Photovoltaic water lifting system

Abstract

The utility model discloses a photovoltaic water lifting system which comprises a photovoltaic array, an inverter module, water pumps and a controller, the inverter module comprises a plurality of photovoltaic water pump inverters which are connected in parallel, each photovoltaic water pump inverter is connected to the photovoltaic array, each photovoltaic water pump inverter is connected with one water pump, and the controller is connected with the water pumps. Each water pump comprises a high-efficiency operation state, a low-efficiency operation state and a stop operation state, the controller is connected with the photovoltaic array and the inverter module, and the controller distributes electric energy to the water pumps by controlling photovoltaic water pump inverters according to the total amount of the electric energy generated by the photovoltaic array. And after the current water pump is in a high-efficiency operation state, the electric energy is distributed to the next water pump. According to the utility model, the total electric energy generated by the photovoltaic array is distributed through the controller, so that part of the water pumps can operate in a high-efficiency operation state, and the rest of the water pumps adaptively operate according to the residual electric energy, thereby improving the water lifting stability of the water lifting system and prolonging the service life of the water pumps.

Description

TECHNICAL FIELD

[0001] The utility model relates to photovoltaic water pumping technical field more particularly, relate to a photovoltaic water pumping system. BACKGROUND

[0002] Photovoltaic water pumping is the radiant energy of the sun is converted into electrical energy, then by electrical energy drive water pump to achieve the effect of pumping water. Solar photovoltaic water pumping system is composed of photovoltaic array, photovoltaic water pump inverter, water pump, photovoltaic array is the radiant energy of solar energy is directly converted into electrical energy device, photovoltaic water pump inverter is the direct current is converted into alternating current to realize inversion, using MPPT to carry out frequency conversion control and maximum power point tracking device for water pump, water pump is the multistage centrifugal pump with wide and efficient working area, is equipped with the water pumping device composed of special solar drive motor.

[0003] As shown in Figure 1 When multiple water pumps are used in parallel, each water pump is connected with a photovoltaic water pump inverter, and is connected to the same photovoltaic array through the photovoltaic water pump inverter connected thereto, since the photovoltaic water pump inverters are independent of each other, each photovoltaic water pump inverter uses its own integrated MPPT function to seize the electrical energy generated by the photovoltaic array in order to enable the water pump connected thereto to output rated power, however, the electrical energy generated by the photovoltaic array due to changes in sunlight conditions cannot satisfy all water pumps to output rated power, causing the water pumps to constantly switch operating states, resulting in unstable water pumping and water pump damage.

[0004] Therefore, a new scheme needs to be proposed to solve the above problems. INVENTION CONTENTS

[0005] The utility model aims at overcoming the deficiency of prior art, and provides a photovoltaic water pumping system.

[0006] In order to achieve the above object, the utility model adopts the following technical scheme:

[0007] A photovoltaic water pumping system, comprising a photovoltaic array, an inverter module, a water pump and a controller, the inverter module comprises a plurality of parallel photovoltaic water pump inverters, each photovoltaic water pump inverter is connected to the photovoltaic array, and each photovoltaic water pump inverter is connected with a water pump, each water pump comprises three states of high-efficiency running state, low-efficiency running state and stop running state, the controller is connected with the photovoltaic array and the inverter module respectively, the controller distributes electrical energy to the water pump by controlling the photovoltaic water pump inverter according to the total amount of electrical energy generated by the photovoltaic array, and makes the current water pump in high-efficiency running state and then distributes electrical energy to the next water pump.

[0008] Further, the controller adjusts the operation state of the water pump corresponding to the photovoltaic water pump inverter by adjusting the output frequency of the photovoltaic water pump inverter.

[0009] Further, the output frequency source of the photovoltaic water pump inverter includes a variable frequency source and a fixed frequency source, the photovoltaic water pump inverter outputs a variable frequency through the variable frequency source to adjust the operation state of the water pump corresponding to the photovoltaic water pump inverter, and the photovoltaic water pump inverter outputs a fixed frequency through the fixed frequency source to make the water pump corresponding to the photovoltaic water pump inverter in a high-efficiency operation state.

