Online learning optimization design method for photovoltaic water pump system rotation speed adjustor

Abstract

The invention discloses an online learning optimization design method for a photovoltaic water pump system rotation speed adjustor. The method has the beneficial effects that on the basis of a vector control mode of a position sensorless, an outer ring control strategy with a rotation speed amplitude limiting ring and a DC voltage ring in parallel is adopted, when the maximal output power of an array is larger than rated pump power, the rotation speed amplitude limiting ring works, the rotation speed of the motor is stabilized at a rated rotation speed, the motor can thus be ensured not to exceed the speed, and safety and reliability of the system are improved; a simple VF open ring control mode is adopted for measuring torque of a water pump load, the rotation speed of the water pump is changed through changing the given frequency so as to calculate a load torque corresponding to each rotation speed, and the water pump load features are drawn in a secondary curve mode; rotational inertia of the system is measured in an online mode in a load state, no-load operation of the water pump is not needed, the rotational inertia can be conveniently measured even in the load condition, a mode of calculating a mean value through multiple times of measurement is adopted, the measurement result is more accurate.

Description

technical field [0001] The invention relates to an online learning optimization design method for a speed regulator of a photovoltaic water pump system, and belongs to the technical field of photovoltaic water pump inverters. Background technique [0002] Photovoltaic water pump inverters use the energy of photovoltaic arrays to drive photovoltaic water pumps to extract water from deep wells, rivers, rivers, lakes, ponds and other water sources. The speed of the water pump in the photovoltaic water pump system must be limited below the rated speed to ensure that the water pump and the motor will not be overloaded. When the maximum output power of the photovoltaic array is greater than the rated power of the water pump motor, the inverter of the water pump motor must enter the power limiting state to limit the power of the motor to run at the rated power. Generally, there are three methods: 1) Frequency limiting, which can be used for In the VVVF stabilized voltage working m...

AI Technical Summary

Problems solved by technology

However, the array voltage stability of this method is poor, and the parameters of the voltage regulator are difficult to optimize

2) Torque current limitation, because the load torque of the water pump is proportional to the square of the speed, limiting the torque current limits the speed

How to obtain the load torque value under load is very important. The load torque of the water pump is proportional to the square of the speed. It is difficult to accurately estimate it with general measurement methods. The existing methods for identifying the moment of inertia under load mainly use parameter adaptive algorithms. To solve the problem, there is no need to measure the load torque, but the calculation is complex and requires high control performance of the system

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