Starting system of motor

Abstract

The utility model relates to the field of motor control, in particular to a motor starting system which comprises at least two motors and a soft starter STR, the power supply end of each motor is connected with a frequency conversion control module, the frequency conversion control module can output starting voltage to start the motor, the soft starter STR is connected to the power supply end of each motor, and the frequency conversion control module can output starting voltage to start the motor. The soft starter STR can carry out soft start on the motor. The motor starting system has the effect of improving the redundancy capability of the motor starting system of the fermentation tank in a pharmaceutical enterprise.

Description

Technical Field

[0001] The present application relates to the field of motor control, and in particular to a motor starting system. Background Art

[0002] At present, a large number of motors in industry require variable frequency control, such as the motors of fermentation tanks in pharmaceutical companies. The motors of these fermentation tanks are all secondary loads, and generally each fermentation tank motor often uses an independent frequency converter VF for starting and control; however, once the frequency converter VF fails, the maintenance or replacement time of the frequency converter VF is relatively long, and the downtime of the fermentation tank motor will cause the entire fermentation tank solution to be scrapped, which will cause great economic losses.

[0003] Therefore, how to improve the redundancy capability of the motor starting system of the fermentation tank in pharmaceutical companies is an urgent problem to be solved. Utility Model Content

[0004] In order to improve the redundancy capability of the motor M starting system of the fermentation tank in the pharmaceutical enterprise, the present application provides a motor starting system.

[0005] The present application provides a motor starting system that adopts the following technical solution:

[0006] A starting system for a motor, comprising:

[0007] At least two motors M and one soft starter STR;

[0008] The power supply end of each motor M is connected to a frequency conversion control module, and the frequency conversion control module can output a starting voltage to start the motor M;

[0009] The soft starter STR is connected to the power supply end of each motor M, and the soft starter STR can perform soft start on the motor M.

[0010] By adopting the above technical solution, each motor M can be started by the frequency conversion control module or the soft starter STR. When any frequency converter VF fails, the motor M corresponding to the frequency converter VF can be started by the soft starter STR, which prevents the motor M of the fermentation tank from being shut down for a long time, thereby reducing economic losses.

[0011] Optionally, the frequency conversion control module includes a frequency converter VF and an output inductor L, the input end of the frequency converter VF is connected to three live wires, the output end of the frequency converter VF is connected to the output inductor L, and the output inductor L is connected to the power supply end of the motor M.

[0012] By adopting the above technical solution, when the inverter VF is started, instantaneous high voltage will be generated inside it. The output inductor L can extend the effective transmission distance of the inverter VF, and can suppress the instantaneous high voltage generated when the IGBT module of the inverter VF is switched, thereby protecting the motor M.

[0013] Optionally, the motor starting system further includes at least two groups of switching modules, each of which corresponds to the motor M one by one, and the switching module can switch the power supply end of the motor M to connect to the frequency conversion control module or to the soft starter STR.

[0014] By adopting the above technical solution, the switching module can switch the motor M to be started by the frequency conversion control module or to be started by the soft starter STR, reducing the probability that the soft starter STR and the frequency conversion control module simultaneously power and start a motor M, thereby improving the safety of the motor M.

[0015] Optionally, the switching module is a double-ended conversion switch AN, the output end of the soft starter STR is connected to the first power supply end A of the double-ended conversion switch AN, the output end of the output inductor L is connected to the second power supply end B of the double-ended conversion switch AN, and the switching end of the double-ended conversion switch AN is connected to the power supply end of the motor M.

[0016] Optionally, a safety protection module is connected between the input end of the frequency conversion control module and the three live wires, and the safety protection module includes an isolating switch QS, a circuit breaker QF, a first contactor KM1, a current transformer TA and a fuse QFS which are sequentially connected in series.