[0010] Further, the controller is used for:

[0011] when the water pump is allocated to the electric energy equal to the electric energy required by the rated output power of the water pump, the water pump is controlled to be in a high-efficiency operation state;

[0012] when the water pump is allocated to the electric energy greater than or equal to the electric energy required by the minimum output power of the water pump, and less than the electric energy required by the rated output power of the water pump, the water pump is controlled to be in a low-efficiency operation state;

[0013] when the water pump is allocated to the electric energy less than the electric energy required by the minimum output power of the water pump, the water pump is controlled to be in a stop operation state.

[0014] The beneficial effects of the present application are:

[0015] 1. In the present application, the controller allocates the total amount of electric energy generated by the photovoltaic array, so that part of the water pump can operate in a high-efficiency operation state, and the remaining water pump can operate adaptively according to the remaining amount of electric energy, thereby improving the stability of the water lifting system and prolonging the service life of the water pump.

[0016] 2. In the present application, the output frequency source of the photovoltaic water pump inverter includes a variable frequency source and a fixed frequency source, when the electric energy is sufficient, the photovoltaic water pump inverter outputs the rated frequency of the water pump through the fixed frequency source, so that the water pump is in a high-efficiency operation state; when the electric energy is insufficient, the photovoltaic water pump inverter outputs a variable frequency through the variable frequency source based on the MPPT function, so that the water pump switches between the high-efficiency operation state, the low-efficiency operation state and the stop operation state, thereby improving the stability of the water lifting system. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of a solar photovoltaic water lifting system in the prior art;

[0018] Figure 2 It is a structural schematic diagram of a photovoltaic water lifting system in the present embodiment;

[0019] Figure 3 It is a use schematic diagram of a photovoltaic water lifting system in the present embodiment.

[0020] Reference signs: photovoltaic array 1, inverter module 2, photovoltaic water pump inverter 201, variable frequency source 202, fixed frequency source 203, water pump 3, controller 4. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than 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.

[0022] Embodiment: A photovoltaic water pumping system, as shown in the figure, comprises a photovoltaic array 1, an inverter module 2 and a water pump 3, wherein the photovoltaic array 1 is used to convert the radiant energy of solar energy into electric energy; the inverter module 2 comprises a plurality of parallel photovoltaic water pump inverters 201, each of which is connected to the photovoltaic array 1, and each of which is connected to a water pump 3; the photovoltaic water pump inverter 201 is used to convert direct current into alternating current to realize inversion, integrates the MPPT function, and can use MPPT to perform variable frequency control and maximum power point tracking on the water pump 3; the water pump 3 is a multi-stage centrifugal water pump with a wide and efficient working area, and is equipped with a water pumping device composed of a special solar drive motor. Figure 2

[0023] The output power of the water pump 3 includes rated output power and minimum output power according to the power supply condition, so as to correspond to three states of high-efficiency running state, low-efficiency running state and stop running state of the water pump 3, and specifically:

[0024] When the electric energy allocated to the water pump 3 is equal to the electric energy required by the rated output power of the water pump 3, the power output by the water pump 3 is the rated output power, and the water pump 3 is in the high-efficiency running state;

[0025] When the electric energy allocated to the water pump 3 is less than the electric energy required by the minimum output power of the water pump 3, the water pump 3 stops running and is in the stop running state;

[0026] When the electric energy allocated to the water pump 3 is greater than or equal to the electric energy required by the minimum output power of the water pump 3 and less than the electric energy required by the rated output power of the water pump 3, the power output by the water pump 3 is greater than or equal to the minimum output power and less than the rated output power, and the water pump 3 is in the low-efficiency running state.

[0027] ​The photovoltaic water pumping system further comprises a controller 4 connected with the photovoltaic array 1 and the inverter module 2 respectively, the controller 4 distributes the electric energy generated by the photovoltaic array 1 to the water pumps 3 through controlling the photovoltaic water pump inverters 201, and the current water pump 3 is in the high-efficiency running state before the electric energy is distributed to the next water pump 3.

