Grid-connected locking control system for multiple diesel generators

Abstract

The utility model relates to the technical field of power distribution networks, in particular to a grid-connected locking control system for multiple diesel generators, which comprises three 10kV diesel generators, a section of 10kV bus, a set of synchronizing device and a protection device. The output end of each diesel generator is electrically connected to the 10kV bus through a corresponding generator circuit breaker, the 10kV bus is electrically connected to a factory load end through a main power supply circuit breaker, and the synchronizing device internally comprises a voltage sampling circuit connected with a bus side and a generator side, a phase comparison circuit connected with the output end of the voltage sampling circuit, and a power supply circuit connected with the output end of the phase comparison circuit. The blocking signal output circuit is connected with the output end of the phase comparison circuit; and an output node of the blocking signal output circuit is connected in series into a closing control loop of each generator circuit breaker. According to the utility model, the locking system is designed to ensure the electricity utilization safety: the synchronizing device is used for detecting the power supply voltage and additionally arranging the locking switch contact, so that the diesel generator is synchronized and connected to the grid, electricity utilization faults can be prevented, and the electricity utilization safety is ensured.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of distribution network, concretely relates to a kind of multiple diesel generator grid-connected lockout control system. BACKGROUND

[0002] New cement plant needs to start power supply on one hand, also needs security power supply on the other hand, remote area industrial development will face the problem of weak power infrastructure, especially in some emerging industrial countries, it is impossible to provide reliable start power supply and security power supply for newly-built factory and mine, so that the distribution network system cannot be safely and stably operated. UTILITY MODEL CONTENTS

[0003] For the above problems, a multiple diesel generator grid-connected lockout control system is provided, which solves the problem of insufficient power supply in backward areas by this method, provides reliable start power supply and security power supply for newly-built factory and mine, and achieves the purpose of safe and stable operation of distribution network system.

[0004] To solve the problems of the prior art, the utility model provides a kind of multiple diesel generator grid-connected lockout control system, including three 10kV diesel generators, a section 10kV bus, a set of synchronizing device and protection device;Each diesel generator output end is electrically connected to the 10kV bus by corresponding generator circuit breaker, and the 10kV bus is electrically connected to factory load end by main power supply circuit breaker;The synchronizing device is electrically connected with voltage transformer, each generator circuit breaker and main power supply circuit breaker respectively;The inside of the synchronizing device includes: the voltage sampling circuit connected with bus side and generator side, the phase comparison circuit connected with the output end of voltage sampling circuit, the lock signal output circuit connected with the output end of phase comparison circuit;The output node of lock signal output circuit is connected in series in the closing control loop of each generator circuit breaker.

[0005] Preferably, the voltage sampling circuit includes voltage transformers connected to the bus and each generator outlet respectively, the phase comparison circuit includes a microprocessor for calculating voltage amplitude difference, frequency difference and phase angle difference, and the lock signal output circuit includes a relay array connected with the output end of the microprocessor.

[0006] Preferably, the control coil of the main power supply circuit breaker is connected with the start signal output end of the first grid-connected diesel generator through a first control circuit, and connected with a commercial power detection module through a second control circuit, and the first control circuit and the second control circuit are interlocked.

[0007] Preferably, the lock signal output circuit of the synchronizing device is connected in series through normally closed relay contacts to the closing button control loop of the three generator circuit breakers respectively, the control coil of the normally closed relay contacts is connected with the overproof signal of the phase comparison circuit

[0008] Output terminal connection.

[0009] Preferably, the diesel generator has a rated parameter of 10kV / 1800kW, the voltage transformer has a transformation ratio of 10kV / 100V, and the generator circuit breaker and the main power supply circuit breaker are both provided with electric operating mechanisms.

[0010] The utility model has the beneficial effects that compared with prior art:

[0011] The utility model discloses a locking system, guarantees power safety: through the locking switch contact point of power supply voltage of the synchronization device detection, makes diesel generator through finding synchronization and grid connection, can prevent power failure, guarantees power safety, supports the efficient production of enterprise. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 It is a diesel generator 10kV primary system diagram of a plurality of diesel generator grid connection locking control system.

[0013] Figure 2 It is diesel generator grid connection principle diagram and logic relation one of a plurality of diesel generator grid connection locking control system.

[0014] Figure 3 It is diesel generator grid connection principle diagram and logic relation two of a plurality of diesel generator grid connection locking control system.

[0015] Figure 4 It is diesel generator grid connection principle diagram and logic relation three of a plurality of diesel generator grid connection locking control system.

[0016] In order to further understand the characteristics, technical means and specific purposes and functions reached by the utility model, the utility model will be further described in detail in combination with the drawings and specific embodiments.

[0017] Referring to Figures 1-4 A plurality of diesel generator grid connection locking control system, including three 10kV diesel generators, a 10kV bus, a synchronization device and a protection device,

[0018] The output end of each diesel generator is electrically connected to the 10kV bus through the corresponding generator circuit breaker, and the 10kV bus is electrically connected to the factory load end through the main power supply circuit breaker.

