KR20220132117A - Energy saving monitoring method and apparatus therefor - Google Patents

Abstract

The present invention relates to an energy saving monitoring method and apparatus therefor. The energy saving monitoring method, according to the present invention, comprises the steps of: measuring three-phase currents of an inverter and transmitting the three-phase currents to a calculation unit (S10); calculating and normalizing an average value of the measured three-phase current values and generating a failure detection variable (S20); comparing the failure detection variable with a threshold value to determine whether there is a failure (S30); and finally identifying whether or not there is an open failure of an IGBT of the inverter (S40). Therefore, the present invention can minimize heat loss and energy consumption.

Description

Energy saving monitoring method and apparatus therefor

The present invention relates to an energy saving monitoring method and apparatus, and more particularly, to energy saving monitoring that can reduce real-time status check and maintenance costs through open failure diagnosis of an IGBT (Insulated Gate Bipolar Transister) mounted on an inverter. It relates to a method and an apparatus therefor.

Since the inverter can rotate the motor at a constant speed even when the power is somewhat unstable, it can have advantages such as energy saving, productivity improvement, and simple operation.

In the case of such an inverter, the speed of the motor can be controlled by power conversion using a power semiconductor.

Among these inverters, recently 3-phase PWM (Pulse Width Modulation) is widely used in various industrial fields such as variable speed motor control, uninterruptible power supply, and active power filter.

However, the power semiconductor switch, which is a major component of the inverter, may fail due to unexpected overheating, mechanical and electrical stress, and a diagnostic technique for securing system reliability and safety is required.

Therefore, until now, such inverter failure types are frequently treated as simple failures without identification, causing economic losses, and there may be a problem in that control performance and efficiency in the system are lowered, and other power devices Accidents have occurred in which the entire system is shut down along with a problem that causes stress.

(0001) Korean Patent Laid-Open Publication No. 10-2009-0125481 (Inverter failure detection device and method, 2009.12.07)

The present invention has been devised to solve the above problems, and it is possible to solve the switch open failure among failure types according to the failure types of the PWM inverter and to provide an economical and efficient improvement method for the failure of the PWM inverter. aim to do

1(a) and 1(b) are graphs showing the frequency of occurrence of each failure type of a PWM inverter.

Referring to Fig. 1(a), the failure of the PWM inverter accounts for 34% of the power switching element, 30% of the capacitor, and 26% of the PCB failure, so the failure of the power switching element is the most common cause of failure. can

As described above, the failure types of the IGBT, which are switches, can be divided into short-circuit failures and open failures.

In the case of a short circuit failure of this type, the short circuit causes an overcurrent and may result in the system stopping. In the case of such a short-circuit failure, it can be said that it can be prevented by using a protection circuit using hardware. There has been a problem that

In particular, there has been a problem in that stress accumulates in other devices, causing secondary failure, or incurring a cost of stopping and repairing the system.

Energy saving monitoring method according to an embodiment of the present invention, in the energy saving monitoring method for the injection molding machine, measuring the three-phase current of the inverter through the sensor of the measuring unit and transmitting the three-phase current to the calculation unit (S10); calculating and normalizing the average value of the phase current values, and generating a failure detection variable (S20); and determining whether a failure occurs by comparing the failure detection variable with a threshold value (S30); and finally identifying the presence or absence of an open failure of the IGBT among the inverters (S40), wherein the switch mounted on the inverter is an insulated gate bipolar transistor (IGBT), and the signal used by the main controller is connected to the IGBT It is a current signal, and it can replace the speed sensor by calculating the operating speed of the motor based on the current signal and the voltage signal. It is possible to minimize heat loss and energy consumption through the introduction of a modulation technique that can reduce It may be to minimize energy consumption by receiving feedback in real time.