[0028] Specifically, in use, the controller 4 first distributes the electric energy required by the rated output power of the current water pump 3 to the current water pump 3 through the current photovoltaic water pump inverter 201, so that the current water pump 3 is in the high-efficiency running state, and then distributes the electric energy to the next water pump 3 through the next photovoltaic water pump inverter 201.

[0029] When the electric energy distributed to the next water pump 3 can meet the electric energy required by the rated output power of the next water pump 3, the next water pump 3 is in the high-efficiency running state, and then the electric energy is distributed to the next water pump 3 through the next photovoltaic water pump inverter 201.

[0030] When the electric energy distributed to the next water pump 3 is greater than or equal to the electric energy required by the minimum output power of the next water pump 3 and less than the electric energy required by the rated output power of the next water pump 3, the next water pump 3 is in the low-efficiency running state, and at the same time, the next photovoltaic water pump inverter 201 uses the MPPT function to track the maximum power point of the photovoltaic array 1, and if the electric energy distributed to the next water pump 3 is increased to the electric energy required by the rated output power of the next water pump 3, the next water pump 3 switches to the high-efficiency running state.

[0031] When the electric energy distributed to the next water pump 3 is less than the electric energy required by the minimum output power of the next water pump 3, the next water pump 3 is in the stop running state, and at the same time, the next photovoltaic water pump inverter 201 uses the MPPT function to track the maximum power point of the photovoltaic array 1, and if the electric energy distributed to the next water pump 3 is increased to the electric energy required by the minimum output power of the next water pump 3 and less than the electric energy required by the rated output power of the next water pump 3, the next water pump 3 switches to the low-efficiency running state.

[0032] Further, the controller 4 adjusts the running state of the water pump 3 corresponding to the photovoltaic water pump inverter 201 by adjusting the output frequency of the photovoltaic water pump inverter 201.

[0033] The output frequency source of the photovoltaic water pump inverter 201 includes a variable frequency source 202 and a fixed frequency source 203, the photovoltaic water pump inverter 201 outputs a variable frequency through the variable frequency source 202 to adjust the running state of the water pump 3 corresponding to the photovoltaic water pump inverter 201, and the photovoltaic water pump inverter 201 outputs a fixed frequency through the fixed frequency source 203 to make the water pump 3 corresponding to the photovoltaic water pump inverter 201 in the high-efficiency running state.

[0034] Specifically, the controller 4 controls the photovoltaic water pump inverter 201 to make the photovoltaic water pump inverter 201 output the rated frequency of the water pump 3 through the fixed frequency source 203, so that the water pump 3 is in a high-efficiency running state; the controller 4 controls the photovoltaic water pump inverter 201 to make the photovoltaic water pump inverter 201 output a variable frequency through the variable frequency source 202 based on the MPPT function, so that the water pump 3 switches between the high-efficiency running state, the low-efficiency running state and the stop running state.

[0035] As shown in Figure 3 When the three water pumps 3 (water pump A, water pump B and water pump C) are used in parallel, each water pump 3 is connected with a photovoltaic water pump inverter 201 (photovoltaic water pump inverter A, photovoltaic water pump inverter B and photovoltaic water pump inverter C) and is connected to the same photovoltaic array 1 through the photovoltaic water pump inverter 201 connected thereto; wherein the rated output power of the photovoltaic water pump inverter A, the photovoltaic water pump inverter B and the photovoltaic water pump inverter C is 50 kW, the minimum output power is 30 kW, and the rated frequency is 50 Hz.

[0036] When the total amount of electric energy generated by the photovoltaic array 1 is 85 kW, the controller 4 controls the photovoltaic water pump inverter A, the photovoltaic water pump inverter A outputs the rated frequency 50 Hz through the fixed frequency source 203, so that the water pump A is in a high-efficiency running state and outputs the rated output power; after the electric energy of the water pump A is distributed, the total amount of electric energy generated by the photovoltaic array 1 is still 35 kW, which is not enough for the water pump B to output the rated output power, at this time, the controller 4 controls the photovoltaic water pump inverter B, the photovoltaic water pump inverter B outputs a variable frequency through the variable frequency source 202, so that the water pump B is in a low-efficiency running state, and the photovoltaic water pump inverter B performs maximum power point tracking on the photovoltaic array 1 based on the MPPT power; when the total amount of electric energy generated by the photovoltaic array 1 increases and can meet the electric energy required by the rated output power of the water pump B, the water pump B switches to a high-efficiency running state; after the electric energy of the water pump A and the water pump B is distributed, there is no electric energy left to distribute to the water pump C, and the water pump C is in a stop running state.

