filtration unit and a physicochemical purification unit to remove solid particles, suspended solids and some dissolved pollutants from the wastewater, so that it meets the reuse standards for washing and sweeping water.

[0021] Preferably, the pipeline system includes an inlet pipeline connecting the sewage tank and the purification device, a reuse pipeline connecting the purification device and the clean water tank, and an outlet pipeline connecting the sewage tank or the end of the purification device. Each pipeline is equipped with a solenoid valve or electric valve controlled by a controller to achieve the switching of water flow paths.

[0022] Preferably, the weight sensor for the clean water tank and the weight sensor for the wastewater tank are weighing sensors installed on the tank support structure; the water level sensor for the wastewater tank is a float-type, capacitive, or ultrasonic level sensor.

[0023] Compared with the prior art, the present invention provides a control method for the recycling or discharge of wastewater from a new energy pure electric sweeper truck, which has the following beneficial effects: 1. Improved operational efficiency: By recycling wastewater, the number of times and time required for sweepers to refill clean water at fixed stations are significantly reduced, increasing the effective daily operating time and operating area of ​​a single vehicle.

[0024] 2. Optimize energy consumption and range: Through dynamic control, the vehicle avoids being in the heaviest state of "empty water tank" and "full sewage tank" at the same time during most of the working time, and maintains the working weight of the vehicle in a relatively better range, reducing the average power consumption during driving and operation, thereby effectively extending the range of a single charge.

[0025] 3. Achieve water resource recycling: The collected sewage is purified and reused, saving precious clean water resources and meeting the requirements of environmental protection and sustainable development.

[0026] 4. Intelligence and Automation: The entire control process is based on automatic decision-making and execution using sensor data, which reduces driver intervention, lowers operational complexity, and improves the overall intelligence level of the vehicle.

[0027] 5. Optimized discharge control: When the clean water tank is full and the wastewater tank still contains liquid, the system can automatically start the discharge process, which avoids excessive accumulation of sediment in the wastewater tank and can use clean water to rinse the tank during discharge, thus improving the cleanliness of the system. Attached Figure Description

[0028] Figure 1 This is the logic flowchart proposed in this invention. Detailed Implementation

[0029] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0030] Example 1: This example provides a pure electric sweeper truck that uses the control method of the present invention. The vehicle includes a chassis, a superstructure working mechanism, a power battery system, a drive system, and a water tank system consisting of a clean water tank and a wastewater tank.

[0031] A first weighing sensor is installed at the bottom of the clean water tank or on the support beam to monitor the total weight of the clean water tank and its internal liquid in real time. A second weighing sensor is installed at the bottom of the sewage tank or on the support beam to monitor the total weight of the sewage tank and its internal waste in real time. A float-type water level sensor is also installed inside the sewage tank to detect whether there is enough liquid stored in the tank (regardless of whether it contains solid residue).

[0032] The outlet of the sewage tank is connected to a sewage purification and piping system. This system mainly includes a multi-stage filtration and purification device (i.e., sewage purification device) consisting of a primary filter, a hydrocyclone separator, and a precision filter, as well as fluid transport components consisting of pipelines, a water pump, and a three-position four-way solenoid valve. The inlet of the system is connected to the sewage tank, its first outlet can be connected to the inlet of the clean water tank through a reuse pipeline, and its second outlet can be connected to the sewage outlet at the rear of the vehicle through a discharge pipeline. The system's operating mode (purification and reuse mode or direct discharge mode) is controlled by switching the solenoid valve.

[0033] The vehicle is equipped with a dedicated sewage purification and water transmission controller (hereinafter referred to as "U controller"). The first weighing sensor, the second weighing sensor, and the water level sensor are all connected to the U controller through a low-voltage wiring harness, which transmits the collected weight analog signal or digital switch signal to the U controller. The U controller has a built-in analog-to-digital conversion module and a logic processing unit.

[0034] The U controller establishes a communication connection with the vehicle's overall controller via the controller area network bus. The overall controller is responsible for the top-level management of the vehicle's power, energy, etc. The high-voltage power supply system (whose power comes from the vehicle's power battery) is controlled by the instructions of the overall controller and can supply power to the water pumps and purification devices in the sewage purification and pipeline system.