An energy saving monitoring method according to an embodiment of the present invention, in the energy saving monitoring method for a vehicle, measuring the three-phase current of the inverter through a sensor of the measuring unit and transmitting the three-phase current to the calculation unit (S10); Calculating and normalizing the average value of the phase current values, and generating a failure detection variable K _N (S20); and comparing the failure detection variable K _N with the first threshold value th1 to determine whether there is a failure (S30) ); and finally identifying the presence or absence of an open failure of the IGBT among the inverters (S40), wherein the switch mounted on the inverter is an insulated gate bipolar transistor (IGBT), and the signal used by the main controller is connected to the IGBT It is a current signal, and it can replace the speed sensor by calculating the operating speed of the motor based on the current signal and the voltage signal. It is possible to minimize heat loss and energy consumption through the introduction of a modulation technique that can reduce This may be to minimize energy consumption.

In one embodiment of the present invention, it may be possible to minimize the loss (loss) due to inverter non-operation by detecting the state of the hardware in real time and automatically notifying it through the app when an abnormality is detected.

In the energy saving monitoring apparatus according to an embodiment of the present invention, in the energy saving monitoring apparatus, a measuring unit for measuring a three-phase current; and calculating and converting the current values measured by the measuring unit to calculate an average value a calculation unit for performing the calculation; and a fault detection unit for detecting whether an IGBT open failure occurs using the calculation result of the calculation unit; and a failure identification unit that identifies which IGBT is a failure when the failure detection unit detects an IGBT open failure, a monitor capable of confirming the operating state of the IGBTs in real time, and a real-time energy consumption estimate through the monitor It may be one that can minimize energy consumption by further including a real-time sensing unit that can.

In one embodiment of the present invention, the IGBT is a collector voltage value applied to a collector of the IGBT controlled by receiving a PWM signal, a collector current value flowing through the collector of the IGBT, and the time elapsed from the time when the PWM signal is input. It may be to receive an elapsed time value that is time from the IGBT driver.

According to an embodiment of the present invention, in a circuit including a PWM inverter, by detecting a signal generated from the main controller, it is possible to check the current abnormality by checking whether the IGBT included in the PWM inverter is in a normal state. Therefore, it is possible to check the operation status of the PWM inverter in an easy and convenient way, and to accurately determine the fault point for the PWM inverter.

According to the energy saving monitoring apparatus according to an embodiment of the present invention, it may be possible to minimize energy consumption by further including a real-time sensing unit capable of estimating the energy usage in real time through the monitor.

1(a) and 1(b) are graphs showing the frequency of occurrence of each failure type of a PWM inverter.
2 is a block diagram showing the configuration of a general inverter.
3 is a diagram showing the αβ axis current i _αβ according to the phase angle in the stationary coordinate system according to an embodiment of the present invention.
4 is a view showing a three-phase PWM inverter system according to an embodiment of the present invention.
5 is a view showing a situation of a home dashboard using an energy saving monitoring device according to an embodiment of the present invention.
6 is a diagram illustrating a case in which an energy saving monitoring apparatus according to an embodiment of the present invention is applied to a vehicle.
7 is a block diagram illustrating a partial configuration of an energy saving monitoring apparatus according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. However, the present invention may be embodied in several different forms, and is not limited to the embodiments described herein. And in order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification.

Terms used in this specification will be briefly described, and the present invention will be described in detail.

The terms used in the present invention have been selected as currently widely used general terms as possible while considering the functions in the present invention, but these may vary depending on the intention or precedent of a person skilled in the art, the emergence of new technology, and the like. In addition, in a specific case, there is a term arbitrarily selected by the applicant, and in this case, the meaning will be described in detail in the description of the corresponding invention. Therefore, the term used in the present invention should be defined based on the meaning of the term and the overall content of the present invention, rather than the name of a simple term.

In the entire specification, when a part "includes" a certain component, it means that other components may be further included, rather than excluding other components, unless otherwise stated. In addition, terms such as "unit" and "module" described in the specification mean a unit that processes at least one function or operation, which may be implemented as hardware or software, or a combination of hardware and software. In addition, when a part is "connected" to another part throughout the specification, this includes not only a case in which it is "directly connected" but also a case in which it is connected "with another element in the middle".