[0037] When the total amount of the electric energy generated by the photovoltaic array 1 is 75kW, the controller 4 controls the photovoltaic water pump inverter A to output the rated frequency 50Hz through the fixed frequency source 203, so that the water pump A is in the high efficiency operation state and outputs the rated output power; after the power distribution of the water pump A, the total amount of the electric energy generated by the photovoltaic array 1 is 25kW, which is not enough for the water pump B to output the minimum output power, so the water pump B is in the stop operation state; at the same time, the photovoltaic water pump inverter B tracks the maximum power point of the photovoltaic array 1 based on the MPPT power; when the total amount of the electric energy generated by the photovoltaic array 1 increases and can meet the electric energy required by the minimum output power of the water pump B, the water pump B switches to the low efficiency operation state; and the water pump C cannot be distributed with the electric energy because there is no electric energy left, so the water pump C is in the stop operation state.

[0038] The preferred embodiments of the present application have been described above, the protection scope of the present application is not limited to the above-mentioned embodiments, any technical scheme falling within the idea of the present application belongs to the protection scope of the present application. It should be noted that, for the ordinary skilled in the art, some improvements and decorations without departing from the principle of the present application are also considered as the protection scope of the present application.

Claims

1. A photovoltaic water lifting system, comprising a photovoltaic array (1), an inverter module (2), a water pump (3), and a controller (4), characterized in that, The inverter module (2) includes multiple photovoltaic water pump inverters (201) connected in parallel. Each photovoltaic water pump inverter (201) is connected to the photovoltaic array (1), and each photovoltaic water pump inverter (201) is connected to a water pump (3). Each water pump (3) has three states: high-efficiency operation, low-efficiency operation, and stop operation. The controller (4) is connected to the photovoltaic array (1) and the inverter module (2) respectively. The controller (4) distributes electrical energy to the water pump (3) by controlling the photovoltaic water pump inverter (201) according to the total amount of electrical energy generated by the photovoltaic array (1), and distributes electrical energy to the next water pump (3) after the current water pump (3) is in a high-efficiency operation state.

2. The photovoltaic water lifting system according to claim 1, characterized in that, The controller (4) adjusts the operating state of the water pump (3) corresponding to the photovoltaic water pump inverter (201) by adjusting the output frequency of the photovoltaic water pump inverter (201).

3. The photovoltaic water lifting system according to claim 2, characterized in that, The output frequency source of the photovoltaic water pump inverter (201) includes a variable frequency source (202) and a fixed frequency source (203). The photovoltaic water pump inverter (201) outputs a variable frequency through the variable frequency source (202) to adjust the operating state of the water pump (3) corresponding to the photovoltaic water pump inverter (201). The photovoltaic water pump inverter (201) outputs a fixed frequency through the fixed frequency source (203) to make the water pump (3) corresponding to the photovoltaic water pump inverter (201) operate in a high-efficiency state.

4. The photovoltaic water lifting system according to claim 1, characterized in that, The controller (4) is used for: When the electrical energy allocated to the water pump (3) is equal to the electrical energy required for the rated output power of the water pump (3), the water pump (3) is controlled to operate in a high-efficiency state; When the electrical energy allocated to the water pump (3) is greater than or equal to the electrical energy required for the minimum output power of the water pump (3) and less than the electrical energy required for the rated output power of the water pump (3), the water pump (3) is controlled to be in a low-efficiency operating state. When the electrical energy allocated to the water pump (3) is less than the electrical energy required for the minimum output power of the water pump (3), the water pump (3) is controlled to be in a stopped state.

Images