JP2000122734A - Sensor control power converting device for saving power energy - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control a secondary voltage to an arbitrary voltage by increasing or decreasing it to the voltage of about ±20% and to automatically hold a constant voltage and to save electric power by automatically controlling variation in reactance by a semiconductor control element. SOLUTION: A compound transformer T is inserted in series in a line, a control element such as an SCR is connected to the secondary side of the transformer T between both the terminals, and the reactance on the primary side of the transformer T is varied to control the voltage on the load side to an arbitrary voltage. The compound transformer T is inserted in series and the semiconductor control element SCR, etc., increases or decreases the voltage by using reactance variation. Namely, this is a method using the voltage drop across the winding coil through the operation of the reactance and used for voltage adjustment to facilitate fine adjustment. Consequently, no exaggerated structure is needed, so the installation place may be small, automatic control by feedback is performed almost by an electronic circuit, and the lowest illumination is set in unmanned mode to obtain more energy-saving effect, thereby reducing the cost.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a single-phase / three-phase power supply system, and as a part of energy saving measures, increases or decreases the secondary voltage to about ± 20% and controls the voltage to an arbitrary voltage. A device that saves power by maintaining a constant voltage automatically.

[0002]

2. Description of the Related Art Conventionally, a private customer who requires power of 50 kW or more generally negotiates a contract power with a power company and sets a condition for payment of an electric charge (basic fee). An extra charge was charged as a penalty for the excess power usage fee.

[0003] Therefore, each customer has come to install a demand control system as a power monitoring and control measure. However, since it is related to a three-phase power source in addition to a lamp power source, energy saving of a three-phase AC power source for an electric motor is also necessary.

The installation of the demand control system has been divided into the following types. (Ratio control method) When the contracted power is exceeded, the circuit is immediately cut off according to a preset order, and the power is used so as to be less than the contracted power. (Ideal curve method) The power required by the customer is set as an ideal curve, and the power load is adjusted and implemented along the curve. (Predictive control method) According to a change in power demand in a unit time, the last special room is predicted and the increase / decrease of the load is adjusted while comparing with the contract power.

[0005] In addition, when the reactance load is large,
There was a phase lag of the current, the power factor became worse, and wasteful power consumption (reactive power) increased, resulting in lower efficiency. These supplemented the waste of the power factor improvement by using the capacitance together.

In a small-scale device, an electronic circuit based on the electromagnetic theory of resonance uses a resonance circuit of a capacitance and a transformer, and a stable voltage is automatically controlled even when the load fluctuates greatly. Some devices were used.

[0007]

When the power is increased or decreased, a constant voltage cannot be obtained by compensating for the voltage fluctuation due to the fluctuation of the power supply voltage or the load. There was a case where it was desired to change the winding tap of the transformer according to the required voltage. However, the operation was not easy because of the high-voltage equipment.
Even more, in the case of large consumers of electricity, a power outage in the dark would hurt employment. Furthermore, it is impossible at all if it is a transformer tap conversion in a substation facility, and it is desirable to use automatic control.

[0008] Even with the same automatic control, there have recently been devices alleged to be newly developed in the public. However, all of these devices are for cutting off the lighting, and it is impossible to finely adjust the illuminance by the reaction of the human body.

[0009]

[Means for Solving the Problems] It is generally accepted that the voltage adjustment in the substation equipment is performed directly by artificial work by switching with a winding tap (a secondary side voltage adjustment coil tap) attached to a main transformer. Met. However, all these devices
Irregular output voltage control by intermittent contacts by mechanical switches. With this, a stable arbitrary voltage cannot be obtained. In addition, it is not easy to obtain fluctuations in power supply voltage and voltage drop and fluctuation due to load. For this, it is good to insert a single-turn or multiple-turn transformer in series with a line that responds quickly to load fluctuation. There was found. Of course, instead of mechanical control, a semiconductor SCR or an electronic VR variable resistor using a triac or GTO control element is used. In addition, when there are no people, it is not necessary to keep the brightness of the useless illumination. These may be performed by detecting the movement of the human body by a far-infrared sensor or the like and feeding back a control signal.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a circuit configuration and a structure according to the present invention will be described with reference to the drawings. FIG. 1 is a diagram in which an M motor is connected to a general power source, and is operated by operating a SW main switch. FIG. 2 shows that in the case of a general high-power motor load, a large current flows at the time of rotation start, which adversely affects the circuit. Therefore, the switch is started by switching SW2 and SW3 (Y · Δ connection). In addition, as shown in FIG. 4, there are six types of constituent devices in total.

[0011] Other types of voltage control include direct start, star-delta start, reactor start, primary resistance start, condor fan start, and kiza start.

In lieu of these, the apparatus of the present invention shown in FIG. 3 has a very simple structure, and the circuit configuration is shown above. The following table shows the circuit configuration used for a single-phase power supply and a three-phase power supply. .
At the location indicated by T, a single-turn or multiple-turn transformer is inserted in series, and the voltage is increased or decreased by using a reactance change in the semiconductor control element. This principle is a method utilizing a voltage drop generated between both ends of a winding coil by the action of reactance. By using it as the voltage adjustment of the present invention, fine adjustment has been facilitated.

Further, since the electric power in the large-scale substation equipment is increasing, it is impossible to perform an artificial operation, and the operation must be automated. Therefore, in the automatic control by feedback, an arbitrary voltage is detected and set, and the potential is adjusted to the electric potential. The change in reactance is automatically adjusted by the semiconductor control element.

[0014]

According to the present invention, the change in reactance is automatically adjusted by the semiconductor control element, so that there is no need for an exaggerated structure as in the prior art, and the installation place can be small. The automatic control based on feedback is almost entirely performed by an electronic circuit, and when people are unattended, setting the lowest illuminance can further save energy and reduce costs. In addition, there is no failure because it is electronic. Construction costs are low.

[Brief description of drawings]

FIG. 1 is a diagram in which an M motor is connected to a general power supply.

FIG. 2 is a circuit diagram of a Y.Δ starting operation circuit for a general high-power motor load.

FIG. 3 is a circuit diagram of the present invention and a circuit configuration comparison table when used for a single-phase power supply and a three-phase power supply.

FIG. 4 is a comparison table of various conventional motor starting methods.

[Explanation of symbols]

 SW1 Main switch CT Transformer transformer SW2 / SW3 Circuit changeover switch (Y / Δ) M Motor A Ammeter T Compound winding transformer L1 Primary coil L2 Secondary coil TA / TB Coil terminal SCR Rectification control element C Charging capacitor CC Rectifier capacitor VR Variable resistor DA Diac R Resistor L Far infrared sensor

Claims (3)

[Claims] (1) As part of power saving measures, a load voltage is set to ±
In order to increase or decrease the voltage up to about 20%, a multi-turn transformer is inserted in series in the circuit, and a secondary side of the transformer is connected to S
A device for power saving by connecting a CR, or triac or GTO control element between both terminals, changing the reactance on the primary side of the transformer and controlling the voltage on the load side to an arbitrary voltage. 2. An SCR or a triac or GTO control element is connected in parallel with the primary or secondary coil of the transformer in order to change the reactance by inserting a single or multiple winding transformer in series with the power supply circuit. A power saving device characterized in that the voltage on the load side is controlled to an arbitrary voltage to increase or decrease the power on the load side. 3. The power-saving device according to claim 2, wherein the reactance of the transformer is input by a feedback signal using an SCR, a triac or a GTO element, and the automatic lighting control is enabled by a sensor that reacts to a human body. .