KR0120290B1 - Apparatus and method for detecting short penomena of a regenerative diode - Google Patents

Abstract

A detecting apparatus and a detecting method are provided to prevent a short of regenerative diode. The detecting apparatus comprises: a short detector(10) for detecting a short of regenerative diode; a system controller(20) for outputting a control signal providing a power of a battery(1) to a DC serial motor(2) and for displaying an error to display when the short detector(10) is output a 'LOW' signal; a line contact cutoff means(30) for outputting a cutoff signal to open a line contact(RC1); and a contact controller(40) for controlling the line contact(RC1), direction contacts(RC2,RC2',RC3,RC3'), a regenerative contact(RC4) and a bypass contact(RC5) according to the control signal and the cutoff signal.

Description

Short state detection device and detection method of regenerative diode

1 is a system diagram showing a part of a power system of a general electric forklift.

2 is a block diagram of an apparatus for detecting a short state of a regenerative diode according to the present invention, connected to FIG. 1 for detecting a short state of the regenerative diode.

FIG. 3 (a) is a waveform diagram of the ogate output signal shown in FIG.

(B) is a waveform diagram of a state in which the ogate output signal shown in FIG. 2 is time delayed.

4 is a flowchart of a method for detecting a short state of a regenerative diode according to the present invention.

* Explanation of symbols for main parts of the drawings

1: Battery 2: DC serial motor

3: regenerative diode 4: accelerator

5: direction switch 10: short detection unit

20: system control unit 30: line contact breaker

40: contact control unit

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a regenerative diode short state detection device and a detection method. In a system receiving a large power supply such as an electric forklift, a regenerative diode used to recharge electric energy converted from inertial energy of a running vehicle into a battery. After detecting the short state of the regenerative diode by checking the voltage applied to the anode end of the line, if the regenerative diode is shorted, the contact point of the line switch even if the power switch is turned on to supply power to the DC serial motor. The present invention relates to a regenerative diode short state detection device and method for automatically detecting and preventing a damage that may be caused by a short circuit of the regenerative diode, while detecting and displaying a short state of the regenerative diode.

The present invention can be applied to any device that uses a regenerative diode to increase the use time of the battery by recharging the electrical energy converted from the inertial energy of the running vehicle to the battery.

FIG. 1 is a system diagram showing a part of a power system of a general electric forklift truck, in which a line processor RC1 is closed and a microprocessor moves forward contacts RC2 and RC2 'according to a driving command signal of an accelerator and a direction switch. Alternatively, the reverse contacts RC3 and RC3 'and the regenerative contact RC4 are closed, and the base terminal of the switching transistor TR1 is turned on to supply power to the battery 1 to the DC serial motor 2. On the other hand, the inertial energy of the electric forklift driven by the DC serial motor 2 is converted into electrical energy and then supplied to the battery (1) through the regenerative diode (3) to recharge the battery (1) use of the battery You can increase your time.

However, if the regenerative contact RC4 is closed in the state where the regenerative diode 3 is shorted, a large current flows, the regenerative contact RC4 is fused, the fuse F1 is blown, and the characteristics of the battery 1 are not affected. There was a problem that adversely affects.

Accordingly, the present invention is to solve the above conventional problems, by detecting the short state of the regenerative diode by checking the voltage applied to the anode terminal of the regenerative diode, and then in the case of the regenerative diode is shorted Even if the power switch is turned on to apply power, the line contactor is automatically opened to prevent damage that may be caused by the short circuit of the regenerative diode, while detecting a short state of the regenerative diode. It is an object of the present invention to provide a regenerative diode short state detection device and a detection method to display a.