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

The present invention relates to a method for saving energy while actively coping with a failure situation of a PWM inverter that may occur in the case of managing the energy of a factory or an entire building.

2 is a diagram illustrating a fault diagnosis method in an energy saving system according to an embodiment of the present invention.

Referring to FIG. 2 , the fault diagnosis method may be largely composed of two parts: fault detection and fault identification. Failure detection is a part of detecting an IGBT failure when it occurs, and failure identification is a part of determining a malfunctioning IGBT. The current i _abc on the output of the inverter and the current value i ^* _αβ in the stationary coordinate system can be input for fault diagnosis.

i _abc and i ^* _αβ are information used for basic current control of the inverter, and only these current information can be used in the fault diagnosis method. The fault can be diagnosed independently without

Referring to the method for detecting a fault in the inverter according to an embodiment of the present invention with reference to FIG. 2 , the three-phase current i _abc measured through the measuring unit 10 and the current value i ^* _αβ in the stationary coordinate system are faulty It can be an input for diagnosis.

_. i _abc and i ^* _αβ are information used for basic current control of the inverter, and since only these current information is used in the fault diagnosis method, in the energy saving monitoring method according to an embodiment of the present invention, the relationship between the operating conditions of the inverter The fault can be diagnosed independently without

Referring to FIG. 2, in the energy saving monitoring method according to an embodiment of the present invention, the three-phase current i _abc measured by the measuring unit 10 is converted to the stationary coordinate system αβ axis current i _αβ as shown in [Equation 1]. Conversion is possible.

Accordingly, the phase angle θ may be calculated as in Equation (2).

[Equation 1]

i _α =i _a

i _β =1/√3(i _a +2i _b )

[Equation 2]

4 is a view showing the αβ axis current i _αβ according to the phase angle in the stationary coordinate system according to an embodiment of the present invention.

Referring to FIG. 4 , the stationary coordinate system current i _αβ obtained from the three-phase current i _abc is a sinusoidal current, so the vector phase angle θ may rotate at a constant speed from 0 degrees to 360 degrees. The time in which the vector phase angle is divided into six portions at a constant speed may be the same.

However, when a failure occurs in the energy saving monitoring device according to an embodiment of the present invention, the three-phase current is distorted, and accordingly, the vector phase angle θ may also be distorted.

To put it more simply, the failure of the IGBT switch can be detected because there is a difference in the time that each sector section exists.

The IGBT switch is a switching power device capable of quickly performing a switching operation to block or allow an electric flow.

When a high voltage is applied to the IGBT while the IGBT is turned on, the current flowing through the collector of the IGBT may rapidly increase, causing the IGBT to be short-circuited. The IGBT driver 25 for driving the IGBT to prevent failure of the IGBT due to a short circuit of the IGBT may measure a collector voltage applied to the collector of the IGBT and a current flowing through the collector of the IGBT.

a receiver receiving a collector voltage value applied to a collector of an IGBT controlled by receiving a PWM signal, a collector current value flowing through the collector of the IGBT, and an elapsed time value that is a time elapsed from the time when the PWM signal is inputted from the IGBT driver; and an error rate indicating a probability that the operation state of the IGBT is a short circuit, a plurality of membership functions indicating membership degrees of a plurality of fuzzy sets corresponding to each of the collector voltage value, the collector current value, and the elapsed time value; Based on a fuzzy rule composed of a combination of each fuzzy set, fuzzy inference is performed on the collector voltage value, the collector current value, and the elapsed time value, and the operation state of the IGBT is determined based on the result of the performed fuzzy inference. It may include an operation state determination unit 120 to determine.

The IGBT 15 may include a collector, an emitter, and a gate. For reference, the IGBT 15 may be provided inside the vehicle to perform a switching operation. For example, the IGBT may be provided in an ignition switch, a motor, and a voltage plug inside a vehicle to perform a switching operation.