[0017] By adopting the above technical solution, when leakage and short circuit occur in the power supply circuit of the motor M provided by the motor M variable frequency control module, the safety protection module can cut off the power supply circuit to the motor M, thereby reducing damage to the inverter VF and the motor M.

[0018] Optionally, the safety protection module is connected between the input end of the soft starter STR and the power supply line.

[0019] Optionally, the rated power of the soft starter STR is greater than the power of the frequency converter VF.

[0020] By adopting the above technical solution, the power of the soft starter STR is greater than the power of the frequency converter VF, which means that when a frequency conversion control module fails, the soft starter STR can at least start one motor M stably.

[0021] In summary, the present application includes at least one of the following beneficial technical effects:

[0022] 1. Each motor M can be started through the frequency conversion control module or the soft starter STR. When any frequency converter VF fails, the motor M corresponding to the frequency converter VF can be started through the soft starter STR, which prevents the motor M of the fermentation tank from being shut down for a long time, thus reducing economic losses;

[0023] 2. The switching module can switch the motor M to be started by the frequency conversion control module or switched to be started by the soft starter STR, reducing the probability that the soft starter STR and the frequency conversion control module simultaneously power on a motor M, thereby improving the safety of the motor M;

[0024] 3. When leakage and short circuit occur in the power supply circuit of the motor M provided by the motor M variable frequency control module, the safety protection module can cut off the power supply circuit to the motor M, thereby reducing damage to the inverter VF and the motor M. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the principle of a motor starting system using two motors M as an example in an embodiment of the present application. DETAILED DESCRIPTION

[0026] The following is combined with Figure 1 This application is described in further detail.

[0027] In industry, the frequency converter is usually used to start and power the motor alone. However, once the frequency converter fails, it takes a long time to repair or replace the frequency converter, and the long downtime of the motor will cause great economic losses.

[0028] The present application embodiment discloses a motor starting system, referring to Figure 1 The system includes at least two motors M, a soft starter STR, at least two frequency conversion control modules and at least two switching modules. In the embodiment of the present application, only one achievable scenario is used as an example. In the embodiment of the present application, the motors M are all motors of the fermentation tank, but this does not limit the scenarios in which the system can be applied. In fact, the motor starting system of the present application can also be applied to motors of other devices or even a single motor.

[0029] Specifically, the frequency conversion control module corresponds to the motor M one by one, and the power supply end of each motor M is connected to a corresponding frequency conversion control module, and the frequency conversion control module can output a starting voltage to start the corresponding motor M. The switching module corresponds to the motor M one by one, and the switching module can switch the power supply end of the motor M to connect to the frequency conversion control module or to the soft starter STR.

[0030] In the scheme of the embodiment of the present application, each motor M can be started by a frequency conversion control module or a soft starter STR. When any frequency converter VF fails, the motor M corresponding to the frequency converter VF can be switched to the soft starter STR for starting through the switching module. This prevents the motor M of the fermentation tank from being shut down for a long time, thereby reducing economic losses.

[0031] Furthermore, the soft starter STR is connected in parallel with a power supply module, which includes a second contactor KM2 and a thermal relay FR which are connected in series in sequence; in practice, the soft starter STR is only used to start the corresponding motor M, and then the power supply module is switched to supply power to the corresponding motor M.

[0032] Specifically, refer to Figure 1 The frequency conversion control module includes a frequency converter VF and an output inductor L. The input end of the frequency converter VF is connected to three live wires, the output end of the frequency converter VF is connected to the output inductor L, and the output inductor L is connected to the power supply end of the motor M.

[0033] Specifically, refer to Figure 1 , the switching module is a double-ended conversion switch AN. The output end of the soft starter STR is connected to the first power supply end A of the double-ended conversion switch AN; the input end of the frequency converter VF is connected to the power supply line, the input end of the output inductor L is connected to the output end of the frequency converter VF, and the output end of the output inductor L is connected to the second power supply end B of the double-ended conversion switch AN; the switching end of the double-ended conversion switch AN is connected to the power supply end of the motor M. The double-ended switching switch can be a double-ended switching knife switch or other types of double-ended switching switches. The type of the switching switch in the embodiment of the present application is not specifically limited.

