At the time of the initial frequency of the motor is fixed in our country, the output of the motor can only be fixed a power plant protection unmanned aerial vehicle (uav) power system, a voltage. So the time of the motor at the time of work output of the driving frequency is completely the same. But often needed to load the driving frequency is changing, in order to be able to meet the needs of the load driving frequency, driving frequencies are generally greater than the load rating of the motor driven frequency you need. Although doing so can provide enough of motor drive frequency, ensure the normal operation of the motor, but there are a large part of the driving frequency will be wasted, and this creates a lot of electric energy is wasted and cannot be effectively used, do not conform to the requirements of the strategy for the sustainable development of our country completely.
in order to save electricity, make full use of the electric power demand, motor frequency conversion control technology is developed, motor frequency conversion control can according to the load required to drive frequency to change the motor output power and voltage, ensure that there won't be redundant drive is wasted, improved energy utilization ratio, good completely accord with the requirement of energy conservation and emissions reduction in China. Along with our country more and more high to the requirement of energy conservation and emissions reduction, for the development and research of the control system of variable frequency energy saving also constantly improve, and get a better promotion, has been applied in more and more places.
the development and application of motor frequency conversion control analysis
1. The development of the motor frequency conversion technology
now the motor variable frequency system is mostly used in constant V/F control system, the characteristics of the frequency conversion control system is of simple structure, cheap fabrication. This system is widely used in fan and other large and dynamic performance requirements for frequency conversion system is not very high. This system is a kind of typical open-loop control system, this system can satisfy most if smooth with the variable speed motor, plant protection unmanned aerial vehicle (uav) power system, but for the adjustment of the dynamic and static performance is limited, and cannot be applied in the dynamic and static performance requirements more stringent.
in order to achieve high performance and the static and dynamic adjustment, we can only be used to implement the closed-loop control system. So some researchers put forward the closed-loop slip frequency control of motor speed control mode, this way of speed adjustment to achieve high performance in static and dynamic speed, but the system only has been applied in motor speed is slow, because when the speed of the motor is higher, the system will not achieve the purpose of saving electricity, also can make the motor transient current greatly, makes the motor torque change in an instant. So in order to achieve at a high speed in the high dynamic and static performance, only to solve the problem of motor produce transient current, only reasonable solution to the question we can better the development of the motor frequency conversion energy-saving control technology.
2. Motor frequency conversion control application
in the energy consumption of the motor, about seventy percent are applied in the middle of the fan and pump load, so the motor frequency conversion control technology is good for saving energy consumption of this part of the load, achieve the goal of energy conservation and emissions reduction. Air conditioning to illustrate it, there is no application of frequency conversion air conditioning control system, at the time of setting temperature is lower than the threshold, can shut down the wind road ways to do this, but this time the motor of air conditioning in the work, this part of driving power is not being used, simply wasted. But in won the frequency conversion control system of air conditioning, if when the temperature of the air conditioning set lower, only need to control the speed of the motor is reduced, to reduce the driving power of the output can be achieved, no need to will be shut down the wind road, but also won't waste motor driven frequency, good improves the utilization efficiency of electric power.