In addition, the IGBT may be controlled by receiving a PWM signal from the IGBT driver 25 .

For example, the IGBT can be turned on when a PWM signal is applied from the IGBT driver. And the IGBT can be turned on when a PWM signal is input from the IGBT driver. And the IGBT may be turned off when no PWM signal is input from the IGBT driver.

In addition, the IGBT driver 25 may measure a collector voltage value applied to the collector of the IGBT 15 and a collector current value flowing through the collector of the IGBT 15 . Also, the IGBT driver 25 may measure an elapsed time value, which is a time elapsed after the PWM signal is applied to the IGBT 15 .

Referring to FIG. 3 , the IGBT driver 25 may provide a collector voltage value, a collector current value, and an elapsed time value to the IGBT operation state determination apparatus 100 . Accordingly, the IGBT operation state determination apparatus 100 may determine the operation state of the IGBT 15 using all of the collector voltage value, the collector current value, and the elapsed time value. In addition, the apparatus 100 for determining the operation state of the IGBT may determine whether the IGBT 15 has failed using all of the collector voltage value, the collector current value, and the elapsed time value.

Specifically, referring to FIG. 3 , the IGBT operation state determination apparatus 100 may include a receiver 110 and an operation state determination unit 120 .

The receiver 110 receives the PWM signal and controls the IGBT 15 using the collector voltage value applied to the collector, the collector current flowing through the IGBT 15 collector current, and the elapsed time value. operation status can be determined. In addition, the IGBT operation state determination apparatus 100 may receive a time value elapsed from the time when the PWM signal is input from the IGBT driver 25 .

Specifically, the receiver 110 may be connected to the IGBT driver 25 through a conductive wire. The receiver 110 may receive the collector voltage value, the collector current value, and the elapsed time value from the IGBT driver 25 as an analog signal or a digital signal. In addition, the receiving unit 110 may provide the collector voltage value, the collector current value, and the elapsed time value to the operation state determination unit 120 .

The operation state determination unit 120 may perform fuzzy inference on the collector voltage value, the collector current value, and the elapsed time value based on a fuzzy rule including a combination of a plurality of membership functions and a plurality of fuzzy sets, respectively. In addition, the operation state determination unit 120 may determine the operation state of the IGBT 15 based on the result of the performed fuzzy inference.

Here, the plurality of membership functions include the degree of membership of a plurality of fuzzy sets corresponding to the collector voltage value, the collector current value, the elapsed time value, and the error rate indicating the probability that the operation state of the IGBT 15 is a short circuit. It may be a function representing

Therefore, as in [Equation 3], a variable k can be defined that compares the sector number with the previous value for every sampling, stores a value of 1 if it does not change, and initializes it to 0 when the sector number changes.

[Equation 3]

k=k _k-1 +1 if)S _k =S _k-1

k=0 if)S _k ≠S _k-1

That is, the average value <k> can be generated by calculating the average value of the variable k. If the inverter switch operates normally, <k> can be kept constant. However, when the IGBT, which is the inverter switch, fails, the phase angle of the vector exists only in a specific sector, so the specific sector time becomes longer and <k> may increase.

If the magnitude or frequency of the current i _abc flowing through the inverter is changed due to a load change in the energy saving monitoring device according to an embodiment of the present invention, the rotation speed of the vector phase angle is also changed, so <k> may also be changed. .

In this case, even though the IGBT switch operates normally, an error that is determined as a failure may occur. Therefore, a normalization process for load fluctuations may be necessary.

The normalization of <k> can be obtained from the value of the current controller. That is, the vector phase value θ ^* can be obtained through Equation 4 from the current i ^* _αβ of the stationary coordinate system through Equation 4.

[Equation 4]

As in [Equation 3], by calculating [Equation 5] through [Equation 4], the section S ^* and variable k ^* of θ ^* can be calculated.