[0035] Reference Figure 1 The implementation process of the control method is as follows: When the vehicle leaves the factory or is used for the first time, the system is calibrated. With the clean water tank full of clean water and the waste water tank empty, the reading of the first weighing sensor is recorded as M1 (e.g., 5000 kg), and the reading of the second weighing sensor is recorded as M2 (e.g., 800 kg). M1 and M2 are written into the non-volatile memory of the U controller.

[0036] The vehicle begins its washing and sweeping operation, and the U controller continuously receives real-time weight data W_clean from the first weighing sensor for the clean water tank.

[0037] Scenario A: Wastewater purification and reuse are triggered.

[0038] After a period of operation, the clean water is consumed and W_clean continues to decrease. When the U controller detects that W_clean is below or equal to 0.8M1 (i.e. 4000kg) for 5 consecutive seconds, it determines that the "clean water tank needs to be replenished" state.

[0039] At the same time, the U controller monitors the status of the sewage tank. Assuming that the weight W_dirty transmitted by the second weighing sensor is 1500kg and remains greater than 1.2M2 (960kg) for 5 seconds, and the water level sensor has a signal (indicating that there is liquid level in the tank), the U controller determines that the sewage tank is in a "sewage tank can be purified" state.

[0040] The U controller encapsulates these two status messages into a specific CAN message and sends it to the vehicle controller to request the start of the wastewater purification and reuse process.

[0041] The vehicle controller integrates information such as the vehicle's current driving mode and battery level to determine whether execution is allowed. Subsequently, the vehicle controller sends a start command to the U controller via CAN message and controls the high-voltage power supply system to be turned on.

[0042] After receiving the instruction, the U controller first controls the solenoid valve of the pipeline system to switch to the "purification-reuse" path, and then starts the water pump and purification device. The sewage in the sewage tank is pumped into the purification device, and after multi-stage filtration and purification, the relatively clean water is injected into the clean water tank.

[0043] During this process, the U controller continuously monitors W_clean. When W_clean rises and exceeds 0.8*M1, the system continues to work until W_clean reaches or approaches the calibrated M1 value (e.g., 4900kg). The U controller then considers the clean water tank full and notifies the vehicle controller via a CAN message. The vehicle controller instructs the high-voltage power supply system to cut off power, and the U controller shuts down the water pump and purification device, completing one purification and reuse cycle. This process effectively utilizes the water resources in the wastewater tank and avoids the need to stop and add water midway.

[0044] Situation B: Triggering sewage discharge.

[0045] In another scenario, the cleaning operation is nearing completion, and the clean water tank is still relatively full (W_clean>0.8M1), but the sewage tank has collected a large amount of sewage and garbage, with a weight of up to 2000kg (>1.2M2), and the water level sensor has a signal.

[0046] At this time, the U controller can request the vehicle controller to start the system according to the logic (conditions "1-2" and "2-1" or "2-3" are satisfied at the same time). If permission is granted, the system starts. Since the clean water tank is already full, the injection of purified water will quickly make W_clean reach M1.

[0047] Once the U controller detects that W_clean≥M1, and the wastewater tank is still in the "cleanable" state (the water level sensor still has a signal, indicating that there is still liquid), the U controller will execute the sewage discharge logic. It directly controls the solenoid valve of the pipeline system to switch to the "discharge" path by outputting a signal through a hardwired line (or a specific CAN command).

[0048] Subsequently, the system discharges the remaining liquid in the wastewater tank (which may be the supernatant from the initial separation of wastewater or the rinsing water from the final stage of the purification process) directly outside the vehicle through the drain pipe. The U controller continuously monitors the signal from the water level sensor. When the liquid level in the wastewater tank drops below the sensor detection point, the sensor signal disappears, the U controller determines that the sewage discharge is complete, stops the water pump, and resets the solenoid valve. This function helps to clean the wastewater tank during work breaks or at the end of the operation, prevents sediment from caking, and prepares capacity for the next operation.

[0049] Situation C: System protection and standby.

