JPH0318277A - Inverter device - Google Patents

Abstract

PURPOSE:To prevent switching elements from being turned ON simultaneously by external noise, etc., by providing a drive blocking means to block the drive of switching elements caused by the output of a dependent control circuit by a stop signal in an inverter device where there is a relationship of master and subsidiary among components. CONSTITUTION:Suppose a stop signal V3 is outputted from a stop signal output circuit 3, the stop signal V3 is inputted into an oscillation circuit 5 and the oscillating action is stopped. At this time both output signals VA and VB will be on a low level. At the same time, the stop signal V3 is inputted into a photocoupler PC, the phototransistor of which will thereby be turned ON. Further, by discharging the charged electric charge carrier at a capacitor C1, the DC power supply E2 from a charging circuit 81 to a control circuit 11 is stopped.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention has a master-slave relationship between control circuits that drive switching elements on and off, respectively, and the operation can be started by inputting a stop signal to the main control circuit. Stop? This invention relates to an inverter device.

[Jubei Technique 1 FIG. 6 shows an inverter device of this type manufactured by Jumei.

This inverter device has switching elements Q, Q2 connected in series to both ends of a DC power source E, each switching element Q, Q2 being individually driven by a control circuit 112, and connected in parallel to switching element Q2. AC power switched by a switching element QI, 0.2 is supplied to the load circuit 2.

The DC power source E may be a battery or a DC power source obtained by rectifying and smoothing an AC power source (commercial power source). Further, as the switching element QyQ2, a power MOS transistor, a bibolar transistor, a relay, or the like is used.

The load circuit 2 may be connected in parallel to the switching element Q, and when this inverter device is used as a discharge lamp lighting device, the load circuit 2 connects, for example, a discharge lamp as a load and a L. It is composed of a C resonant circuit.

Further, each control circuit 11, 1■ operates using an individually provided DC power source E2, E as a power source. These controls? Road 1 ■
, 12 have a master-slave relationship, and in this inverter device, control circuit 1■ is the "master" and the other control circuit II is the "slave".
It has become. The output V of each of these control circuits 112
+tVzhaM 7 [1i1] (a), (IJ) J. =
As shown in t, high and low levels are alternately repeated, and the control circuit 12 becomes high level when the output V2 of the main control circuit 12 switches from high level to low level. Note that this output V,,
A dead-off period TI3 is provided in which both switching elements Q.V2 and Q.V2 are at low level. , Q2 are both turned on to prevent a power supply short-circuit condition. By the way, some of these types of inverter devices are capable of remotely controlling the stop of their operation, and such inverter devices can be controlled remotely.
When related control circuits i, , i2 are used, the operation of the control circuit 11 can also be stopped by simply inputting a stop signal as a far I control signal to the main control circuit 12.

[Problem to be solved by the invention 1 By the way, a control circuit with such a master-slave relationship 1■12
Is your inverter device stopped? In this case, if foreign noise or the like is superimposed on the main control circuit 12 and the control circuit 12 operates, the control circuit 11 also operates accordingly. At this time, normal outputs V, , V2 are not output from the control II1 circuit 1■12, and the switching elements Q,
, Q2 may be turned on simultaneously.

The present invention has been made in view of the above-mentioned points, and its purpose is to provide an inverter 81=Wt that prevents switching elements from being turned on simultaneously due to foreign noise or the like.

Means for Solving 1 Problem] In order to achieve the above object, the present invention includes a drive blocking means for blocking the driving of the switching element by the output of the dependent control circuit using a stop signal.

"Function 1" As described above, the present invention is provided with a drive blocking means for blocking the driving of the switching element by the output of the dependent control circuit in response to the stop signal, so that the operation of the inverter device is stopped by the stop signal. Even if foreign noise or the like is superimposed on the control circuit, the corresponding switching element is not turned on from the dependent control circuit, thereby preventing the occurrence of a power supply short-circuit condition due to simultaneous turning on of the switching elements.

[Example 11 An embodiment of the present invention is shown in FIGS. 1 to 3.

Inperter of this example! ! The location is as shown in Figure 1.
A drive blocking means 4 such as a switch is provided in the power supply line of the control circuit 11, so that when the stop signal V3 is input to the control circuit 12, the stop signal V3' causes the control circuits 1,
This is to stop the supply of DC power E2 to. Here, the stop signals V3, V3' are generated by the stop signal output circuit 3, and the stop signals v, , v3' are the same, but the routes to which they are supplied are different, so they are differentiated as described above. .