[Equation 5]

k*=k* _k-1 +1 if)S* _k =S* _k-1

k=0 if)S* _k ≠S* _k-1

As shown in <Equation 6>, if <k> is divided by the average value of k ^* <k*>, it is possible to obtain a normalized failure detection variable K _N that is independent of transient conditions such as load fluctuations and can detect IGBT failures. do. Therefore, if the IGBN operates normally, <k> and <k*> have the same value, so K _N has a value of 1. If the IGBN is faulty, <k> increases compared to <k ^* >.

[Equation 6]

K _N =<k>/<k*>

Therefore, to detect the failure of the IGBT, the failure detection variable K _N is Compared with the first threshold value th1, if K _N does not exceed the first threshold value, it may be determined as a normal operation, and if it exceeds the first threshold value th1, it may be determined as a failure.

That is, when the IGBT operates normally, K _N =1 is maintained, and when a failure occurs, K _N increases to 1.5 or more. Therefore, the first threshold value th1 may be determined in the range of 1<th1<1.5.

The closer the first threshold value is determined to 1, the faster the failure detection speed, but since the margin with K _N becomes narrower, a failure signal can be generated even though it is not a failure.

In addition, as the first threshold value th1 approaches 1.5, the failure detection speed becomes slower, but robustness against transient conditions such as load fluctuations or disturbances may increase. In general, the first threshold value may be determined to be 1.3 so that the detection speed is also secured while ensuring sufficient robustness.

Referring to FIG. 2 , looking at a method for fault identification in an inverter according to an embodiment of the present invention, as a second step in diagnosing an inverter fault, first, when a fault of an inverter switch is detected, it is determined which switch is faulty Fault identification may be necessary to

IGBT failure identification according to an embodiment of the present invention may be performed through two identification variables.

One is to identify a phase open fault, that is, when one phase of the inverter is open, and the other is to identify a case where a failure occurs in both the upper and lower switches of the same phase among A, B, and C phases. This is to identify the occurrence of multiple open faults in the switch, and it is to identify the case in which an open fault has occurred in one or more switches.

5 is a view showing a three-phase PWM inverter system according to an embodiment of the present invention.

Referring to FIG. 5 , Vdc is a DC power supply voltage, ia, ib, and ic are A, B, and C phase currents, respectively, and an induction motor may be used as a load.

Referring to the method for fault identification in the inverter according to an embodiment of the present invention with reference to FIG. 2 , as a second step of diagnosing an inverter fault, when a fault of an IGBT switch is detected, determining which IGBT is faulty identification may be required for

Referring to FIG. 2 , for identifying a phase open failure in the inverter according to an embodiment of the present invention, each current of the three phases of the inverter is assumed to be an ideal sine wave and can be expressed as [Equation 7].

[Equation 7]

는 초기 위상각을 나타낸다. 각 상전류에 정규화 과정을 거치면, 다음 수학식 8과 같이 표현될 수 있다.In Equation 7, I _M is the current maximum value, w _e is the current angular frequency,

denotes the initial phase angle. When each phase current is subjected to a normalization process, it can be expressed as in Equation 8 below.

[Equation 8]

By using the difference between the other two phase currents as in [Equation 9] using the normalized current, the identification variable of the phase open failure can be calculated.

[Equation 9]

[Equation 10]

(In [Equation 10], T may mean one cycle of the sinusoidal current.)

If the switch is normal without a phase open failure, the absolute value of the difference between the phase currents of phase A and phase B becomes 1.1 according to [Equation 10], so that the phase open failure identification variable P _n can always be maintained at 0 when normal. If a fault occurs in phase C among three phases, the currents in phase A and phase B are reversed with opposite signs according to Kirch's law, and the magnitudes can be the same.