In the regenerative diode short-state detection device of the present invention for achieving the above object, the microprocessor closes the direction contact and the regenerative contact according to the drive command signal of the accelerator and the direction switch after the line contact is closed and the base end of the switching transistor. Turn on to supply the battery power to the DC serial motor, while the inertial energy of the electric forklift driven by the DC serial motor is converted into electrical energy and then supplied to the battery through the regenerative diode to supply the battery. In the power supply system for recharging, comparing the voltage applied to the anode terminal of the regenerative diode and the reference voltage, if the voltage applied to the anode terminal is greater than the reference voltage outputs a low signal, the voltage applied to the anode terminal is a reference If it is less than or equal to voltage, it outputs high signal A short detection unit for detecting a short state of the load; The control signal for supplying the battery power to the DC serial motor by closing the line contact, the direction contact, the regenerative contact, and the bypass contact according to the driving command signal of the accelerator and the direction switch, and turning on the base end of the switching transistor. A system controller which displays an error on a display unit such as an LED or an LCD when a low signal is output from the short detector; A line contact breaker for outputting a cutoff signal for opening a line contact regardless of a control signal of a system controller when a row is output from the short detector; And a contact controller for controlling a line contact, a direction contact, a regenerative contact, and a bypass contact according to the control signal and the blocking signal.

On the other hand, the regenerative diode short-state detection method of the present invention includes the steps of determining whether the forward control signal, the reverse control signal and the regeneration control signal output from the microprocessor are all zero; Determining whether the voltage applied to the anode terminal of the regenerative diode is high when the forward control signal, the reverse control signal, and the regeneration control signal are both zero; If the voltage applied to the anode end of the regenerative diode is high, determining whether the duration of the high state is less than the set time, and returning to the initial stage if the duration of the high state is less than the set time; If the duration of the high state is equal to or greater than the set time, outputting a line contact control signal low and displaying an error indication; If both the forward control signal, the reverse control signal and the regeneration control signal are not zero, or the voltage applied to the anode terminal of the regenerative diode is low, the initialization flow is performed, and the operation returns to the initial stage. do.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a system diagram showing a part of a power system of a general electric forklift, and FIG. 2 is a block diagram of an apparatus for detecting a short state of a regenerative diode according to the present invention, connected to FIG. 1 to detect a short state of the regenerative diode. When the key switch SW1 that is turned on to supply power, the fuse F1 that blocks the overcurrent flowing in the line, and the key switch SW1 are turned on, the battery 1 is charged and charged at both ends. When the electrolytic capacitor C and the transistor TR2 are turned on, a current flows through the coil L2 to close the line contact RC1, and when the transistor TR3 is turned on, a current flows through the coil L3 to close the bypass contact ( RC5, forward contacts RC2 and RC2 ', in which current flows to coil L4 when the transistor TR4 is turned on; and reverse contacts RC3, in which current flows to coil L5 and is closed when the transistor TR5 is turned on. , RC3 '), and the forward contacts RC2 and RC2' When the reverse contacts RC3 and RC3 'are closed, the DC serial motor 2 which is driven to reverse and the inertia energy of the DC serial motor 2 are converted into electrical energy are supplied to the battery 1 and recharged. The regenerative diode 3 is provided.

In FIG. 1, the diode D1 is a freewheel diode for freewheeling, the diode D2 is a plugging diode, and the DC serial motor 2 is the accelerator 4 of FIG. And direction switch (5).

Of FIG. 1 Of the second degree Are connected to each other.

2, the short state detection apparatus of the regenerative diode according to the present invention compares the voltage applied to the anode terminal of the regenerative diode 3 with the reference voltage, and if the voltage applied to the anode terminal is greater than the reference voltage, A short detector 10 which outputs a signal and outputs a high signal when the voltage applied to the anode terminal is less than or equal to the reference voltage to detect a short state of the regenerative diode; Close the line contact RC1, the direction contacts RC2, RC2 ', RC3, RC3', the regenerative contact RC4, and the bypass contact RC5 according to the driving command signals of the accelerator 4 and the direction switch 5. Outputs a control signal for supplying power of the battery 1 to the DC serial motor 2 by turning on the base terminal of the switching transistor TR1, and outputting a low signal from the short detector 10; A system control unit 20 for displaying an error on display means such as an LED or an LCD; A line contact breaker 30 outputting a cutoff signal for opening the line contact RC1 regardless of a control signal of the system controller 20 when a row is output from the short detector 10; And a contact controller 40 for controlling the line contact RC1, the direction contacts RC2, RC2 ′, RC3 and RC3 ′, the regenerative contact RC4, and the bypass contact RC5 according to the control signal and the cutoff signal. It is configured by.

