JPH04344173A - Reactor protective device - Google Patents

Abstract

PURPOSE:To prevent the burning of a reactor caused by the thermal runaway of the reactor which takes place when the current to the reactor increases or the ambient temperature rises by detecting the temperature of the reactor. CONSTITUTION:This reactor protective device is constituted in such a way that a rectifier 102 which is connected with a reactor 103 is connected to commercial power supply 101 and a temperature detecting sensor 1 is fitted to the reactor 103. In addition, a motor 107 is connected to an eletrolytic capacitor 104 and power transistor 105 as a load and a control section 106 which controls an electric current and fetches the signal of the sensor 1 is also connected to the capacitor 104 and transistor 104. Since the temperature sensor 1 limits the electric current flowing to the transistor 105, the electric current and heat generation of the reactor 103 can be suppressed and the reactor 103 can be protected.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protection device for a reactor of equipment such as an air conditioner having a rectifier circuit and through which a large current flows.

0002

2. Description of the Related Art In recent years, in direct current conversion circuits using this type of rectifier, failures due to heat generation have been increasing in devices that flow large currents, such as air conditioners. In particular, the heat generated by the reactor has a very large effect, and it is necessary to suppress the temperature of this reactor. Conventionally, such protection devices were not provided and the reactor was cooled only by ventilation air.When evaluating a reactor, the environmental conditions were set and the temperature of the reactor met the specified value under the conditions when the maximum load was applied. It was common to design. The configuration will be described below with reference to FIG. 2.

As shown in the figure, a rectifier 102 connected to a commercial power source 101, a reactor 103 connected to this rectifier 102, an electrolytic capacitor 104 and a power transistor 105 connected to this reactor 103.
, an electric motor 107 connected to this power transistor 105 , and a control section 106 that controls the power transistor 105 .

0004

[Problems to be Solved by the Invention] In such a conventional configuration, even if the temperature of the reactor 103 rises when the outside temperature rises or when the current is increased to increase the capacity, there is no means to lower the temperature, resulting in thermal runaway. In the worst case, the reactor 103 would be burnt out.

[0005] The present invention solves the above problems by providing a device that protects the reactor by attaching a temperature sensor to the reactor and suppressing the current flowing through the reactor based on the signal from the temperature sensor to lower the temperature of the reactor. is intended to provide.

[0006]

[Means for Solving the Problems] In order to achieve the above object, the present invention connects a rectifier to a commercial power source, and includes a reactor for improving the power factor connected to one side of the rectifier;
A smoothing electrolytic capacitor and a power transistor are connected to this reactor, the electrolytic capacitor and the power transistor are connected to the other side of the rectifier, and the power transistor is connected to a control unit that controls a motor and the power transistor. Furthermore, the reactor is equipped with a temperature sensor that detects the temperature of the reactor itself, and this temperature sensor is connected to the control unit, and a reactor protection device is provided by suppressing heat generation in the reactor based on a signal from the temperature sensor. It is composed of

[0007]

[Operation] With the above configuration, the control section receives a signal from the temperature sensor attached to the reactor, and this control section outputs a signal for controlling the current flowing through the power transistor, thereby controlling the current flowing through the power transistor. can be controlled and the current flowing through the reactor can be controlled.

[0008]

[Embodiment] An embodiment of the present invention will be described below with reference to FIG. Note that the same reference numerals as those used in the conventional example indicate the same components, and a description thereof will be omitted. That is, in FIG.
A rectifier 102 is connected to a commercial power source 101, a reactor 103 is connected to the rectifier 102, a temperature sensor 1 is attached to the reactor 103 to detect the temperature of the reactor 103, and an electrolytic capacitor 104 and a power transistor 105 are connected. One of the electrolytic capacitor 104 and the power transistor 105 is connected to the rectifier 102, and the power transistor 105 is connected to a control unit 106 that controls the current flowing through the power transistor 105, and a motor 1 as a load.
07 is connected, and the control unit 106 receives the signal from the temperature sensor 1.

With the above configuration, when a larger load is applied to the motor 107, a larger current flows through the motor 107. At this time, the current in the reactor 103 also increases and the temperature thereof increases. Before the temperature of the reactor 103 at that time becomes abnormal, the control section 107 controls the power transistor 105.
A control signal is output in the direction of reducing the current to reduce the current flowing to the motor 107, thereby reducing the current flowing to the reactor 103, thereby making it possible to lower the temperature.

0010

Effects of the Invention As is clear from the above embodiments, according to the present invention, a temperature sensor is provided in the reactor to detect the temperature of the reactor and control the current flowing through the reactor. It is possible to provide a reactor protection device that can prevent burnout due to thermal runaway in the reactor main body, and can also alleviate the adverse effects on other electronic components caused by the heat.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of a reactor protection device showing an embodiment of the present invention.

[Figure 2] Configuration diagram of a conventional reactor without protection function

[Explanation of symbols]

1 Temperature sensor 101 Commercial power supply 102 Rectifier 103 Reactor 104 Electrolytic capacitor 105 Power transistor 106 Control section 107 Electric motor

Claims (1)

[Claims] Claim 1: A rectifier is connected to a commercial power supply, a reactor for improving the power factor is connected to one side of the rectifier, a smoothing electrolytic capacitor and a power transistor are connected to the reactor, and a smoothing electrolytic capacitor and a power transistor are connected to the reactor. A power transistor is connected to the other side of the rectifier, and a control unit that controls an electric motor and the power transistor is connected to the power transistor, and the reactor further includes a temperature sensor that detects the temperature of the reactor itself, This temperature sensor is connected to the control section, and the reactor protector is configured to suppress heat generation in the reactor based on a signal from the temperature sensor.