이 되고, 그 절대값은 √3이 되므로, 상 개방고장의 식별 변수 Pn은 0.632(=√3-1.1)가 될 수 있다. 즉, 상 개방고장 식별 변수Pn 이 0이면 인버터는 정상 상태이고, 이 0632 값을 가지면 상 개방고장 상태가 되므로, 을 제 2 임계값(th2)와 비교함으로써, 상 개방고장을 식별할 수 있다. 여기에서, 도 4에서 스위치 S1이나 S2 둘 중 하나만 고장이 발생했다면, Pa는 약 0.3~0.35의 값을 가지게 되므로, 제 2 임계값(th2)는 0.35<th2<0.632의 범위에서 결정될 수 있다 In other words

, and its absolute value becomes √3, the identification variable Pn of the phase open failure can be 0.632 (=√3-1.1). That is, if the phase open failure identification variable Pn is 0, the inverter is in a normal state, and if it has a value of 0632, it is in a phase open failure state. Here, if only one of the switches S1 or S2 in FIG. 4 fails, Pa has a value of about 0.3 to 0.35, so the second threshold value th2 may be determined in the range of 0.35 < th2 < 0.632.

In case of multiple open fault, the phase current of the corresponding phase exists only in positive (+) half cycle or negative (-) half cycle depending on the faulty switch among the 6 IGBTs constituting the inverter. Therefore, the identification of the faulty switch can be grasped through the sign of the measured three-phase current.

By introducing the sign determining variable l _n for the three-phase current and calculating the average for one cycle of the sign determining variable l _n , if the average during one cycle of the sign determining variable is 0, it can be determined that the inverter operates normally, If it has a certain constant value, it can be determined that the switch is faulty. That is, the average during one cycle of the sign decision variable l _n becomes a multi-switch failure identification variable Ln that can identify multiple phase switch failures.

In order to introduce the sign determining variable for the three-phase current, it is necessary to define a third threshold value th3 serving as a reference for determining the sign of the three-phase current signal. That is, as in <Equation 11>, when the absolute value of each phase current is less than the third threshold value th3, it is defined as 0, and when the absolute value of each phase current is equal to or greater than the third threshold value th3, it is defined as 1, If the sign is different, it can be defined as -1.

[Equation 11]

Theoretically, the third threshold value th3 is to determine the sign of the three-phase current signal by comparing it with the measured current value, so the third threshold value th3 is set to 0, and if the measured current signal is greater than 0, ln=1 is defined and, if it is small, it may be easier to calculate the sign discrimination by defining ln=-1. However, since the third threshold value th3 is compared with the actual measured current value, the third threshold value th3 cannot be theoretically determined as the current value 0, but can be determined in consideration of the actual current value having an offset component such as noise. That is, it may be accurate that the third threshold value th3 is determined to have as small a value as possible, but if it is determined too small, it becomes sensitive to noise included in the current signal. Considering this, it can be determined as about 2~5% of the rated current value.

Therefore, the multi-switch failure identification variable Ln can be expressed as the average value of the sign determining variable ln, ie, the average during one cycle as shown in Equation 12.

[Equation 12]

When the inverter operates normally, each phase current is a sine wave, so the multi-switch fault identification variable Ln = 0, and in the case of an IGBT failure, the fault identification variable of the corresponding phase becomes Ln = ±0.5 depending on the faulty switch.

For example, if the upper IGBT S1 of A-phase is faulty, the A-phase current has only 0 for positive (+) half cycle and negative (-) for negative (-) half cycle, so La of fault identification variable Ln is about -0.5 Conversely, if the lower IGBT S2 of phase A is faulty, La becomes about +0.5. At this time, Lb and Lc have values of 0.2 to 0.3.

Accordingly, by comparing the multi-switch failure identification variable Ln with the fourth threshold value th4, it is possible to determine the failure switch. As in the above example, if the upper IGBT S1 of phase A fails, La has a value of about -0.5, and Lb and Lc have values of 0.2 to 0.3, so the fourth threshold value th4 is in the range of 0.3 < th4 < 0.5 can be determined from That is, if the value of the multi-switch failure identification variable La is less than the fourth threshold value th4, the A-phase IGBT is in a normal state, and if the value of the identification variable is greater than the fourth threshold value th4, it is determined that the A-phase IGBT is in an open failure state. can

Table 1 is a table showing the number of identifiable cases for an open failure of the inverter IGBT. In Table 1, in order to indicate the number of identifiable open failures of the IGBT, in Equations 13 and 14, the failure detection variable and the multi-switch failure identification variable are expressed by defining symbols.