[0050] If the clean water tank is at a low water level (W_clean≤0.8M1), but the wastewater tank, although heavier (W_dirty≥1.2M2), has no signal from the water level sensor (possibly due to sensor malfunction, or the tank containing extremely dense solids with almost no free liquid), the U controller will generate a "purification prohibited" signal. In this case, even if water needs to be added, the system will not start the purification device to prevent dry pumping from damaging the water pump. The controller can send an alarm to the driver via the instrument panel, prompting them to check the wastewater tank or perform manual intervention.

[0051] In other combinations such as a full clean water tank and an empty wastewater tank, the system remains in standby mode and does not perform any actions.

[0052] Through the closed-loop control described above, the system in this embodiment can intelligently optimize the vehicle status in two dimensions: "water replenishment" and "weight reduction". It prioritizes replenishing clean water by purifying sewage to extend the continuous operation time. When the water replenishment demand is not urgent but the sewage tank is overloaded, it can start sewage discharge in a timely manner to optimize the overall vehicle weight and reduce driving energy consumption. The entire process is highly automated, effectively improving the practicality and economy of the pure electric sweeper.

[0053] Example 2, based on Example 1, further optimizes the control logic to cope with more complex actual road conditions and operational needs.

[0054] The U controller program has added "geofencing" or "operating condition judgment" modules. For example, by using the vehicle's GPS or pre-stored map information, when the vehicle travels to an area with many slopes and high energy consumption, the U controller can work with the vehicle controller to adopt a more aggressive "weight reduction" strategy. Even if the weight of the clean water tank has not yet dropped to 0.8M1, as long as it is slightly lower than M1 (such as 0.9M1) and the wastewater tank meets the "purification" conditions, the system may trigger a small-flow purification and reuse process in advance. The purpose is to transfer the weight of the wastewater tank to the clean water tank as soon as possible (at this time, the total weight of the vehicle remains unchanged, but the maximum weight before subsequent sewage discharge is reduced by consuming some wastewater), or start sewage discharge in advance so that the vehicle enters the high-energy-consumption road section with a lighter weight.

[0055] Conversely, when the vehicle is on a flat road or is about to reach a fixed water replenishment station, the system can adopt a "conservative" strategy, appropriately raising the lower limit of the threshold for triggering water replenishment in the clean water tank (for example, adjusting it to 0.7*M1), so that the clean water tank is used more thoroughly, maximizing the mileage of a single water replenishment operation, while making fuller use of the capacity of the wastewater tank and reducing the number of times wastewater is discharged along the way.

[0056] In addition, the system can also add a learning function. The U controller can record the average rate of fresh water consumption and wastewater generation at different stages of daily operation, and dynamically fine-tune the threshold (such as the coefficient of M1 being 0.8) or determine the delay (such as 5 seconds) accordingly, so that the control is more in line with the actual operating habits of the vehicle and achieves optimal global efficiency.

[0057] Example 3 focuses on illustrating the quantitative analysis of the comprehensive benefits brought by the method of the present invention. It is assumed that a traditional pure electric sweeper needs to be refilled with water 4 times a day, each time taking 30 minutes (including round trip, queuing, and refilling). The daily loss of working time due to refilling water is 2 hours. At the same time, it needs to discharge sewage 3 times a day, each time traveling an average of 5 kilometers with a load to the sewage discharge point (returning empty).

[0058] After applying this invention, the number of times water needs to be added per day can be reduced to twice due to wastewater reuse, saving 1 hour of time. Due to intelligent sewage discharge and weight optimization, the ineffective mileage driven with load can be reduced by about 10 kilometers per day. Based on the vehicle's average energy consumption of 1.5 kWh / km, 15 kWh of electricity can be saved per day. Assuming its battery capacity is 200 kWh, this is equivalent to an increase in driving range of about 10%. At the same time, the effective working time per day increases by 1 hour, and the working efficiency is improved by about 12.5%. In terms of water conservation, based on the daily reuse of 5 tons of wastewater, more than 1,500 tons of clean water can be saved per year, demonstrating significant environmental benefits.

[0059] The above embodiments fully demonstrate the flexibility, intelligence, and significant technical advantages of the method of the present invention. Through the organic combination of hardware system and software logic, the present invention realizes refined and intelligent management of the operation process of pure electric sweeper trucks, solves the long-standing contradiction between efficiency and energy consumption in the industry, and has high promotional value.