In addition, the short detector 10 may include a terminal connected to an anode end of the regenerative diode 3. Zener diode ZD1 outputting a current through the input of a voltage through a predetermined value and the output voltage of the zener diode ZD1 is 0 when the output voltage of the zener diode ZD1 is compared with a reference voltage. Comparator (OP-amp) for outputting, and the diode (D3) and the resistor (R1 ~ R4) and capacitor (C1) for generating the overvoltage and noise generated during the regeneration.

In addition, the system control unit 20 includes a microprocessor (MCU). On the other hand, the line contact breaker 30, the ora gate (U1) for the output of the forward control signal, reverse control signal, recurrence control signal output from the microprocessor (MCU), and the output signal of the oragate (U1) The output signal of the diode D4, the resistor R9, the capacitor C4, and the oar gate U1 to match the contact delay time with the comparator (OP-amp) output of the short detector 10 Noah gate (U2), and the output of the noah gate (U2) is a high SCR is turned on, and resistors (R6, R7) and capacitor (C2) for preventing overvoltage and noise.

Referring to Figure 4 the operation and effect of the present invention configured as described above in detail as follows.

In order to detect the short state of the regenerative diode when the system is in the initial state, the microprocessor (MCU) turns on the SCR by driving the gate of the SCR. The MCU reads the short state of the regenerative diode 3 through the short detection unit 10 and outputs a line contact control signal to close the line contact RC1.

At this time, since the SCR is turned on, the AND gate U6 outputs a low signal, and the transistor TR2 is turned off so that no current flows in the coil L2, so the line contact RC1 is open.

Referring to the above operation in more detail as follows.

FIG. 3A is a waveform diagram of the oragate output signal shown in FIG. 2, and (B) is a waveform diagram of a time delayed state of the oragate output signal shown in FIG. 2. The key switch SW1 is shown in FIG. ) Is turned on, the forward contact signals RC2 and RC2 'and the reverse contact RC3 and RC3' operated according to the forward control signal and the backward control signal and the regeneration control signal output from the microprocessor (MCU); Since regenerative contact RC4 is actually open after tens of ns, it is delayed by diode D4, resistor R9, and capacitor C4 to match this delay time, and becomes low during T1 to T2 hours. It is applied to the noah gate U2.

Even when the control signal for controlling each contact point is output from the microprocessor (MCU) as described above, when the voltage applied to the adonode terminal of the regenerative diode 3 is high, the comparator (OP-amp) of the short detector 10 is provided. ) Output goes low, so the output of the no-gate U2 always goes high.

Therefore, since the high signal output from the no-agate U2 turns on the SCR, and the signal applied to the AND gate U6 is switched from the high state to the low state, the AND gate U6 is the transistor TR2. Since the transistor TR2 is inhibited, no current flows in the coil L2 so that the line contact LC1 is opened.

In the above, once the SCR is turned on, the state of the SCR is always maintained until the key switch SW1 is turned off, and the resistor R8 and the capacitor C3 are used to drive the SCR in the on state. .

Meanwhile, the microprocessor (MCU) reads the low signal when the short detector 10 outputs the low signal and displays the regenerative diode 3 in the short state on a display unit such as an LED or an LCD.

When the DC serial motor 2 normally driven is stopped, the base terminals of the transistors TR2 are inhibited, and then the direction contacts RC2, RC2 ', RC3, RC3' and the regenerative contact ( RC4) must be open. At this time, the microprocessor (MCU) converts the forward control signal, the backward control signal and the regeneration control signal from high to low.