[Equation 13]

[Equation 14]

[Table 1]

Referring to [Table 1], open faults are classified into 5 groups, and one IGBT fault, phase open fault, upper and lower IGBT failures of two phases respectively, upper (lower) IGBT of two phases and lower (upper) of the other phase A total of 27 cases of open failure can be identified as IGBT failure, open failure of one phase, and upper and lower IGBT failures of two phases, respectively. In Table 1, [] means that the corresponding IGBT is faulty or normal, and (|) means that both are faulty or at least one is faulty.

Referring to Table 1 and <Equation 13> and <Equation 14>, when all of the phase open failure identification variables Pn are N, there is no IGBT faulty in the same phase, and F in any one of the phase open failure identification variables Pn. In this case, it can be determined that an IGBT failure has occurred in one phase.

In addition, referring to Table 1 and <Equation 13> and <Equation 14>, when the multi-switch failure identification variable Ln is 0, there is no faulty switch, and in the case of H or L, it is determined that the switch of the corresponding phase is faulty can do.

As described above, based on the results of the six IGBTs, the status of the circuit can be determined in real time, and the presence or absence of a failure and the operation status can be displayed for each facility in real time.

6 is a view showing a situation of a home dashboard using an energy saving monitoring device according to an embodiment of the present invention.

Referring to FIG. 6, it is possible to know the failure status of six IGBTs disposed in facility 1 and facility 2, and it is possible to check the energy consumption and cost calculation amount for each period (that is, monthly, daily, weekly). It may be possible.

If it is assumed that this system is applied to the injection machine, the sensorless vector control method and the method of receiving analog signals for flow and pressure in real time are used to provide appropriate flow and pressure according to the process conditions to minimize energy consumption. results can be obtained.

7 is a diagram illustrating a case in which the energy saving monitoring apparatus according to an embodiment of the present invention is applied to a vehicle.

Referring to FIG. 7 , by applying an Energy Storage System (ESS), the operating speed can be maintained at a constant speed during driving, and a system that can save energy by lowering the idling rpm when the vehicle is stopped can be constructed.

In addition, it can be configured to minimize the loss due to inverter non-operation by detecting the hardware status in real time and automatically notifying it through the app when an abnormality is detected.

8 is a block diagram showing a partial configuration of an energy saving monitoring apparatus according to an embodiment of the present invention.

Referring to FIG. 8 , in the energy saving monitoring apparatus, a measuring unit 10 for measuring a three-phase current; and a calculating unit 20 for calculating and converting current values measured by the measuring unit to calculate an average value ); and a failure detection unit 30 for detecting whether there is an IGBT open failure using the calculation result of the calculation unit 20; and a fault identification unit 40 that identifies which IGBT is faulty when the fault detection unit 30 detects an IGBT open failure, and a monitor 110 that can check the operating status of the IGBTs in real time; It may further include a real-time sensing unit 120 capable of estimating energy usage in real time through a monitor.

The foregoing description of the present invention is for illustration, and those of ordinary skill in the art to which the present invention pertains can understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. will be.

Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. For example, each component described as a single type may be implemented in a dispersed form, and likewise components described as distributed may be implemented in a combined form.

The scope of the present invention is indicated by the following claims rather than the above detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention. do.