[0019] The synchronization device is electrically connected with the voltage transformer, each generator circuit breaker and the main power supply circuit breaker.

[0020] The synchronization device includes: a voltage sampling circuit connected to the bus side and the generator side, a phase comparison circuit connected to the output terminal of the voltage sampling circuit, and a blocking signal output circuit connected to the output terminal of the phase comparison circuit; the output node of the blocking signal output circuit is connected in series to the closing control circuit of each generator circuit breaker.

[0021] The voltage sampling circuit includes voltage transformers connected to the bus and each generator output line respectively; the phase comparison circuit includes a microprocessor for calculating voltage amplitude difference, frequency difference and phase angle difference; and the blocking signal output circuit includes a relay array connected to the output terminal of the microprocessor.

[0022] The control coil of the main power supply circuit breaker is connected to the start signal output terminal of the first grid-connected diesel generator through the first control circuit, and is connected to the mains power detection module through the second control circuit. The first control circuit and the second control circuit are interlocked.

[0023] The interlocking signal output circuit of the synchronization device is connected in series with three generator circuit breakers via normally closed relay contacts.

[0024] The control coil of the normally closed relay contact is connected to the over-limit signal output terminal of the phase comparison circuit in the closing button control circuit.

[0025] The rated parameters of the diesel generator are 10kV / 1800kW, the transformation ratio of the voltage transformer is 10kV / 100V, and both the generator circuit breaker and the main power supply circuit breaker adopt electric operating mechanisms.

[0026] Example 1:

[0027] Reference Figure 1 This system is equipped with three 10kV 1800kW diesel generators, a 10kV busbar, and a set of synchronizing and protection devices.

[0028] Example 2:

[0029] Reference Figures 2-4 :

[0030] In the absence of mains power, starting any one diesel generator and its circuit breaker will activate the CB4 circuit breaker to supply power to the factory. At the same time, the synchronizing device will detect the voltage and lock the circuit breakers of the other two diesel generators. They cannot be closed arbitrarily. Only after the synchronizing device detects the synchronization can the two diesel generators that have not been started be started, closed, and connected to the grid.

[0031] In the case of having commercial power, the second road security power supply is provided for the first and second level load of the factory at any time, the CB4 is in the always closed state, and the synchronizing device detects the voltage of 5YH, that is, the breaker of the three diesel generators is locked, and is not allowed to be closed at will, and only after the synchronizing device detects the synchronization, the diesel generator which is not started can be started and connected to the grid, so as to avoid the power accident caused by non-synchronization closing.

[0032] The above embodiments only express one or several embodiments of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the present application. It should be pointed out that for ordinary skilled persons in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which all belong to the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A multiple diesel generator grid tie latching control system, characterized by, The application relates to a 10kV diesel generator set, which comprises three 10kV diesel generators, a 10kV bus, a synchronization device and a protection device. The output ends of the diesel generators are electrically connected to the 10kV bus through corresponding generator circuit breakers, and the 10kV bus is electrically connected to a factory load end through a main power supply circuit breaker. The synchronization device is electrically connected to a voltage transformer, the generator circuit breakers and the main power supply circuit breaker. The synchronization device comprises voltage sampling circuits connected to the bus side and the generator side, a phase comparison circuit connected to the output ends of the voltage sampling circuits, and a blocking signal output circuit connected to the output end of the phase comparison circuit; and the output node of the blocking signal output circuit is connected in series to the closing control loop of each generator circuit breaker.

2. A multi-diesel-generator grid-connection latching control system according to claim 1, characterized in that, The voltage sampling circuit comprises voltage transformers connected to the bus and the generator outgoing lines respectively, the phase comparison circuit comprises a microprocessor for calculating the voltage amplitude difference, the frequency difference and the phase angle difference, and the blocking signal output circuit comprises a relay array connected to the output end of the microprocessor.

3. A multi-diesel-generator grid-locked control system according to claim 1, wherein, The control coil of the main power supply circuit breaker is connected to the starting signal output end of the first grid-connected diesel generator through a first control loop and connected to a commercial power supply detection module through a second control loop, and the first control loop and the second control loop are interlocked.

4. A multi-diesel-generator grid- tie latching control system in accordance with claim 1, wherein, The blocking signal output circuit of the synchronization device is connected in series to the closing button control loop of the three generator circuit breakers through normally closed relay contacts, and the control coil of the normally closed relay contacts is connected to the over-limit signal output end of the phase comparison circuit.

5. A multi-diesel-generator grid-locked control system according to any one of claims 1-4, characterized in that, The rated parameters of the diesel generators are 10kV / 1800kW, the transformation ratio of the voltage transformers is 10kV / 100V, and the generator circuit breakers and the main power supply circuit breaker are both electrically operated.

Images