TWM498315U - Motor device with simplified power measurement - Google Patents

Description

Motor device capable of simplifying power measurement

This creation relates to motor devices, and more particularly to a motor device that simplifies power measurement.

Due to the extreme climate, all countries in the world have vigorously promoted energy conservation and carbon reduction. At present, the international standard ISO50001 energy management standard is actively promoting. Among them, electric energy monitoring and recording is an important management project. However, due to the high cost of power management monitoring system construction, Therefore, it was hindered when the factory was implemented. Therefore, if the cost of the electric energy measuring device can be effectively reduced, it will help to promote the power management of the factory, thereby achieving the purpose of saving electricity.

Moreover, in a general factory, a three-phase motor is a common power device, and in power planning, a separate motor drive power is generally supplied to a three-phase motor by a MCC-motor control center. A motor protection device is disposed in the motor control center. Since the motor control center can supply power to a plurality of three-phase motors, to monitor the power consumption of each three-phase motor, a three-phase is added to the connection circuit between the motor control center and each three-phase motor. The electric meter and three CT (current transformer) have high construction cost, which is what needs to be improved.

In order to solve the aforementioned problems, there is a need for a motor device that simplifies power measurement.

One of the aims of the present invention is to disclose a motor device that simplifies power measurement by simplifying the power measurement procedure of a three-phase motor by a pre-established comparison table of power factor and phase current.

Another object of the present invention is to disclose a motor device that simplifies power measurement, which can estimate the three-phase power of the three-phase motor by measuring only one phase current during operation of a three-phase motor.

In order to achieve the above object, a motor device capable of simplifying power measurement is proposed, which has: a three-phase motor; an ammeter coupled to a phase power line of the three-phase motor to obtain a phase current measurement And a power calculation unit having at least one memory for storing a nominal phase voltage value and a power factor and phase current comparison table, wherein the power calculation unit is based on the phase current measurement value from the power The comparison table of the factor and the phase current obtains a power factor, and a three-phase power is obtained according to the phase current measurement value, the rated phase voltage value, and the power factor multiplied by three times.

In one embodiment, the nominal phase voltage value is a pre-input value.

In an embodiment, the ammeter comprises a current comparator.

In one embodiment, the three phase motor is powered by a motor control center.

In order to provide a further understanding of the structure, features, and objects of the present invention, the detailed description of the drawings and the preferred embodiments are set forth below.

100‧‧‧Three-phase motor

110‧‧‧ galvanometer

120‧‧‧Power calculation unit

200‧‧‧Motor Control Center

Figure 1 depicts a typical motor power factor table.

2 is a block diagram of a preferred embodiment of a motor device that simplifies power measurement.

The principle of this creation will be explained first. According to IEEE Std1459-2000, under the condition that the three-phase is balanced and the voltage is sinusoidal, the three-phase power can be equivalent to 3* phase voltage*phase current*power factor. In the three-phase motor system of the direct drive of the mains, since the motor drive power supply and the three-phase motor are all three-phase balanced, and the power supply is a three-phase balanced sine wave, the three-phase power of the three-phase motor can be calculated according to the above formula. .

In addition, please refer to FIG. 1, which shows a typical motor power factor table. As can be seen from Figure 1, a motor will have different power factors under different load conditions. Moreover, in the general case, the mains voltage can be regarded as a fixed constant. Therefore, when the voltage is fixed, there is a correspondence between the current and the power factor of the motor.

According to the above description, the creation is a comparison table between the phase current and the power factor of a three-phase motor under a nominal phase voltage value. In operation, the creation only measures the single-phase current, and after obtaining a single-phase current value, obtains the power factor value corresponding to the single-phase current value from the comparison table, and then according to the rated phase voltage value, The single-phase current value, the power factor value, and the power calculation formula estimate the three-phase power of the three-phase motor.

Referring to FIG. 2, a block diagram of a preferred embodiment of the motor device for simplifying power measurement is illustrated. As shown in FIG. 2, the motor device for simplifying power measurement includes a three-phase motor 100, an ammeter 110, a power calculation unit 120, and a motor control center 200.

Three-phase motor 200 by a supply line 100 the motor control center, and the three-phase power _V ψ1, V ψ2, and _V ψ3 based presentation and pairwise disjoint equilibrium phase angle difference of 120 degrees.

The galvanometer 110 is coupled to a phase power line of the three-phase motor 100 to obtain a phase current measurement value I _{ψ 1} . The galvanometer 110 can include a current transformer to measure a large current.

The power calculation unit 120 has at least one memory (not shown) for storing a rated phase voltage value and a power factor and phase current comparison table, wherein the power calculation unit is based on the phase current measurement value I _{ψ 1} A power factor is obtained from the comparison table of the power factor and the phase current, and a three-phase power is obtained by three times the product of the phase current measurement value I _{ψ 1} , the rated phase voltage value, and the power factor.

Since the phase voltage of the three-phase motor 100 can be regarded as fixed during actual operation, we can input a nominal phase voltage value, for example 380 (V), without having to measure it during actual operation.

According to the above technical solutions, this creation can provide the following effects:

1. The motor device for simplifying power measurement of the present invention can simplify the power measurement procedure of a three-phase motor by a pre-established comparison table of power factor and phase current.

2. The motor device capable of simplifying the power measurement of the present invention only needs to measure one phase current during the operation of a three-phase motor to estimate the three-phase power of the three-phase motor, thereby greatly saving the three The measurement cost of the phase motor device.

The disclosure of the present invention is a preferred embodiment. Any change or modification of the present invention originating from the technical idea of the present invention and being easily inferred by those skilled in the art will not deviate from the scope of patent rights of the present invention.

In summary, the case, regardless of its purpose, means and efficacy, is showing its technical characteristics that are different from the conventional ones, and its first creation is practical, and it is also in compliance with the new patent requirements. Pray for the patents at an early date.

100‧‧‧Three-phase motor

110‧‧‧ galvanometer

120‧‧‧Power calculation unit

200‧‧‧Motor Control Center

Claims (4)

A motor device capable of simplifying power measurement, comprising: a three-phase motor; an galvanometer coupled to a phase power line of the three-phase motor to obtain a phase current measurement value; and a power calculation unit, a comparison table having at least one memory for storing a nominal phase voltage value and a power factor and a phase current, wherein the power calculation unit is obtained from the comparison table of the power factor and the phase current according to the phase current measurement value A power factor, and a three-phase power is obtained by three times the product of the phase current measurement value, the rated phase voltage value, and the power factor. A motor device for simplifying power measurement as described in claim 1, wherein the rated phase voltage value is a pre-entered value. A motor device as claimed in claim 1, wherein the galvanometer comprises a current comparator. A motor device for simplifying power measurement as described in claim 1, wherein the three-phase motor is powered by a motor control center.