10: measurement unit 20: calculation unit
30: fault detection unit 40: fault identification unit

Claims (6)

In the energy saving monitoring method for the injection machine,
measuring the three-phase current of the inverter through the sensor of the measuring unit and transmitting it to the calculating unit (S10);
calculating and normalizing the average value of the measured three-phase current values, and generating a failure detection variable K _N (S20);
determining whether a failure occurs by comparing the failure detection variable K _N with the first threshold value th1 (S30); and
Including; finally identifying the presence or absence of an open failure of the IGBT among the inverters (S40);
The switch mounted on the inverter is an IGBT (Insulated Gate Bipolar Transistor),
The signal used by the master controller is the current signal connected to the IGBT,
It is possible to replace the speed sensor by calculating the operating speed of the motor based on the current signal and the voltage signal,
The control method corresponds to sensorless vector control, and it is possible to minimize heat loss and energy consumption through the introduction of a modulation technique that can reduce the harmonic content through IGBT, which is a power switching device,
It is possible to determine the operating status of the IGBTs in real time,
Energy saving monitoring method for injection molding machines, characterized in that it is possible to measure the amount of usage per period, so that the analog signals for flow and pressure are fed back in real time to minimize energy consumption. In the energy saving monitoring method for a vehicle,
measuring the three-phase current of the inverter through the sensor of the measuring unit and transmitting it to the calculating unit (S10);
calculating and normalizing the average value of the measured three-phase current values, and generating a failure detection variable K _N (S20);
determining whether a failure occurs by comparing the failure detection variable K _N with the first threshold value th1 (S30); and
Including; finally identifying the presence or absence of an open failure of the IGBT among the inverters (S40);
The switch mounted on the inverter is an IGBT (Insulated Gate Bipolar Transistor),
The signal used by the master controller is the current signal connected to the IGBT,
It is possible to replace the speed sensor by calculating the operating speed of the motor based on the current signal and the voltage signal,
The control method corresponds to sensorless vector control, and it is possible to minimize heat loss and energy consumption through the introduction of a modulation technique that can reduce the harmonic content through IGBT, which is a power switching device,
It is possible to determine the operating status of the IGBTs in real time,
Energy saving monitoring method for a vehicle, characterized in that it is possible to measure the amount of usage by period and minimizes energy consumption by receiving feedback on idling data in real time. 3. The method of claim 1 or 2,
Energy saving monitoring method, characterized in that it is possible to minimize the loss (loss) due to inverter non-operation by detecting the state of the hardware in real time and automatically notifying it through the app when an abnormality is detected. In the energy saving monitoring device,
a measuring unit for measuring three-phase current;
a calculation unit for calculating and converting the current values measured by the measuring unit to calculate an average value;
a failure detection unit for detecting whether there is an IGBT open failure using the calculation result of the calculation unit; and
When the failure detection unit detects an IGBT open failure, it includes a failure identification unit for identifying which IGBT is a failure,
a monitor capable of checking the operating status of the IGBTs in real time;
Energy saving monitoring device, characterized in that it can minimize energy consumption by further comprising a real-time sensing unit capable of estimating the energy usage in real time through the monitor. 5. The method of claim 4,
The IGBT receives from the IGBT driver a collector voltage value applied to the collector of the IGBT controlled by receiving the PWM signal, a collector current value flowing through the collector of the IGBT, and an elapsed time value that is a time elapsed from the time when the PWM signal is inputted from the IGBT driver. Energy saving monitoring device, characterized in that receiving. measuring the three-phase current of the inverter through the sensor of the measuring unit and transmitting it to the calculating unit (S10);
calculating and normalizing the average value of the measured three-phase current values, and generating a failure detection variable K _N (S20);
determining whether a failure occurs by comparing the failure detection variable K _N with the first threshold value th1 (S30); and
Including; finally identifying the presence or absence of an open failure of the IGBT among the inverters (S40);
In the energy saving monitoring method,
1) Monitoring the operating status of each IGBT in facilities 1 and 2 in real time,
2) It is possible to determine the failure status of each IGBT,
3) It is possible to observe the current cost of electricity for the entire month,
4) An energy saving monitoring method, characterized in that it is possible to monitor weekly, daily, monthly, and annual power consumption.

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