In the following explanation, the stop signal will be unified to V3.

Figure 2 shows a concrete circuit. In this embodiment, the control circuit 12 is connected to a switching element Q. , Q2 is turned on alternately, 4? 7 and an oscillation circuit 5 that outputs a signal to
A drive circuit 62 turns on and off the switching element Q2 based on the output of the oscillation circuit 5, and a Karen mirror circuit 72 receives an inverted output from the output supplied to the drive circuit 62 of the oscillation circuit 5. It has been done. Incidentally, this control circuit 12 is supplied with a DC power source E3 from a charging circuit 82 consisting of a resistor R2 and a capacitor C2. On the other hand, control circuit 1. are a current mirror circuit 71 to which the output of the current mirror circuit 72 of the control circuit 1■ is input, and this current mirror circuit 7. A drive circuit 6 turns on and off the switching element Q2 based on the output of the control circuit 1, and a DC power supply E2 is supplied to the control circuit 1 from a charging circuit 8 consisting of a resistor R1 and a capacitor C. The drive blocking means is configured using a 7-year-old coupler PC, which receives the stop signal and has a 7-day transistor connected across the capacitor C.

The operation of this embodiment will be explained below. From the oscillation circuit 5, there are two output signals shown in Fig. 3 (a) and (b). Al
vB is output, and the output signal VB is sent to the drive circuit 62.
supplied to Now, when the output signal VB goes to the (no) level, the drive circuit 62 turns on the switching element Q2 in response to this signal VB. In addition, Fig. 3(b)j(e
) indicates the output V2 of the double dip circuit 62 and the current I2 flowing through the switching element Q2. At this time, since the output signal VA is at a low level, the Karen} mirror circuit 72
No current flows through. Therefore, Karen} mirror circuit 7
No current flows through , and the drive circuit 6 turns the switching element Q1 on. Then, when both outputs of the oscillation circuit 5 are inverted, the output signal VB becomes low level, so that the switching element Q2 becomes O7. At this time, a current flows through the current mirror circuit 72 due to the output signal V,. As a result, current also flows to the current mirror circuit 71, and the drive circuit 61 causes the switching element Q1 to
turns on. In addition, although the dead-off period 7 is not explained in the above explanation, the respective drive circuits 6l,
6. is switching after a predetermined time after inputting the output signal V A + V B? A delay circuit (not shown) is provided to turn on the children Q, , Q2, and the dead-off period is provided by this delay circuit.

Here, if the stop signal 3 is output from the stop signal output circuit 3, this stop signal v is input to the oscillation circuit 5, and the oscillation circuit 5 stops its operation.

At this time, both output signals V^+VB both become low level. And at the same time, the stop signal ■, is a 7 year old Tokapura PC
As a result, the 7th transistor of the 7-year-old Tocoupler PC is turned on, and by discharging the charge in the capacitor C, the control circuit 1. from the charging circuit 8. The supply of DC power E2 to is stopped. When the operation of the inverter device is stopped in this way, the supply of DC power E2 to the control circuit 11 is stopped, so even if noise is superimposed on both control circuits 1 and 12 due to foreign noise, etc., the control circuit 1
1 will not turn on switching element Q, so switching elements Q, , Q2 will not turn on simultaneously. In addition, the foreign noise is caused by the oscillation circuit 5 and 7 years old Tocoupler PC.
Stop signal output to ■3 both -7-? is superimposed on the switching element Q. , Q2 may be turned on at the same time. However, if the discharging state of the capacitor C1 is stopped due to a foreign state/is, etc., the control circuit 1l will not operate unless the capacitor C is sufficiently charged. The possibility of it turning on is extremely small and there is no problem. In addition, even if foreign noise, etc. is superimposed only on the stop signal input to the 7 Oto coupler, in this inverter device, if the main control circuit 1■ does not operate, the control circuit 1 will not operate, so simultaneous ON is not possible. Does not occur. Note that the drive blocking means 4 may be configured to turn on a switching element via a component having an insulating effect such as a transformer, or a Karen mirror circuit may be used.

[Example 2] Other embodiments of the present invention are shown in FIGS. 4 and 5.

In the inverter device of this embodiment, a drive blocking means 9 consisting of a switch means is provided between the output of the control circuit 1l and the common line of the control circuit 1, so that the control circuit 12 operates when the stop signal 1 is inputted. Has it stopped?8? When this happens, the drive blocking means forcibly lowers the output of the control circuit 11 to a low level.