[0034] Further, refer to Figure 1 , the frequency conversion control module and the soft starter STR are connected to the power supply line with a safety protection module. Specifically, the safety protection module includes an isolating switch QS, a circuit breaker QF, a first contactor KM1, a current transformer TA and a fuse QFS connected in series in sequence; that is, the input end of the frequency converter VF and the power supply line are connected in series with an isolating switch QS, a circuit breaker QF, a first contactor KM1, a current transformer TA and a fuse QFS. The input end of the soft starter STR and the power supply line are connected in series with an isolating switch QS, a circuit breaker QF, a first contactor KM1, a current transformer TA and a fuse QFS. Furthermore, a digital energy meter W is connected in series between each isolating switch QS and the power supply line to detect the voltage, current and consumed energy of the circuit.

[0035] When leakage and short circuit occur in the power supply circuit of the motor M provided by the motor M variable frequency control module, the safety protection module can cut off the power supply circuit to the motor M, thereby reducing damage to the inverter VF and the motor M.

[0036] Furthermore, since at least two motors M are included in the solution of the embodiment of the present application, in practical applications, the motor M starting system of the present application can also control more motors M, and the specific number is not specifically limited in the embodiment of the present application. In the embodiment of the present application, four motors M are used as an example. It should be noted that each motor M corresponds to a frequency conversion control module, and each frequency conversion control module corresponds to a safety protection module. The output inductor L in each frequency conversion control module is connected to the power supply end of the corresponding motor M and the output end of the soft starter STR through a switching module.

[0037] Although the probability of both inverters VF corresponding to two motors M failing in the same time period is small, in order to enable both motors M corresponding to the two inverters VF to start in a relatively short time when this happens, it is required that the inverter VF in the motor starting system of the present application can simultaneously start at least two motors M. Therefore, in the embodiment of the present application, the rated power of the soft starter STR is greater than the rated power of the inverter VF.

[0038] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A motor starting system, characterized in that: include At least two motors M and one soft starter STR; The power supply end of each motor M is connected to a frequency conversion control module, and the frequency conversion control module can output a starting voltage to start the motor M; The soft starter STR is connected to the power supply end of each motor M, and the soft starter STR can perform soft start on the motor M.

2. A motor starting system according to claim 1, characterized in that: The frequency conversion control module includes a frequency converter VF and an output inductor L, the input end of the frequency converter VF is connected to three live wires, the output end of the frequency converter VF is connected to the output inductor L, and the output inductor L is connected to the power supply end of the motor M.

3. A motor starting system according to claim 2, characterized in that: It also includes at least two groups of switching modules, each of which corresponds to the motor M. The switching module can switch the power supply end of the motor M to connect to the frequency conversion control module or to the soft starter STR.

4. A motor starting system according to claim 3, characterized in that: The switching module is a double-ended conversion switch AN, the output end of the soft starter STR is connected to the first power supply end A of the double-ended conversion switch AN, the output end of the output inductor L is connected to the second power supply end B of the double-ended conversion switch AN, and the switching end of the double-ended conversion switch AN is connected to the power supply end of the motor M.

5. A motor starting system according to any one of claims 1 to 4, characterized in that: A safety protection module is connected between the input end of the frequency conversion control module and the three live wires. The safety protection module includes an isolating switch QS, a circuit breaker QF, a first contactor KM1, a current transformer TA and a fuse QFS which are sequentially connected in series.

6. A motor starting system according to claim 5, characterized in that: The safety protection module is connected between the input end of the soft starter STR and the power supply line.

7. A motor starting system according to any one of claims 2 to 4, characterized in that: The rated power of the soft starter STR is greater than the power of the frequency converter VF.

Images