What is the reason why air conditioning consumes a lot of power?

1. The impact of energy consumption level on the use of electrical appliances

When we buy an air conditioner, if we want to judge the cooling capacity of an air conditioner, the best way is to look at its output power.

Under ideal conditions, the output power of 1 horsepower is about 2400 watts. The energy efficiency ratio of air conditioners = air conditioner output power / air conditioner input power. Therefore, according to the formula, we can know that under the same cooling effect, the higher the energy efficiency ratio, the lower the power consumption. As shown in Figure 1, the three-level energy efficiency standard set by the new national energy consumption standard for air conditioners.

Figure 1 New energy efficiency standards

Therefore, if you find that the cooling effect of your air conditioner is average but the power consumption is very high, it is very likely that the energy efficiency level of the air conditioner is low, resulting in excessive energy consumption.

2. The significance of more advanced energy consumption levels

With the rapid economic growth of various countries, the demand and ownership of household appliances have increased dramatically, and such growth has brought huge energy consumption and caused serious pollution to the environment. As shown in Figure 2, in order to reduce the pollution of these household appliances to the environment, countries around the world have formulated and implemented energy efficiency standards and promoted energy efficiency labeling systems to improve the energy efficiency of energy-using products, promote energy-saving technology progress, and thus reduce harmful emissions and protect the environment.

Figure 2 Energy efficiency label

3. Power meter energy consumption test solution for household appliances

More and more home appliances are using frequency conversion technology, which saves energy but also distorts the waveform signal of the product. In addition, due to the application of frequency conversion, the working state of home appliances is frequently changed during operation, resulting in a wide range of changes in the working current, which can drop from tens of amperes to a few milliamperes. So, what kind of instrument can meet the test and measurement requirements for frequency conversion home appliances such as air conditioners?

Figure 3: Test diagram of household and office appliances

As shown in Figure 3, this is a test diagram of household and office appliances. Here we take air conditioners as an example to share with you the difficulties in testing variable-frequency household appliances.

Difficulty of testing

1. While frequency conversion appliances save energy, they also cause the waveform signals of the products to be easily distorted. These distorted waveforms are all non-sinusoidal signals, such as pulse waves, triangle waves, rectangular waves, trapezoidal waves and pulse waves, etc., which contain abundant high-frequency harmonic components. Ordinary power meters cannot accurately measure high-frequency components due to sampling rate and bandwidth limitations, so there is a huge gap between their measured values ​​and the actual values.

2. General power measuring instruments only allow power measurement within the same range in integration mode, which cannot meet the requirements for correct power measurement of variable-frequency household appliances.

Solution

Figure 4 Relationship between frequency conversion household appliance signal and power meter bandwidth

As shown in Figure 4, we can see that with a low-bandwidth power meter, the high-frequency components in the signal are filtered out by the analog front-end circuit, resulting in energy loss. The 300KHz bandwidth of the ZHIYUAN Electronics power meter fully meets the power consumption measurement requirements of new technology products such as variable-frequency home appliances.

Figure 5 Comparison of fixed range and automatic switching range

The PA300 series digital power meter adopts a new design architecture and has made multiple optimizations in low power consumption measurement. It has higher power factor accuracy and is very suitable for standby power consumption measurement. In addition, the harmonic analysis function up to 50th order allows you to analyze the waveform quality more accurately. As shown in Figure 5, the automatic range switching function of this series of power meters in the integration mode provides a guarantee for the accurate measurement of variable frequency household appliances power.

Summarize

The PA300 series digital power meter has a maximum sampling rate of 500KS/s, a bandwidth of 300KHz, and can automatically switch the range in the integration mode for variable-frequency home appliances. It also supports wide current input and other features, providing a reliable power measurement solution for the test of working power consumption.