A specific circuit of this embodiment is shown in FIG. This inverter device includes a detection circuit 10 that detects the output of the switching element Q, a circuit 11 that outputs a signal according to the output of the detection circuit 10, and a circuit 11 that outputs a signal according to the output of the detection circuit 10. A control circuit 12 for the switching element Q2 is configured with a timer circuit 2 which turns on the switching element Q2 for a predetermined period from the time when the switching element Q2 is turned on. In order to stop the operation of the inverter device by the stop signal, a switch means SW3 is provided between the base and emitter of the transistor used as the switching element Q2 to forcibly lower the output of the timer circuit 12 to a low level. In addition, as the control circuit h of the switching element Q, a transformer 1' is used, which also serves as the inductance of the LC resonant circuit that applies a resonant voltage to the load l, and the voltage induced in the secondary winding L2 of this transformer is The structure is such that the switching element Q is turned on at . Note that the respective switching elements Q , , Q2
Diodes D, , D, are connected in antiparallel to .

First, the basic operation of this inverter device will be briefly explained. Now, by the output of the timer circuit 12, the switching element Q
2 is turned on, current is supplied to the load 1 through the path of the DC power supply E, the load circuit 2 (the primary winding #iL of the transformer T, 1), and the switching element Q2. Then, after a certain period of time, when the switching element Q2 turns off, the primary @ of the transformer T
The energy stored in #XL is released to 2*@*L2, which turns on transistor Q1. At this time, capacitor C is connected in series to load circuit 2. Using the voltage charged in the capacitor C as a power source, a current flows through the load l in the opposite direction to that in the above case through the path of the switching element Q + % load circuit 2. When the energy in the primary winding L1 of the transformer T runs out, the transistor Q. becomes O7. The detection circuit 1 detects O7 of this transistor Q.
When 0 is detected, the trigger circuit 11 triggers the timer circuit 12, and thereafter the same operation as in the above case is repeated.

Here, in this inverter device, the circuit 1 is turned off after a certain period of time after the switching element Q1 is turned off.
A dead-off period is provided such that the output of the detection circuit 10 is input to the input terminal 1. In addition, in this inverter device, the control circuit 12 is the "main", and the control circuit 11 is the "main".
Become obedient.

The drive blocking means 9 of this embodiment is composed of a switch means SW connected between the base and emitter of the transistor of the switching element Q, and closes the switch SW in response to a stop signal 3, and closes the switch SW by a stop signal 3. Control circuit 1. When the operation of the control circuit 11 is stopped, the output of the control circuit 11 is not supplied to the switching element Q. Therefore, even in the case of this embodiment, the switching element Q. , Q2 are never turned on at the same time.

``Effect 1 of the Invention As described above, the present invention includes a drive blocking means that blocks the driving of the switching element by the output of the dependent control circuit in response to the stop signal, so that the operation of the inverter device is stopped by the stop signal. Even if foreign noise or the like is superimposed on the signal-11-12, the corresponding switching elements from the dependent control circuits will not be turned on, and therefore a power supply short-circuit condition will not occur due to simultaneous turning on of the switching elements.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram showing a schematic structure of an embodiment of the present invention, Fig. 2 is a specific circuit diagram of the same as the above, Fig. 3 is an explanatory diagram of the same as the above,
Fig. 4 is a circuit diagram showing a schematic structure of another embodiment, Fig. 5 is a specific circuit diagram of the same as above, Fig. 6 is a circuit diagram showing a schematic structure of an existing example, and Fig. 7 is a control of the same as above. FIG. 3 is a waveform diagram of an output signal of the circuit. 11=12 is a control circuit, 2 is a load circuit, 4 and 9 are drive blocking means, Q. , Q2 are switching elements, EE is a DC power supply, v 3, v . ” is a stop signal.

Claims (1)

[Claims] (1) At least a circuit in which two switching elements are connected in series is provided at both ends of a DC power supply, and a control circuit provided for each switching element alternately turns on and off the switching elements, and the output drives the load circuit with AC. In addition, in an inverter device in which the operation of one control circuit is dependent on the operation of the other control circuit, and the operation is stopped by inputting a stop signal to the main control circuit, the dependent control circuit is controlled by the stop signal. An inverter device including a drive blocking means for blocking the switching element from being driven by the output of the inverter.