[0060] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for controlling the recycling or discharge of wastewater from a new energy pure electric sweeper truck, characterized in that, The sweeper truck includes a clean water tank, a wastewater tank, a wastewater purification device and pipeline system connecting the wastewater tank and the clean water tank, a high-voltage power supply system for powering the purification device, a clean water tank weight sensor, a wastewater tank weight sensor, a wastewater tank water level sensor, a wastewater purification and water transmission controller, and a vehicle controller. The method includes the following steps: S1. Calibrate the initial weight M1 of the clean water tank when it is fully loaded and the initial weight M2 of the waste water tank when it is empty; S2. Based on the data from the clean water tank weight sensor, determine whether the real-time weight of the clean water tank is continuously lower than or equal to the first threshold K1*M1, and generate a clean water tank status signal; where K1 is a coefficient less than 1; S3. Based on the data from the wastewater tank weight sensor and the wastewater tank water level sensor, determine whether the wastewater tank meets the conditions for purification and generate a wastewater tank status signal; S4. The wastewater purification and water transmission controller integrates the status signals of the clean water tank and the wastewater tank, and communicates with the vehicle controller to coordinate the start-up, shutdown and working mode of the high-voltage power supply system and the wastewater purification and pipeline system, so as to perform the operation of purifying and reusing wastewater to the clean water tank or directly discharging it outside the vehicle.

2. The control method for wastewater recycling or discharge from a new energy pure electric sweeper truck according to claim 1, characterized in that, In step S2, the value of K1 in the first threshold K1*M1 ranges from 0.7 to 0.9; the judgment condition is that the real-time weight of the clean water tank is less than or equal to K1*M1 for a continuous first preset time T1, then a low water level trigger signal for the clean water tank is generated. If T1 is continuously greater than K1*M1, a high water level standby signal for the clean water tank is generated.

3. The control method for wastewater recycling or discharge from a new energy pure electric sweeper truck according to claim 1 or 2, characterized in that, Step S3, determining whether the wastewater tank meets the purification conditions, specifically includes: If the real-time weight of the sewage tank is continuously greater than or equal to the second threshold K2*M2 for a second preset time T2, and a water level sensor signal is received, a sewage tank purification trigger signal is generated; where K2 is a coefficient greater than 1. If the real-time weight of the sewage tank is continuously less than K2*M2 for T2, and a water level sensor signal is received, a sewage tank purification trigger signal is generated. If no water level sensor signal is received, a sewage tank purification prohibition signal will be generated regardless of the real-time weight of the sewage tank.

4. The control method for wastewater recycling or discharge from a new energy pure electric sweeper truck according to claim 3, characterized in that, The value of K2 in the second threshold K2*M2 ranges from 1.1 to 1.5; the first preset duration T1 and the second preset duration T2 are both 3 to 10 seconds.

5. The control method for wastewater recycling or discharge from a new energy pure electric sweeper truck according to claim 3, characterized in that, In step S4, the conditions for performing wastewater purification and reuse are: simultaneously receiving a low water level trigger signal from the clean water tank and a purification-ready trigger signal from the wastewater tank; the purification and reuse process continues until the real-time weight of the clean water tank reaches or approaches M1, or the wastewater tank status signal changes to a purification-prohibited signal.

6. The control method for wastewater recycling or discharge from a new energy pure electric sweeper truck according to claim 3, characterized in that, In step S4, the condition for performing sewage discharge is as follows: when the real-time weight of the clean water tank is greater than K1*M1 and reaches or approaches M1, if a sewage tank purification trigger signal is still received, the pipeline system is controlled to switch to discharge mode to discharge the liquid in the sewage tank until the water level sensor signal disappears.

7. The control method for wastewater recycling or discharge from a new energy pure electric sweeper truck according to claim 1, characterized in that, The wastewater purification and water transmission controller communicates with the vehicle controller via a CAN bus; the status signals of the clean water tank, the wastewater tank, and control commands are transmitted in the form of CAN messages.

8. The control method for wastewater recycling or discharge from a new energy pure electric sweeper truck according to claim 1, characterized in that, The method also includes a learning and adaptation step: recording the rate of clean water consumption and the rate of wastewater generation in historical operation data, and dynamically adjusting the values ​​of the coefficients K1, K2 or preset durations T1, T2 based on this.

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