Table 1 shows the cross / open state of the line contact RC1 according to the forward control signal, the backward control signal and the regeneration control signal of the microprocessor (MCU), and the anode input signal of the sacrificial diode 3. .

The present invention operating as described above will be described again with reference to the flowchart of FIG.

Determining whether the forward control signal, the backward control signal, and the regeneration control signal output from the microprocessor are all zero (S1); Determining whether the voltage applied to the anode terminal of the regenerative diode is high when the forward control signal, the backward control signal, and the regeneration control signal are both zero (S2); If the voltage applied to the anode terminal of the regenerative diode is high, it is determined whether the duration of the high state is less than the set time (X). If the duration of the high state is less than the set time (X), the initial stage S1 is determined. Return step (S3); If the duration of the high state is equal to or greater than the set time (X), outputting the line contact control signal low and displaying an error indication (S4); If both the forward control signal and the reverse control signal and the regeneration control signal are not zero or the voltage applied to the anode terminal of the regenerative diode is low, the initialization flow is performed and the process returns to the initial step S1 and step S5. By sequentially operating, the short state of the regenerative diode can be detected and displayed.

As described above, according to the present invention, a short circuit state of the regenerative diode is detected by checking a voltage applied to the anode terminal of the regenerative diode, and when the regenerative diode is shorted, a power switch for supplying power to the DC serial motor. Even if it is turned on, the line contactor is automatically opened to prevent damage that may be caused by the short circuit of the regenerative diode, and the short state of the regenerative diode is detected and displayed.

Claims (2)

After the line contact RC1 is closed, the microprocessor closes the forward contact RC2, RC2 'or the reverse contact RC3, RC3' and the regenerative contact RC4 according to the drive command signal of the accelerator and the direction switch. The power supply of the battery 1 to the DC serial motor 2 by turning on the base end of the switching transistor TR1, and the inertia of the electric forklift truck driven by the DC serial motor 2 Energy is again converted into electrical energy and then supplied to the battery (1) through the regenerative diode (3) to recharge the battery (1), the voltage applied to the anode end of the regenerative diode (3) When the voltage applied to the anode terminal is greater than the reference voltage, a low signal is output. When the voltage applied to the anode terminal is less than or equal to the reference voltage, a high signal is output to short the regenerative diode. A short detection unit 10 for detecting a state; Close the line contact RC1, the direction contacts RC2, RC2 ', RC3, RC3', the regenerative contact RC4, and the bypass contact RC5 according to the driving command signals of the accelerator 4 and the direction switch 5. Outputs a control signal for supplying power of the battery 1 to the DC serial motor 2 by turning on the base end of the switching transistor TR1, and outputting a low signal from the short detection unit 10. System control unit 20 for displaying an error on display means such as an LED or LCD; A line contact breaker 30 outputting a cutoff signal for opening the line contact RC1 regardless of a control signal of the system controller 20 when a row is output from the short detector 10; And a contact controller 40 for controlling the line contacts RC1, the direction contacts RC2, RC2 ', RC3, and RC3', the regenerative contact RC4, and the bypass contact RC5 according to the control signal and the cutoff signal. Short state detection device for a regenerative diode, characterized in that configured to. Determining whether the forward control signal, the backward control signal, and the regeneration control signal output from the microprocessor are all zero (S1); Determining whether the voltage applied to the anode terminal of the regenerative diode is high when the forward control signal, the backward control signal, and the regeneration control signal are both zero (S2); If the voltage applied to the anode terminal of the regenerative diode is high, it is determined whether the duration of the high state is less than the set time (X). If the duration of the high state is less than the set time (X), the initial stage S1 is determined. Returning step S3; If the duration of the high state is equal to or greater than the set time (X), outputting the line contact control signal low and displaying an error indication (S4); If both the forward control signal and the reverse control signal and the regeneration control signal are not zero or the voltage applied to the anode terminal of the regenerative diode is low, the initialization flow is performed, and the process returns to the initial step S1 and step S5. A short state detection method for a regenerative diode, which is sequentially operated.